DNA->RNA-> Protein The Central Dogma Replication-> Transcription-> Translation Modified from Kim Foglia
Jan 22, 2016
DNA->RNA-> Protein
The Central DogmaReplication-> Transcription-> Translation
Modified from Kim Foglia
Bodies are made up of cells All cells run on a set of
instructions spelled out in DNA ( deoxyribonucleic acid)
Bodies Cells DNA
How does DNA code for cells & bodies? DNA synthesized ( REPLICATION)->RNA-> proteins->cells
DNA Cells Bodies
DNA has the information to build proteins genes
DNA Proteins Cells Bodies
proteinscells
bodiesDNA gets all the glory,Proteins do all the work
cytoplasm
nucleus
Cell organizationDNA
DNA is in the nucleus▪ genes = instructions for making proteins
want to keep it there = protected▪ “locked in the vault”
Building the polymer
Nitrogenous bases 2 types of nucleotides
different nitrogen bases purines▪ double ring N base ▪ adenine (A)▪ guanine (G)
pyrimidines▪ single ring N base ▪ cytosine (C)▪ thymine (T)▪ uracil (U)
Purine = AGPure silver!
Base Pairs Nucleotides bond between
DNA strands H bondsphosphodiester bonds purine :: pyrimidine A :: T▪ 2 H bonds
G :: C▪ 3 H bonds
Matching bases?Why is this important?
Passing on DNA information
Need to get DNA gene information from nucleus to cytoplasm need a copy of DNA messenger RNA
nucleus
cytoplasm
ribosome
mRNA
buildproteins
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DNA vs. RNADNA
deoxyribose sugar nitrogen bases
G, C, A, T T : A C : G
double stranded
RNA ribose sugar nitrogen bases
G, C, A, U U : A C : G
single stranded
Transcription ( DNA->RNA)
Making mRNA from DNA DNA strand is the
template (pattern) match bases▪ U : A▪ G : C
Enzyme RNA polymerase
RNA structure
Ribonucleic acid RNA nucleotide ( ribose, phosphate,
AUCG) Phosphodiester bonds Synthesis ( transcription) nucleolus
Types of RNA
Messenger RNA: carries coded instruction for protein synthesis
Transfer RNA: carries specific amino acids to ribosomes during protein assembly
Ribosomal RNA: part of ribosomes
How does mRNA code for proteins
mRNA leaves nucleus mRNA goes to ribosomes in
cytoplasm Proteins built from instructions on
mRNA
aa aa aa aa aa aa aa aa
mRNA
U C CCCCCA A U G U G A A A A AG G G GU U
Cell organization Proteins
chains of