S P E C T R A - Carnegie Institution for Science...S P E C T R A Summer 2000 THE NEWSLETTER OF THE CARNEGIE INSTITUTION Department of Plant Biology Department of Terrestrial Magnetism

S P E C T R A SummerSummerSummerSummerSummer20002000200020002000

T H E N E W S L E T T E R O F T H E C A R N E G I E I N S T I T U T I O NT H E N E W S L E T T E R O F T H E C A R N E G I E I N S T I T U T I O NT H E N E W S L E T T E R O F T H E C A R N E G I E I N S T I T U T I O NT H E N E W S L E T T E R O F T H E C A R N E G I E I N S T I T U T I O NT H E N E W S L E T T E R O F T H E C A R N E G I E I N S T I T U T I O N

Department ofPlant Biology

Department ofTerrestrial Magnetism

Department ofEmbryology

TheObservatories

GeophysicalLaboratory

CASE/First Light

Extending the Frontiers of Science

S P E C T R A

Above is the Carnegie Observatories’ official first-day envelope and cancellation for the Edwin P. Hubble commemorative stamps.The envelope features the young Hubble at the 100-inch Mount Wilson telescope.

INSIDE:New Board Members ................................................. 2Signatures of Life—Carnegie Evening 2000 ........... 3Honoring Hubble .......................................................... 4One Little Cell with Lots to Tell ................................ 5Magellan I Mirror Is In! ................................................ 8

Fruit Fly Genome Sequenced .................................... 9Algae at the Desert Lab? ............................................. 9Watery Mars ................................................................10New Reading ................................................................10Web Watch...................................................................16

2�❖ SUMMER 2000 ❖ SPECTRA: THE NEWSLETTER OF THE CARNEGIE INSTITUTION ❖

LETTER FROM THE CHAIRMAN

C A R N E G I EI N S T I T U T I O NO F W A S H I N G T O N

1530 P Street, N.W.Washington, D.C. 20005-1910

(202) 387-6400Web site: http://www.ciw.edu

Maxine F. Singer, PresidentAugustus Oemler, Jr., Director,

The ObservatoriesWesley T. Huntress, Jr., Director,

Geophysical LaboratorySean C. Solomon, Director,

Department of TerrestrialMagnetism

Christopher Somerville, Director,Department of Plant Biology

Allan C. Spradling, Director,Department of Embryology

John J. Lively, Director, Adminis-tration and Finance

Susanne Garvey, Director, ExternalAffairs

Tina McDowell, EditorEllen Carpenter, Assistant Editor

and Designer

Carnegie has been inthe business of sciencefor almost one hundredyears. When we reflecton our history, we haveto ask, “What have weaccomplished?”

For almost a centurywe have provided theworld with countlessdiscoveries andinnovations—from

Barbara McClintock’s genetic breakthroughsto Hubble’s discovery of our place in theuniverse. These examples and others haveprofoundly influenced everyday lives.Carnegie’s recent achievements in areassuch as genetics, planetary and earthscience, and astronomy illustrate how ourinstitution continues to make society better.

In March, the Drosophila genome wasofficially sequenced. Embryology’s director,Allan Spradling, and former Staff MemberGerald Rubin were pivotal in initiating thiswork, which began almost a decade ago.The project has yielded 177 geneticcounterparts for genes that are linked to

human diseases. This means that asscientists learn more about gene function inthe fruit fly, they will learn more aboutcuring illnesses in people.

Genetic research on the model organismChlamydomonas reinhardtii at Plant Biologyis a similar case. Art Grossman’s career-long work with this single-celled alga isrevealing important insights into how plantsacclimate to different environmentalconditions. The payoff? Researchers will beable to develop food crops that can grow ina broader range of climates and keep upwith the needs of the world’s growingpopulation.

Scientists from three Carnegie depart-ments—Terrestrial Magnetism, PlantBiology, and the Geophysical Lab—continueto help us understand more about the Earth.DTM’s director, Sean Solomon, for instance,unravels the mysteries of our sister planets,providing insights into Earth’s evolution.Chris Field and Joe Berry at Plant Biologyinvestigate the human role in environmentalchange on our own planet. At GL, MarilynFogel studies biological and geologicalprocesses in the Earth’s past and present

environments. Ultimately all of this workwill help to improve the planet’s long-termhabitability.

Our fundamental understanding ofmatter, energy, and the principles on whichthe universe operates is enhanced withresearch at the Observatories. WendyFreedman’s role in determining theexpansion rate of the universe, and LuisHo’s investigations into black holes areexamples. Practical results aside, whatcould be more important?

None of the science we do today wasenvisioned a hundred years ago. Nor can weimagine what the next hundred years will belike. But we do know that Carnegie’sachievements today and tomorrow willcontinue to provide the foundations onwhich future generations will build toimprove the world that they inherit from us.

Tom Urban

Tom Urban

NEW MEMBERS JOIN THE BOARD

Former Embryology Staff Member Steven McKnight waselected to the board of trustees at the May meeting inWashington, D.C. McKnight joins Daniel Belin as thenewest Carnegie board members. Daniel Belin, who waselected to the board in December, is a founding partner ofthe Los Angeles law firm Belin Rawlings & Badal. He is atrustee of the Ahmanson Foundation, the Samuel H. KressFoundation, and serves on a variety of other boards andvisiting committees.

Steven McKnight has been affiliated with Carnegie for manyyears. He came to the Department of Embryology as a staffassociate in 1979 and left as a Staff Member in 1992 to cofoundTularik, Inc. At present, he is the chairman of the Department ofBiochemistry at UT Southwestern Medical Center. He holds theSam G. Winstead and F. Andrew Bell Distinguished Chair, andthe Distinguished Chair in Basic Biomedical Research.

SUMMER 2000 ❖ SPECTRA: THE NEWSLETTER OF THE CARNEGIE INSTITUTION ❖ �3

Marilyn Fogel, a StaffMember at the Geophysi-

cal Lab, was this year’s CarnegieEvening speaker. Her visuallyappealing, fast-moving lecture wassprinkled with stories about what itis really like to collect data in thefield. Fogel discussed her workdetecting “signatures of life” onEarth and explained how hermethods can be applied to thesearch for life on extraterrestrialbodies.

Fogel’s research blends the fieldsof biology, chemistry, and geology.She described how she uses isotopesof carbon, oxygen, and nitrogen tounderstand the biological andgeological processes in Earth’s pastand present environments. Shepresented several examples toillustrate how she applies hertechniques to trace phenomena as

varied as the nature ofthe first microorgan-isms on our planet, and the landscapeand climate of ancient Australia. Fogelalso talked about how she anticipatesanalyzing samples, such as those fromfuture missions to Mars, to hunt forevidence of life elsewhere.

Signatures of Life—Carnegie Evening 2000

May 2000, Board of Trustees: First row, from left: Michael Gellert, Tom Urban(chairman), Maxine Singer (president), Suzanne Nora Johnson, DavidSwensen. Second row: Sandra Faber, Sidney J. Weinberg, Jr., Tom Cori,Burton McMurtry, Philip Abelson, Gary Ernst. Third row: John Diebold, BruceFerguson, David Greenewalt (secretary), Robert Goelet, Jaylee Mead, JohnCrawford, Christopher Stone, James Ebert, William Rutter, Frank Press. Notpictured: Euan Baird, Daniel Belin, William Coleman, Jr., William Golden,William Hearst III, Kazuo Inamori, Gerald Laubach, Steven McKnight, JohnMacomber, Richard Meserve, and William I. M. Turner, Jr. (vice chairman).

Left: Trustee Tom Cori and Marilyn Fogelenjoy a moment after the lecture.

Below: After a day ofboard business,trustees RichardMeserve (left), RobertGoelet (middle), andTom Cori (right) get achance to relax.

Right: More than 350 guestsfilled the administration

building for CarnegieEvening on May 4.

Steven McKnight

Daniel Belin


Carnegie astrono-mer Edwin P.

Hubble revolutionizedour concept of the uni-verse, compelledEinstein to revise hisTheory of Relativity,and is the man forwhom the HubbleSpace Telescope isnamed. The U. S. PostalService honored theman and the telescopeon April 10 by issuingfive commemorativestamps. Two first-day-of-issue cer-emonies were held: one on theObservatories’ campus in Pasa-dena, California, where Hubblewas a staff member from 1919 un-til his death in 1953, and theother at the NASA GoddardSpace Flight Center in Greenbelt,Maryland.

Robert Mysel, postmaster ofPasadena, presided over theCalifornia ceremony, which wasattended by more than 200guests, six TV stations, tworadio stations, and severalnewspaper reporters. GusOemler, director of the Obser-

vatories, welcomed the audience.Speaking about about Hubble’slife and accomplishments, hesaid, “Edwin Hubble is recog-nized as the greatest astronomersince Galileo and is certainly themost influential astronomer thatthis nation has produced.”Oemler, Allan Sandage, andSteven Hawley, an astronomerand astronaut from the NASAJohnson Space Flight Center,then unveiled the stamps.

Allan Sandage took the po-dium next. He referred to theObservatories as “the best-keptsecret in Pasadena,” and said that

the fantastic discover-ies on Mount Wilson“made this city theworld center ofastronomy for mostof the past century.”Pointing to theObservatories’ build-ings, he continued,“It was in thoseoffices, constructed in1912 in the middle offarmland, citrusgroves, and vine-yards that the foun-

dations of the grand picture ofcosmology originated.”

The parallel celebration, atNASA Goddard Space FlightCenter, was also cohosted bythe U.S. Postal Service.Carnegie president MaxineSinger, NASA director DanielGoldin, and Space TelescopeScience Institute director SteveBeckwith unveiled the stamps.In a talk later that day atGoddard, Carnegie’s AlanDressler noted that “the HST iscontinuing Edwin Hubble’sown work of measuring theexpansion rate of the universe.”

Honoring Hubble

It’s “thumbs up” for the formal unveiling of the Hubblestamps in Pasadena. Astronaut Steven Hawley (left),Observatories’ director Gus Oemler, and Edwin Hubble’ssuccessor Allan Sandage (right) participate in theceremony. Photo: Courtesy Michael Jones, U.S. PostalService.

The East Coast event for the first day of issue was held atNASA Goddard Space Flight Center in Maryland. From leftto right: NASA administrator Daniel Goldin, Carnegiepresident Maxine Singer, and Postmaster General WilliamHenderson.


(a fixed carbon source that can serveas its energy supply); at 10 microns itis large enough to see microscopically;it reproduces quickly; it can be storedfor long periods; and it is a haploidorganism with each cell containing asingle copy of the nuclear genome.This last characteristic makes it goodfor generating mutants and forperforming classical genetic analyses.

Chlamy is a single-celled organismthat can be maintained in cultureunder highly defined conditions. It istherefore better for certain types ofstudies than vascular plants becausethe analyses are not complicated bymultiple tissue types, such as roots andshoots, that are exposed to differentenvironments. Furthermore, Chlamycan grow by feeding directly on afixed carbon source without light,whereas vascular plants need photo-synthetic carbon fixation to survive.Because of this feature, it is mucheasier to create viable mutants thataffect photosynthetic processes in thealga.

Important parts

There are several critical, function-ally distinct compartments in plant cells.Among them is the nucleus, which is thecontrol center of the cell; the mitochon-drion, where energy is extracted fromfood in a process called respiration; andthe chloroplast, where the plant absorbsand converts the energy from the sunto glucose for nourishment. These com-partments all have their own genomes.Genes that have been isolated and char-acterized can be introduced into any ofthese three compartments in Chlamy.As in vascular plants, integration ofgenes into the Chlamy nuclear genomeis random, which means that the intro-duced genes cannot be inserted into aconsistent location on the chromo-somes. However, Chlamy is unique withrespect to vascular plants in that genescan be readily integrated into both themitochondrial and the chloroplast ge-nomes. The integration of DNA into thechloroplast genome, where much of themachinery for photosynthesis is en-coded, is by homologous recombina-

To understand how plantsacclimate to a changingenvironment, Arthur

Grossman studies simple, single-celledalgae—a group of organisms he hasinvestigated throughout his career.Researchers in Grossman’s lab at theDepartment of Plant Biology aretrying to identify the genes andunderstand genetic processes thatallow plants to sense and react to theirdynamic environment. They areparticularly interested in the details ofhow plants respond to differentnutrient levels and light conditions.This research has important implica-tions for agriculture: developing anunderstanding of how plants acclimateto different light and nutrient condi-tions will help researchers engineercrops to prosper in a broader range ofenvironments. It is also helping tobuild a body of knowledge on theevolution of biological processes inplants.

The mustard plant Arabidopsis isone of the model organisms thatresearchers in the Grossman lab haveused, but increasingly the investigatorshave focused on algae. They primarilyexamine the green alga Chlamydomo-nas reinhardtii, and a variety of “blue-green algae,” more properly calledcyanobacteria. Cyanobacteria areactually photosynthetic bacteria thatcontain all of the machinery necessaryfor photosynthesis; much of thismachinery is similar to that of vascularplants.

Why algae?

Although algae are the simplest ofplants, green algae, such as Chlamy-domonas reinhardtii, contain all of thesame pigments in essentially the sameproportions as vascular plants, theirmore complicated cousins. In fact,green algae are thought to be theevolutionary precursors to vascularplants. Chlamy, as this alga is affec-tionately called, is ideal for nutritionaland photosynthetic studies because itis simple and cheap to grow; it can begrown photosynthetically in the light,or in the dark by feeding it on acetate

tion. Researchers can therefore replacean existing gene on the chloroplast ge-nome with one that has been altered ormutated invitro. Thephenotype,or observ-able charac-teristics ofthe strainfor which achloroplastgene hasbeen al-tered, pro-vides impor-tant clues concerning the function ofthat gene in the alga (for example, elimi-nation or modification of any of a num-ber of chloroplast genes alters the abil-ity of the organism to perform photo-synthesis). Chlamy is also ideal for clas-sical genetic crosses; it takes only 10 to14 days to perform a cross and to char-acterize the phenotypes of the progeny.In Arabidopsis the same analysis can takemonths.

Markers help locate genes

Many mutations of Chlamy’snuclear genome have been obtainedby treating the organism with chemi-cals or UV light. This treatmentgenerates small changes in thegenome that are not easy to locate.However, there are now a number ofboth physical and genetic markers onthe Chlamy genome that are enablingresearchers to find and identify themutated gene sequences. The markersare of several types. They can beindividual genes associated with aparticular observable characteristic orphenotype, physical features associ-ated with a DNA sequence, or both.The markers are located at specificlocations on the Chlamy chromo-somes and are powerful landmarks formapping a gene to a unique region ofthe chromosome and for identifyinglesions in genes that cause particularmutant phenotypes.

➤

One Little Cell with Lots to Tell

Arthur Grossman is shownhere in his lab.


Finding out what a genedoes

The process to determine what agene does can be tedious. Sometimesa gene’s function can be inferred fromthe similarity it has to genes in otherorganisms that have already beencharacterized. However, to begin tounderstand the activity encoded by agene and the precise biologicalprocess in which that activity func-tions, it is critical to generate muta-tions and compare mutated organismswith wild-type, or normal, organisms.This analysis may reveal differencesbetween the mutants with respect tomorphology, development, or variousbiochemical processes.

Getting DNA into a single-celled alga

There are three main methods ofintroducing DNA into cyanobacteriaand green algae, and they are all usedin the Grossman lab: glass beadtransformation, electroporation, andthe biolistic procedure. Glass beadtransformation works well for a strainof Chlamy that lacks a cell wall. Thealgal cells are submerged in a solutioncontaining the DNA and finelyground glass beads. The suspension isvigorously mixed with a device calleda vortex for 30 seconds. The glassbeads apparently abrade the cells andgenerate transient gaps in the cellmembrane through which the DNAcan enter. In electroporation, thealgae are submerged in a low-saltsolution containing the DNA. Anelectrical current is discharged thatopens the cytoplasmic membranes ofthe cell, allowing the DNA to perme-ate. This procedure has been usedwith both Chlamy and cyanobacteria.The biolistic procedure involvesbombarding the algae withmicropellets coated with DNA. All ofthese methods can be used both togenerate mutants and to identifygenes that have been altered in themutant strains.

Making mutants

In some organisms, including manycyanobacteria, it is relatively easy togenerate mutants by “knockout”strategies. The generation of knockoutmutations involves the specificreplacement of the original, normalcopy of the gene with a copy that hasbeen altered and no longer performsits normal function. In many cases aspecially engineered drug-resistantcassette, for example one resistant tospectinomycin, can be placed into themiddle of an isolated gene of interest.The gene disrupted by the cassettecan be introduced into wild-typecyanobacterial cells, where it willexchange with the normal copy of thegene. Strains harboring the inter-rupted version of the gene are readilyidentified as being drug resistantbecause they don’t die in the presenceof spectinomycin. Since the normalfunction of the gene has also beeninactivated in these strains, thescientists analyze the mutated organ-ism for features that differ from thoseof wild-type cells.

THE PHOTOSYNTHESIS

ENGINE

Chlamy has served as theclassic model for studies of photo-synthesis, a process primarilyperformed within chloroplasts.Chlorophyll, the pervasive greenpigment in plants, as well as theorange and yellow pigmentedcarotenoids, are located in thisorganelle. Most of the chloro-phylls and carotenoids are associ-ated in structures called light-harvesting complexes. Thesestructures consist of subunits ofproteins, molecules of chlorophyll,and molecules of carotenoids thatare all embedded in a lipid ma-trix. The pigments in these light-harvesting complexes absorb ortrap certain wavelengths of lightand transfer that light, or excita-tion energy, to specialized chloro-phyll molecules in the photosyn-thetic reaction centers; thesereaction centers are the foci forthe primary photochemistry thatdrives photosynthesis. The ener-gized chlorophylls within thesecenters pass high-energy electronsto acceptor molecules. Thisinitiates a series of reduction (thegain of an electron) and oxidation(the loss of an electron) reactionsthat eventually lead to the produc-tion of sugars that fuel metabolicprocesses in plants and, ulti-mately, the animals that eat them.The carotenoids associated withthe light-harvesting complexes arealso extremely important for thedissipation of excitation energywhen the plant is absorbing morethan it can use for photosynthesis.(The absorption of excess lightenergy by plants can lead to theproduction of potentially toxicreactive oxygen species.)

One Litt

These images show what happensduring phosphorus starvation inChlamydomonas. To monitor thelevel of the protein Psr1—aregulator of some of the responsesto phosphorus starvation—theresearchers quantified and localizedPsr1 after the cells were exposed todifferent conditions. The redfluorescence indicates the presenceof DNA and marks the nucleus (left)of phosphorus-starved cells. Thepresence of Psr1 in these samenuclei was determined by an


phycobilisome degradation duringnutrient limitation. It also controlsother cellular processes that arecritical for the survival of cells duringnutrient limitation. The NblS proteinappears to regulate the activity ofNblR and is hypothesized to be themolecule that integrates informationprovided by a variety of environmen-tal signals; it tunes cellular metabolismand growth to the information pro-vided by environmental signals.Interestingly, NblS contains a domainthat binds a pigment called a flavin.The flavin can serve as a redoxmolecule that can both accept anddonate electrons; it can also absorbblue and UV-A light. During allnutrient stress conditions the redoxstate of the cell is elevated and NblSmay be able to quantify cellular redoxthrough the bound flavin. The redoxstate of the flavin may then modulatethe activity of a group of transcriptionfactors—genes that control the expres-sion of other genes—that are involvedin regulating metabolic processes.NblS also appears to control a numberof genes whose activity is controlledby the light environment. Many of thegenes encoding proteins of thephotosynthetic apparatus are con-trolled by blue/UV-A light (which isoften a signal for high light in theenvironment). The blue/UV-A lightsignal appears to be communicated tothe transcriptional apparatus of thecell through NblS. Therefore, NblSfunctions as a global cell regulator thatuses the redox state and the lightenvironment as an indicator of thecell’s potential for growth and thentunes photosynthesis and probablyother metabolic processes accordingly.

These studies in Grossman’s labraise a lot of questions about how avariety of environmental cues arefused into a single cue that is repre-sented by redox and, possibly, thelevel of reactive oxygen radicals in thecell. This work also suggests thatredox components involved inelectron transfer reactions haveevolved into both regulatory mol-ecules and photoreceptors.

Locating the starvation-response genes

To understand the details of whathappens during nutrient starvation,the scientists first mutated normal cellswith a chemical mutagen. This createdrandom base changes in the genomicDNA, generating populations ofmutant cells. The mutants werescreened for those that specificallylooked blue-green following nutrientlimitation, indicating they were unableto degrade their light-harvestingcomplex. The single base changesoften caused by the chemical mu-tagens are too small to find easily, sothe scientists identified the mutatedgenes by a process called complemen-tation. In this process, the researchersplaced a library of pieces of genomicDNA from normal cells into a plasmidvector (a carrier molecule containing agenetic marker) and then introducedthe material into the mutant strains.The plasmid, plus normalcyanobacterial DNA, recombines intospecific locations in the genomicDNA. The researchers visuallyidentified those strains that exhibitednormal bleaching during nutrientlimitation, and then isolated andcharacterized the genes of interest bylocating the plasmid marker in thegenome.

How the genes function

In this manner, the researchersidentified four genes involved inmodifying the photosynthetic appara-tus during nutrient stress. Two of thegenes isolated encode proteins thatare directly involved in the destruc-tion of phycobilisomes—the majorlight-harvesting complex ofcyanobacteria. The remaining twogenes encode regulatory proteins thathave been designated NblR(nonbleaching regulator) and NblS(for nonbleaching sensor). NblR is aDNA-binding protein and is criticalfor activating specific genes thatencode proteins that function in

Responding to starvation

Grossman wants to understandwhat genes and processes are active inphotosynthetic organisms that allowthem to sense nutrient levels andacclimate to nutrient-deficient condi-tions. When cyanobacteria are starvedfor a specific nutrient, the organismsynthesizes systems to help scavengefor the limiting nutrient more effi-ciently. The organism also undergoesa more general response: cells stopgrowing, the light-harvesting complexis degraded, and photosyntheticelectron transport shuts down. It isessential that the cell eliminate mostphotosynthetic electron transportduring nutrient limitation. If thesystem were not shut down, it wouldproduce reactive oxygen species,which could burn up the cell. Theredox state of the cell would alsoincrease, which could adversely affectmetabolic control. With the degrada-tion of the light-harvesting complexduring nutrient limitation, the cellslook yellow or bleached instead ofblue-green.

immunological stain and is indicatedby green fluorescence (middle). Theyellow represents an overlap ofPsr1 fluorescence (green) withfluorescence from nuclei (red)(right). These results show that Psr1is a protein that specifically localizesto the nucleus. When similarexperiments were performed withcells that were not starved forphosphorus, very little Psr1 wasobserved. The level of the Psr1protein goes up at least 10 foldduring phosphorus deprivation.

tle Cell...

continued on page 11


April 30, 2000

Dear colleagues:

I’m pleased to announce that theMagellan I 6.5-meter primary mirrorhas been successfully installed in themirror cell. The procedure tookplace on Wednesday andThursday of last week in theMagellan coatings facility (the“auxiliary” building).

The installation teamconsisted of Magellan Projectand LCO staff assisted bySteve Warner from the Uni-versity of Arizona. Nineteenpeople were involved, includ-ing the safety officer and thephotographer. Before starting,a detailed procedure wasreviewed and discussed aheadof time with the team.

The lift started at 7:30Thursday morning. First,Warner dressed out the onedefect in the back surfacefound earlier by Frank Perez. Themirror was picked off the shippingframe with the vacuum lift fixture.Once the mirror was in the air therewas no stopping until it was in thecell.

An inspection with the mirrorraised revealed no additional defectsin areas that were inaccessible whenthe mirror was in the shippingcontainer. Once the mirror was

raised, the shipping frame was rolledout of the way, and the telescopecell was positioned below the mirror.The process of lowering the mirror

into the cell was tedious butwas accomplished withoutmajor drama, as the Chileanssay. The bolts that hold themirror in the telescope wereinstalled, and the mirror wasset down on the staticsupports. The lift fixture wasdetached at 4:00 p.m.,completing the installation.

On Friday, the primarymirror and cell were driveninto the enclosure and in-

stalled in the telescopealong with the tertiarymirror assembly. We hadsome minor difficulty

attaching the tertiary supportbase but in the end weprevailed. The mirror is nowsafely installed in the tele-scope and is protected by themirror covers.

The primary mirror will betested initially without itsaluminum coating. Thereflection off the bare glasswill be enough to see brightobjects. When the aluminiz-ing chamber is ready later this

IT’S IN!

summer the mirror will be taken outof the telescope and coated in itscell. At that time we will install theprimary mirror thermal-control

system. The crew is currently

engaged in installing andaligning the primary mirrorsupports. This work will takemuch of May to complete.During this time the second-ary mirror will be reinstalledin the telescope and thetelescope optical supportstructure will be balanced.The secondary and tertiarymirrors were aluminizedpreviously. The initial align-ment of the optics will be

accomplished with alignmenttelescopes and fixtures speciallydesigned for this purpose.

There is still a tremendousamount of work left to be done tomake the telescope truly ready forobserving, but this last week markeda major milestone in that process.

On behalf of the Magellan team,

Matt Johns, Magellan Project Manager

The mirror is suspended over the mirror cellas Matt Johns (left) and Frank Perez(on the ladder) look on.

Magellan Project scientist Steve Shectman (left)and Las Campanas director Miguel Roth(bottom) assist as Frank Perez takes the finalbits of coating off the surface.

Steve Warner (left) from the University ofArizona Steward Mirror Lab and Carnegie’sFrank Perez take off the protective coating thathas shielded the glass since it left Arizona.


The completed sequenceof the Drosophila ge-

nome was published in theMarch 24, 2000, issue ofScience. The fruit fly has about13,600 genes, 99% of whichnow have been mapped. Twoof the players on the team ofscientists and engineers whodecoded the genome areEmbryology’s director (andHoward Hughes MedicalInstitute [HHMI] investigator)Allan Spradling and formerEmbryology Staff MemberGerald Rubin. Rubin, now atthe University of California-Berkeley, is vice president ofHHMI and leader of thegenome project. Nine yearsago, the pair launched thesequencing as one componentof the Drosophila genome effort.But their history as collabora-tors goes back even further.

In 1981, Spradling andRubin (then both Staff Mem-bers at the Department ofEmbryology) made agroundbreaking discovery—anew method of gene transfer.They showed that an externalgene could be successfullyinserted and expressed in thefruit fly’s germ cells—cells thatgive rise to gametes. Spradlingand Rubin’s experiments usedtransposable elements: thephenomena discovered byCarnegie geneticist BarbaraMcClintock, in which genesseem to jump within or be-tween chromosomes. Theyused this feature to “ferry”sequences of DNA called P-elements into embryos. Thismethod allowed scientists to

study genes of complexmulticellular organismsdirectly for the first time.Spradling and Rubin’s P-element experiments alsospawned the creation oftransgenic flies and theunprecedented manipulationof the Drosophila genome,which opened the door tothe development of a new,powerful gene-manipulationtechnology.

Now that the structures ofthe genes have beenmapped, the genome projectwill concentrate on deter-mining how the genesfunction. Indispensable toolsin this task are fly strainsbearing a mutation in justone of the genes. In 1988,Spradling’s group developeda way to generate particu-larly useful mutants using P-elements. By creating strainscontaining only one P-element at a random site,the group could study theeffects on the fly caused bydisrupting just one easilyrecognizable place in thegenome (usually affectingonly one gene). The genomeproject adopted this methodfrom the outset, and theproject has already mutatedmore than a thousanddifferent genes.

Now that the sequencingis complete, the Spradlingand Rubin groups, withseveral additional collabora-tors, plan to redouble theirefforts on the gene-disrup-tion project. They expecttheir work to be nearlyfinished within three years.

The Department of Plant Biologyhas a long history of research into

photosynthesis using algae as a modelorganism. In 1916, Staff Member HermanSpoehr began Carnegie’s first systematicstudy of photosynthesis, using a cactus ashis model organism. But by the 1930s,algae, particularly the green algae Chlorella,was widely employed. The DesertLaboratory used Chlorella for researchbecause it grows rapidly and easily, andtolerates variation in conditions such aslight and temperature.

Research Associate Robert Emersoninitiated a study in 1937 to determine howmuch light is really needed in the photo-synthetic process. He embarked on athree-year study using Chlorella, whichyielded significant results. Emerson notedthat by illuminating the plant first withblue, then with red light, and then withblue and red light simultaneously, therewas a severe drop in photosyntheticefficiency at the far-red wavelengths. Hedetermined that the photosynthetic rate infar-red light could be enhanced bysupplemental light from shorter wave-lengths—a phenomenon later called theEmerson enhancement effect. This seemedto suggest that two separate pigmentsystems were at work, absorbing lightpreferentially at different wavelengths.This discovery was an important step tothe later recognition of two distinctphotoreactions in plant photosynthesis.

An offshoot of the photosynthesisresearch at the department occurred in thelate 1940s and early 1950s with experi-mental studies of Chlorella as a food source.In Japan at this time, scientists were alsostudying the possibility of using algae asfood, and Carnegie hosted visitinginvestigators to collaborate on the venture.The goal of this program was to enhancethe protein content of algae by manipulat-ing environmental factors. In 1951, thedepartment purposefully stopped experi-ments on the nature of photosynthesis toconcentrate on the technical developmentof algal cultures for food. CIW and theCarnegie Corporation paid a contractingfirm to build and operate a Chlorella-producing pilot plant in Massachusetts.However, the operation was troubled bycontamination in the algae growth tanksand was soon abandoned.

Chlorella is no longer used as a modelorganism for photosynthesis because itdoes not reproduce sexually and thereforeisn’t appropriate for today’s advancedgenetic research.

Algae at theDesert Lab?

Image courtesy of Carolina Biological Supply Company

Fruit Fly Genome SequencingProject Has Deep Roots

at Carnegie


Gravity measurements from the Mars Global Surveyor(MGS) indicate that more water may have flowed on the RedPlanet than was previously thought. Sean C. Solomon,director of DTM, and former DTM postdoctoralassociates Patrick McGovern and CatherineJohnson are members of a team of geophysicistswho conducted a study on the internal struc-ture of Mars. The results are published in theMarch 10, 2000, issue of Science.

The team used the MGS satellite,orbiting the planet since 1997, to map thestructure of the crust and upper mantle. Asthe surveyor orbits Mars, its speed variesbecause the difference in surface densityaffects the planet’s gravitational tug on thecraft. This speed variation creates an apparentshift in the frequency of the radio transmissionback to Earth—a Doppler shift—which in turn wasused to infer the subsurface density.

New evidence suggests there may have beenmore water on Mars than was previously thought

Louis Brown, A Radar History of World War II: Technical and Military Imperatives (Bristol andPhiladelphia: Institute of Physics Publishing), 1999, 563 pp.

To prove the truth of the old adage about World War II, “The bomb may have ended the warbut radar won it,” Louis Brown, Emeritus Staff Member at the Department of Terrestrial Magne-tism, wrote A Radar History of World War II: Technical and Military Imperatives. Brown began this workbecause he himself wanted to read a book about the development of radar, but found that therewere none. He was “struck by the absence of a comprehensive and international history of radar, ofthe kind that has appeared many times about the atomic bomb.” Brown’s book interweaves ahistory of the technologies necessary for radar development with a description of the internationaltheaters of war and the personalities of the scientists and engineers involved. To illustrate the linkbetween war and science, he looks at military campaigns from the aspect of their use of radar. The

book’s introduction alerts the reader to the technical sections so that one can choose to enjoy the story with or without thetechnical details. As a result, the book will appeal to the technically-savvy and the layperson alike.

David F. Swensen, Pioneering Portfolio Management: An Unconventional Approach toInstitutional Investment (New York: The Free Press), 2000, 366 pp.

Carnegie Institution trustee David Swensen is the author of a new book, PioneeringPortfolio Management: An Unconventional Approach to Institutional Investment. Swensen, chairof Carnegie’s board of trustees Finance Committee, draws on his 15 years of experienceas Yale University’s chief investment officer to discuss investment strategies. “Establishingand maintaining an unconventional investment portfolio carries a wide range of risks,” henotes. With this in mind, he explains how to successfully design and implement alterna-tive investment policies for institutions and universities.

The scientists found low-density regions that appear to be aseries of sediment-filled elongated channels, similar to ancient

riverbeds on Earth. These Martian channels lead from thehigher southern regions to the vast northern lowlands.

Although scientists have known about channels onMars for years, they didn’t realize how large they

were until they probed below the surface with thesurveyor. The size of the subsurface structures—more than 200 km wide, thousands of kmlong, and 1 to 3 km deep—suggests that at onetime in the past Mars may have had enoughwater to fill the lowland region with an ocean.If so, the water that carved the channels mayhave carried substantial sediments that over

millions of years completely buried thoseportions of the fluvial record at the lowest

elevations. These observations add to the growingbody of evidence that early in its history Mars was

much more similar to the Earth than it is today.

Image courtesy of NASA

NEW RE A D I N G


Sensing light

Photosynthetic, aquatic organismshave to compete for light because ofcloud cover, pollution, shade, and theabsorption of certain wavelengths bythe water column. To be successfullight harvesters, many of theseorganisms sense their light environ-ment and adjust to varying lightconditions. Grossman’s lab hasidentified a photoreceptor, as well assignal transduction elements, incyanobacteria that tells the organismwhat wavelengths of light are avail-able to use. The cells respond to thesignal by adjusting the composition ofthe pigment-proteins in their light-harvesting structures to best absorbavailable wavelengths. The photore-ceptor they identified is a proteinkinase (an enzyme involved intransferring a phosphate to anotherprotein, which may alter the activityof that protein) with a chromophore-binding site that is similar to that ofthe phytochromes. Phytochromes arephotoreceptors of vascular plants thatregulate a variety of physiologicalprocesses. This work has importantimplications with respect to theevolution of photoreceptors and theway in which phytochrome translatesa light signal into the modulation ofthe cells’ biochemical activities.

What happens with toomuch light

Other studies in the Grossman labaddress the potential toxic effects oflight. Although light is necessary forphotosynthesis, too much of it canlead to the production of reactiveoxygen species, which can damagemany processes in the cell and resultin death. During midday in Californiaa plant may be absorbing five to 10times the amount of light that can be

used for photosynthesis. For a numberof years, Olle Björkman’s laboratoryat Plant Biology examined the ways inwhich plants dissipate this excessabsorbed light energy. An oxygenatedcarotenoid pigment called zeaxanthinappears to be involved in eliminatingthis excess excitation energy as heat.The synthesis of zeaxanthin is el-evated in high light through theoperation of the xanthophyll cycle—acycle in which the carotenoid pigmentxanthophyll violaxanthin is convertedto other such pigments,antheraxanthin and zeaxanthin.Although zeaxanthin seems to beinvolved in the energy dissipation, thescientists do not know its exact modeof action.

Recently, researchers examined theproblem of energy dissipation inplants at the molecular level bygenerating mutants of both Chlamy-domonas and Arabidopsis that wereunable to dissipate excess absorbedlight energy. The scientists used a newscreen involving video imaging of thecolonies to identify mutants defectivein energy dissipation. The resultsconfirmed that the xanthophyll cycleand zeaxanthin were critical for thedissipation of excess absorbed energy,and suggested that other processesand other carotenoids might beinvolved. The investigators alsoidentified a protein component of theenergy-dissipating apparatus that isdesignated PsbS. This protein isthought to be an evolutionary precur-sor of the light-harvesting proteins ofplants. These results suggest thatenergy dissipation within the photo-synthetic apparatus arose prior to theestablishment of large light-harvestingcomplexes.

In cyanobacteria, there are smallpolypeptides related to the light-harvesting proteins of vascular plants,which are critical for survival in highlight. These proteins, called HliA(high light induced), are synthesized athigh levels when the cells are exposedto high light or to blue or UV-A light.The HliA proteins appear to bindpigment molecules and associate intomacromolecular complexes that are

integral to the photosynthetic mem-branes. The exact role of the HliAproteins in high-light survival is notknown, although they may be in-volved in energy dissipation or inbinding chlorophyll molecules andfacilitating their integration intoprotein complexes of the photosyn-thetic apparatus.

Understanding how andwhy they move

Cyanobacteria move in the waterand in films on the surface of rocks tochase the best light and nutrientconditions. Grossman wants tounderstand what generates the forcesrequired for this movement, defineenvironmental factors that controlmotility, and identify the moleculesresponsible for linking light andnutrient cues to motor function.Normal cyanobacteria move toward aunidirectional light source. Recentwork in the Grossman laboratory hasdemonstrated that this movementdepends on hair-like structures calledpili that are distributed over thesurface of cyanobacteria. Both themotility of cyanobacteria and the piliare shown on page 12. The Grossmanlaboratory has generated over 300mutant cyanobacteria that are eithernon-motile, do not respond to aunidirectional light source, or movebackward with respect to the unidirec-tional light source. By analyzing thesemutants, the researchers have identi-fied molecules that are involved inseveral processes including thebiosynthesis of pili, the generation ofcell surface architecture, the regula-tion of motor function, and thesensing of light cues. One moleculethat appears to be critical for forwardmovement contains a domain that issimilar to the chromophore-bindingdomain of phytochrome; it mayfunction in orienting the cells withrespect to the unidirectional lightsource.

One Little Cell...

continued from page 7

➤


Chlamy’s genome and NSF

Chlamydomonas is studied in morethan a hundred labs worldwide.Because this alga is an ideal modelorganism for understanding photosyn-thetic mechanisms and the ways inwhich organisms acclimate to theirlight and nutrient environments, NSFfunded the first phase of the Chlamy-domonas Genome Project in Novemberof 1999. Art Grossman is the principalinvestigator. The $3.3-million projectincludes the sequencing of cDNAs,using high density DNA microarraysto examine global gene expression in

Chlamydomonas under a number ofdifferent environmental conditionsand in certain mutant strains, analyz-ing the function of every gene on thechloroplast genome, and developing adatabase that is accessible to theinternational scientific community. Inaddition, the project will generatehundreds to thousands of physicalmarkers that will be placed on theChlamydomonas genome. Thesemarkers will allow for the efficientmap-based cloning of genes, which inturn will enable researchers to effi-

One Little Cell...

ciently probe the function andregulation of gene products. Genomicwork performed under the auspices ofthe Chlamydomonas Genome Projectwill generate knowledge to fill theevolutionary gap that separates simpleprokaryotic cyanobacteria and themore complex vascular plants likeArabidopsis and rice. It will deepen ourunderstanding of the evolution of bothspecific genes and biological pro-cesses, providing strong insights intohow we may tailor these processes tospecific environmental conditions.

These images show hownormal and a non-motile,mutant cyanobacteriumreact to a unidirectional lightsource. For the normalcyanobacterium, groups ofcells aggregate into finger-like projections that movetoward the light (A). Themutant strain shows nomovement (B). At highermagnification (~125x) of thenormal cyanobacterium,individual cells in a singlefinger-like projection appearto aggregate at the tip of theprojection (C). The mutantcyanobacterium (D), on theother hand, makes tight,non-spreading colonies. Ateven higher magnification(25,750x) in whichindividual cells are viewed,the normal cell (E) exhibitsthin and thick pili on the cellsurface; these structuresgenerate the forces thatallow the cyanobacterium tomove. The non-motilemutant (F) has an overabundance of the thick pilion the surface of the cell,which in some way preventsit from moving.


In Brief...TRUSTEES

John Diebold’s entrepre-neurial project completed a casestudy of New York’s SiliconAlley.

ADMINISTRATION

On April 30, Maxine Singerwas inducted into the Washing-ton, D.C. Hall of Fame for“outstanding scientific accom-plishments and deep concern forthe societal responsibility ofscientists in Washington, D.C.”At Bryn Mawr College, also inApril, she delivered the 1999-2000 Rothenberg Lecture inBiology and Public Policyentitled “Catching Up.” Shedelivered the 2000 Dael L.Wolfle Lecture at U. Washing-ton–Daniel J. Evans School ofPublic Affairs entitled “Scienceand the Public: Playing Catch-Up.” On May 11 she was thekeynote speaker for theWhitehead Institute’s PolicySymposium dinner and delivereda talk on “Genes and Greens.”On May 21 she was a speaker atYale University’s GraduateSchool of Arts and SciencesCommencement Convocation.Her speech was entitled“Challenges Facing the NewlyElite.”

OBSERVATORIES

François Schweizerattended an AURA Observato-ries Council meeting in LaSerena, during which councilmembers were shown theGemini South 8-m telescopeunder construction on CerroPachon. He took the opportunityto also visit Las Campanas andsee firsthand the rapid progresson Magellan I and II. He helpedorganize the ESO/CTIO/LCOInternational Workshop, “Stars,Gas and Dust in Galaxies,” heldin La Serena in March and theconference “Gas and GalaxyEvolution” in honor of the 20thanniversary of the VLA, held inSocorro, N.M., in May 2000.

In April, Wendy Freedmangave an invited review at ameeting at the Space TelescopeScience Institute and at theJohnson Space Center. She alsogave colloquia at Stanford,Berkeley, and Cornell, and saton the Caltech Visiting Commit-tee for Math, Physics, and

Astronomy, a committee chairedby Carnegie trustee emeritusCharles Townes. Carnegietrustee Sandra Faber was also amember of the committee. OnApril 17, she presented theMathematical and PhysicalSciences Distinguished Lecturein Astronomy at the NationalScience Foundation, entitled“Determination of the HubbleConstant, for better or worse.”Wendy has been elected a Fellowof the American Academy ofArts and Sciences.

In March, Steve Shectmanpresented a paper summarizingthe present status of theMagellan Project at the confer-ence “Astronomical Telescopesand Instrumentation 2000,” heldin Munich, Germany.

Jason Prochaska attendedthe SPIE conference in Munichand gave an invited talk onchemical abundances in thedamped Lyalpha systems.

Andrew McWilliam gavetalks on the chemical composi-tion of the galactic bulge andSagittarius dwarf galaxy at OhioState U. and at U. Washington.

Hubble Fellow ScottTrager’s topic was “Thetimescale of galaxy formation:the stellar evidence” in invitedlectures at the Institute forTheoretical Physics, UC-SantaBarbara, U. Hawaii, U. Texas-Austin, and UC-Irvine.

EMBRYOLOGY

In April, DonBrown chaired theInternationalAdvisory Board tothe Wellcome/CRCInstitute in Cam-bridge, U.K.

Marnie Halperncoorganized the ColdSpring Harborzebrafish meetingheld in April 2000.The front page of theMarch 15 BaltimoreSun featured anarticle about the

Halpern lab.Doug Koshland was elected

to membership in the AmericanAcademy of Arts and Sciences.

Shikha Laloraya has taken ajob as an assistant professor inthe Department of Biochemistry,Indian Institute of Science,Bangalore, India.

On April 29, Sofia Robb, aresearch assistant in the SánchezAlvarado lab, married TomTurlington.

Alejandro SánchezAlvarado and Brigitte Galiot

cochaired thesession onmetazoan regenera-tion at the Societyof DevelopmentalBiology’s 59th

annual meeting inBoulder, Colo., inJune 2000. He alsowas an invitedspeaker at the IX

International Symposium on theBiology of Turbellarians inBarcelona, Spain, in June.

On Thursday May 4, DanielBarbosa Fraker was born toDaniela Drummond-Barbosaand Russell Norton Fraker.

Postdoctoral fellow NicoleGrieder has returned to theBiozentrum in Basel, Switzer-land, where she will continue herstudies of Drosophila oogenesis.

PLANT BIOLOGY

Winslow Briggs presented aseminar, “Phototropin: aphotoreceptor kinase mediatingphototropism in higher plants,”at the Stazione Zoologica,Naples, and at the universities ofRome, Lausanne, and Geneva.Winslow coorganized and spokeat the Gordon-sponsoredMeeting on Photoreceptors andSignal Transduction held in IlCiocco, Italy, April 30-May 5.

In January, Chris

Somerville participated in aworkshop at the Salk Institute todraft a 10-year plan for goals inplant genome research. TheNational Science Foundation hasincorporated the document,entitled “The 2010 Plan,” into itslong-term research funding plan.Transcripts of Chris Somerville’slecture entitled “The scientificbasis of plant genetic engineer-ing,” presented at a Januarysymposium in The Hague andorganized by U.S. AmbassadorCynthia Schneider on behalf ofthe State Department, can befound at http://www.usemb.nl/bioproc.htm. In February, Chrispresented a talk at Cornell U.entitled “The next phase of theplant genome project.” InMarch, Chris presented theLemieux Lecture, “Geneticdissection of plant lipid metabo-lism,” at U. Alberta. In April, hepresented the Thornton-MasaLecture, “The case for GMOs,”at Colorado State U. Finally, inMay Chris presented a seminarentitled “The rubber problem” atthe Defense Research Agency inWashington, D.C.

In April, Arthur Grossmanpresented two seminars atIndiana U.: “Integration ofenvironmental signals in theacclimation of cyanobacteria”and “The control of phosphorusdeprivation responses inChlamydomonas reinhardtii.”Devaki Bhaya also presented aseminar at Indiana, “One smallstep: motility in cyanobacteria.”On April 17, Art gave a seminarat Paradigm Genetics, hosted byformer staff member NeilHoffman.

In February, Art Grossmanwas granted U.S. Patent#6,027,900 for “Methods andtools for transformation ofeukaryotic algae.” Art was alsoawarded a $21,000 NSF bi-national grant (with DanielVaulot in Roscoff, France) for his

proposal, “Analysis of

On May 9, the departmenthosted a meeting of the BayArea Biosystematics Workinggroup, organized by BrentMischler (UC-Berkeley) andChris Somerville. In a briefoverview, Brent explainedthat this meeting, started inthe 1930s, has its historicalroots with Carnegie’staxonomists and geneticistsduring the time of Clausen,Keck, and Hiesey.

Embryology’s YixianZheng won a nationwidecompetition to beappointed a HowardHughes Medical InstituteInvestigator.


In Brief...

gene expression during acclima-tion of cyanobacteria to stressconditions.”

Jo-Man Wang, a technicianin Shauna’s lab, and Yeu-ShyrWu welcomed their son, Aaron,born April 11.

In March, Sarah Fisherjoined the Somerville labs as alab technician.

Anne Krapp and CatherineMueller, Visiting Researchersfrom U. Heidelberg, arrived fora month’s stay in March tocollaborate with Wolf Scheible.

Mark Stitt (U. Heidelberg)arrived in March for a five-month sabbatical to work withChris Somerville.

Rogene Gillmor is workingin the Somerville lab as avolunteer.

Chris Henderson joined TheArabidopsis InformationResource group (TAIR) inMarch as an assistant program-mer.

Trevor Swartz (UC-SantaCruz) joined the Briggs lab as apostdoctoral research associateto do spectroscopic studies onphototropin.

In April, Warren Nott joinedthe Field lab as a lab assistant,and Isabell Buttron (U.Freiburg) joined the Ehrhardt labas a visiting researcher.

Margaret Olney will be anassistant professor in the biologydepartment at Colorado Collegethis fall. Margaret will finish thesummer at the Briggs lab to wrapup her thesis work.

Gundolf Kohlmaier, avisiting researcher in ChrisField’s lab, left in February to

return to U. Frankfurt.Ken Keegstra left after

spending a three-monthsabbatical with ShaunaSomerville. Pam Green left afterspending a six-week sabbatical.

TERRESTRIALMAGNETISM

Sean Solomon was elected amember of the NationalAcademy of Sciences on May 2at the 137th annual meeting of theacademy. Election to member-ship recognizes “distinguishedand continuing achievements inoriginal research.” He was one of60 new members chosen.

Former DTM research staffmember Albrecht Hofmannwas inducted as a ForeignAssociate at the NAS meeting.Dr. Hofmann, one of 15 ForeignAssociates elected to theacademy last year, is director ofthe Max Planck Institute forChemistry in Mainz, Germany.

Erik Hauri received theJames B. Macelwane Medal fromthe American GeophysicalUnion at the Spring AGUMeeting. The medal “recognizes

significant contribu-tions to the geophysi-cal sciences by anoutstanding youngscientist (less than 36years of age).”

In April, SelwynSacks and AlanLinde visited theMontserrat VolcanoObservatory withBarry Voight (PennState). The objectivewas to determine thefeasibility of initiatinga collaborativeprogram in which asmall array ofborehole strainmeters

and seismometerswould be installed onthe island.

Vera Rubin visitedthe U. Illinois andArizona State U.

astronomydepartments thisspring, where shepresentedcolloquia andvisited with groupsof faculty,students, andwomen in science.Former DTMpostdoctoralfellows Linda

Stryker and David Burstein arenow at ASU, where Burstein iscurrently president of theuniversity senate. In April,Rubin addressed the NationalScience Teachers Association inOrlando on the subject “Con-necting to the Universe.” PennState-Lehigh Valley campusscience faculty has named theiracademic award, to be presentedannually, the Vera C. RubinAward for Excellence. Rubin wasthe keynote speaker andpresented the first award toastronomy student KevinGordon.

In March, Alan Bossdelivered the George C. BensonMemorial Lecture, “Extrasolarplanets,” at Miami U. (Oxford,Ohio). In April, Boss reviewedthe role of magnetic fields infragmentation at the IAUSymposium 200: The Formationof Binary Stars, held in Potsdam,Germany. Boss described sciencegoals for NASA’s TerrestrialPlanet Finder (TPF) at the BallAerospace/TPF Science TeamMeeting, held at the SpaceTelescope Science Institute inBaltimore.

Sean Solomon chaired theExternal Advisory Committeefor Geology and Geophysics atRice U. in March, and the Earthand Environmental SciencesDirectorate Review Committeeat Lawrence Livermore NationalLaboratory in April. In May hedelivered the first lecture in theDiscoveries of the 20th Centuryseries at the SmithsonianInstitution in celebration of the50th anniversary of the NationalScience Foundation. He alsogave invited papers at theGeneral Assembly of theEuropean Geophysical Society inApril and at the Fourth Confer-ence on the Low-Cost PlanetaryMissions of the InternationalAcademy of Astronautics inMay.

DTM attendees at the Lunarand Planetary Science Confer-ence in Houston in March

included Alan Boss, ErikHauri, Sean Solomon, GeorgeWetherill, and postdoctoralfellows Satoshi Inaba, StephenKortenkamp, and HarriVanhala.

Alan Boss, Sean Solomon,George Wetherill, andpostdoctoral fellow KennethChick attended the First AnnualAstrobiology conference, held atNASA Ames, Moffett Field, inApril.

Paul Silver gave an invitedtalk at the annual meeting of theSeismological Society of Americameeting in San Diego.

On March 29, Paul Butler,Geoffrey Marcy (UC-Berkeley),and Steven Vogt (UC-SantaCruz) announced the first twosub-Saturn mass extrasolarplanets at a NASA pressconference. Alan Boss alsospoke at the event. The story wascarried in the New York Times, theWashington Post, Science News, andon CNN. The discovery paperfor this work has been acceptedby the Astrophysical Journal Letters.On April 21, Butler, Marcy, andVogt announced planets aroundtwo metal-rich stars.

In March, Paul Butler gavethe annual invited popular talk atthe New York Center for Studieson the Origins of Life. In April,he gave the astronomy collo-quium at U. Virginia and aplenary talk at the AmericanPhysical Society annual meeting.In May, he gave astronomycolloquia at the CIW Observato-ries and the Space TelescopeScience Institute.

Jon Aurnou, a geophysicalfluid dynamicist who receivedhis Ph.D. from Johns HopkinsU., was appointed a postdoctoralassociate in April.

Jocelyn Bell Burnell was theMerle A. Tuve Senior Fellow atDTM for the month of May. Aradio astronomer and professorof physics at the Open Univer-sity, England, she is best knownas the discoverer of the firstradio pulsars, subsequentlyshown to be rapidly rotatingneutron stars. Dr. Bell Burnellvisited DTM the week of May 8.She gave the DTM seminar andparticipated in a number ofdiscussions with staff andpostdocs during her stay.

Visiting Investigator Suzanvan der Lee arrived in May fora month to work with DavidJames and Paul Silver on upper-mantle structure under South

George Wetherill was therecipient of the J. LawrenceSmith Medal and Prize ofthe National Academy ofSciences, awarded at theMay meeting. The awardrecognizes recent originaland meritoriousinvestigations in meteoritics.

Shown (from left) on May 3 at a Broad BranchRoad reception honoring Sean Solomon on hiselection to the National Academy of Sciencesare NAS members Albrecht Hofmann andCarnegie’s Ho-kwang Mao, George Wetherill,Solomon, Vera Rubin, Hatten Yoder, MaxineSinger, and Francis Boyd.


In Brief...America and southern Africa. Aformer DTM postdoctoral fellow,she is now on the faculty at theInstitut für Geophysik, Zurich.

Predoctoral Fellow SueWebb, from the U.Witwatersrand, arrived in Aprilfor a two-month visit. She iscontinuing work begun last yearwith David James on combiningsouthern African gravity,magnetic, and seismic data setsas part of the Southern AfricaSeismic Experiment.

LeAnn Nicole Bartholomewwas born on May 12 to machin-ist-instrument maker RichardBartholomew and his wife,Loretta.

DTM/GL

Library Assistant Merri Wolfwas elected to the board ofdirectors of the InterlibraryUsers Association in March. TheAssociation is a 50-membercooperative organization ofspecialized libraries in theNational Capital area.

Two rare 17th-century starcharts were presented to theDTM-GL library by Vera Rubinin February. Prepared by theastronomer Johannes Hevelius ofDanzig in 1686, the charts areprized for their beautifullyengraved figures of the constella-tions and their elaborate cornerdecorations. Rubin also donateda biography of Heveliuscontaining a bibliography of hispublished works.

GEOPHYSICALLABORATORY

In April, participants in theNational Junior Science andHumanities Symposium visited

the Broad Branch campus.Constance Bertka, SteveShirey (DTM), and HatttenYoder led the students on a tourof the facilities and spoke withthem about preparing for acareer in science.

George Cody presentedinvited talks at Penn State onbiogeochemistry at nanoscalesusing soft x-ray microscopy, andat George Washington U. ongeochemical roots of life. He alsopresented a poster at theAstrobiology Conference at theNASA Ames Research Center.

Gözen Erten (GeorgetownU. Medical Center) has beenappointed a Visiting Investigator.Dr. Ertem will conduct researchwith Bob Hazen on the selectiv-ity of asymmetric crystallineminerals towards chirality inbiological oligimers.

Wes Huntress has beenelected to the board of directorsof the Association of Universitiesfor Research in Astronomy, Inc.(AURA) for a three-year term,effective July 1, 2000, throughJune 30, 2003. In April, Wesreceived the Federal DesignAchievement Award for theMars Pathfinder Mission. Thisaward is given in recognition ofcontribution to excellence indesign for the federal govern-ment. He has also been electedan academician in the Interna-tional Academy of Astronautics

and delivered the inauguraladdress, “Discoveries: a basis fornew challenges,” to the academyon May 9 in Washington, D.C.

Wes Huntress has beenteaching a graduate-level courseon astrochemistry at the BBRcampus. The course examineschemical evolution from atomsin the interstellar radiation fieldto complex organic moleculesand aggregates in the early solarsystem.

Wes Huntress and MarilynFogel were hosts to the Work-shop on Life Detection, heldApril 25-26 at Carnegie’sadministration building. Theworkshop was sponsored by theNational Research Council andresponds to NASA’s request for acomprehensive and interactiveworkshop that updates newtechniques for detectingextraterrestrial organisms andtheir biosignatures. A dinnerparty was held at GL on April25; many of the attendees touredthe lab afterwards.

Robert Hazen was theHumana Distinguished VisitingProfessor at Centre College inDanville, Ky., where hepresented a series of five lectureson aspects of the origin andevolution of life. He presentedtwo keynote lectures at asymposium at McPhersonCollege, Kans., on evolution andcreationism. Hazen alsopresented seminars on mineralsand the origin of life at StanfordU., U. Connecticut, the Learningin Retirement Institute of GeorgeMason U., and jointly toCarnegie’s Department ofEmbryology and Johns HopkinsU.

Russell Hemley gave talks atOhio State U., the Center forSolid State Sciences (ArizonaState U.), UC-Santa Cruz, and atthe Max-Planck Institute,Stuttgart. Hemley also attended ameeting at the Institute for Studyof the Earth’s Interior in Misasa,Japan. In March, he gave aninvited talk at the Physical

Chemistry at High PressureSymposium of the AmericanChemical Society. He was the co-convenor of the High PressureNeutron Scattering Workshop,Argonne National Laboratory, inApril. In May, he gave aninvited talk at the VerkinInstitute 40th-anniversarymeeting in Kharkov, Ukraine.

Charles Prewitt attendedthe Experimental Mineralogy,Petrology, and GeochemistryConference in Bergamo, Italy,and presented an invited paper,“Crystal chemistry of Ca/Srmetasilicates andmetagermanates.”

As a graduate of U. Chicago,Hatten Yoder received theirProfessional Achievement Awardfor his distinguished record ofprofessional accomplishmentsand leadership, which havereflected credit upon theuniversity and its alumni.

GL’s Matthew Wooller andMarilyn Fogel, former fellowsSue Ziegler (U. Arkansas) andMark Teece (SUNY-ESF), andVisiting Investigators NoreenTuross (Smithsonian Inst.) andDiane O’Brien (Stanford U.)presented papers on variousaspects of ecological research atthe 2nd Isotopes in EcologyMeeting held in Braunschweig,Germany. All of their researchwas conducted on GL’s newisotope mass spectrometer.

Doug Rumble’s recentVisiting Investigators are HideMasago (Tokyo Inst. Technol-ogy), David Gorges (U.Lausanne), Uwe Wiechert (ETH-Zurich), and Being Change(Chinese Academy of GeologicalSciences, Beijing).

In April, Jie Li, Yingwei Fei,and Bill Minarik journeyed toKobe, Japan, to use the Spring-8synchrotron facility. They werejoined there by former GLresearchers Kei Hirose andMike Walter. The teammanaged to complete 10successful multianvil runs in arow within four 24-hour days.After the experiments, they werehosted at the home of Mike, PruFoster (formerly at DTM), andtheir son Dakota. Pru also worksat Okayama U.

Yangzhang Ma and his wifeFengru Wu welcomed DarwinBolun to their family, bornMarch 31.

The DTM/GLlibrary’s 1914-era readingroom wasrenovated thiswinter. Amongthe featuresof therenovation are furniture appropriate to the period, and historicartifacts. The space serves as a pleasant setting for quiet study andsmall meetings of researchers from both departments.

David James(center), withtechnician Pat Ryan(left) and professorDouglas Toomey(right) (U. Oregon),examine seismicfield data aboardthe fishing boat,Golondrina, in theGalapagos Islands.Ryan, James, Toomey, and Kristen James (photographer) spent threeweeks in the Galapagos in late March and early April servicing the 10Carnegie broadband portable stations of the IGUANA SeismicProject in the Galapagos Islands. The project, of which professorToomey is PI, is a joint venture between the U. of Oregon and DTM.


$

CARNEGIE NOW A

TRIPLE-A INSTITUTION

In April, Moody’s upgraded Carnegie’s long-termdebt rating from Aa1 to Aaa. Only six other not-for-profits and 15 universities and colleges have attainedthis same high rating. The institution’s unrestrictedfinancial resources are more than 10 times greater thanthe debt, “a level surpassed by few organizations evenin the Aaa category,” says Moody’s. Other reasons therating was upgraded include insulation from the studentmarket and other economic risks, and manageablefuture borrowing plans. Moody’s sees a bright future forthe institution, expecting it to continue “its powerfulfinancial position indefinitely.”

Capital Science Lecture Series2000-2001

The speakers for next season’s Capital Science Lecture Series are listedbelow. All lectures are on Tuesday evenings starting at 6:30 p.m. at theCarnegie Building, 1530 P St., N.W., Washington, D.C.

October 3, 2000 Kenneth NealsonCalifornia Institute of TechnologyEarly life microbiology

October 24, 2000 R. Paul ButlerDepartment of Terrestrial MagnetismExtrasolar planets

November 28, 2000 Sallie Watson ChisholmMassachusetts Institute of TechnologyPhytoplankton and global change

January 30, 2001 Neta A. BahcallPrinceton UniversityCosmology

February 27, 2001 Cindy Lee Van DoverThe College of William & MaryHydrothermal vent biology

March 20, 2001 William T. NewsomeHoward Hughes Medical Institute andStanford University Medical CenterNeuronal plasticity

April 17, 2001 S. George PhilanderPrinceton UniversityWhy global warming is controversial

* Schedule subject to change Photo by Anice Hoachlander

CARNEGIE TO BRING THE NEW SCIENCE OF

ASTROBIOLOGY TO CLASSROOMS WORLDWIDE

As a part of NASA’s Astrobiology Institute, CASE will launchan interactive educational Web site dedicated to the new scienceof astrobiology—the study of how life originated and thrives onEarth and how we may find it elsewhere. The site is geared toelementary and middle school teachers and students. Thecontent, which will appear on the site over the next two years,will be based on three themes drawn from astrobiology. The firsttheme will focus on Earth’s environments and chemistry and willlead Web surfers to the second theme—life in space. The thirdtheme will use the information from the other two segments todetermine what components and conditions are really needed forlife to arise and thrive anywhere. The Web site will be availablelater this summer at www.ciw.edu/leaf.

� �

WHERE TO WATCH PLANTS AT WORK

David Ehrhardt at Plant Biology has unveiled aunique Web site where the dynamic processes inlive plant cells can be viewed with the aid of time-lapse imagery. This imaging is made possible byintroducing a green fluorescent gene from a jelly-fish into Arabidopsis thaliana and viewing theresults with confocal microscopy. To see the imagesof plants at work on the evolving site, go to http://deepgreen.stanford.edu.

Planning for the Carnegie Centennial Exhibition is well underway. This show, which will celebrate a century of Carnegie scienceby displaying a range of images and objects from the institution’spast, will be installed on the second floor of the administrationbuilding from December 2001 through May 2002. It will be opento the public as well as to invited groups.

We are planning a number of programs and lectures toaccompany this exhibition. While attracting visitors to the show,these events will also provide opportunities to explore in greaterdepth various issues relating to Carnegie science—past, present,and future.

YOU CAN HELP! Are you aware of any academic orprofessional meetings scheduled to be held in D.C. during thetime of the exhibition? We are eager to communicate with a rangeof audiences, including those without—as well as those with—scientific training. If you know of such a group, please contactMargee Hazen at [email protected].

CE N T E N N I A L N E W S

The Carnegie Institution of Washington is committed to the nationalpolicy of fair treatment of all employees in all aspects of employment. TheInstitution does not discriminate against any person on the basis of race,color, religion, sex, national or ethnic origin, age, disability, veteran status,or any other basis prohibited by applicable law. This policy covers allprograms, activities, and operations of the Institution, including adminis-tration of its educational program, admission of qualified students asfellows, and employment practices and procedures.

S P E C T R A - Carnegie Institution for Science...S P E C T R A Summer 2000 THE NEWSLETTER OF THE CARNEGIE INSTITUTION Department of Plant Biology Department of Terrestrial Magnetism

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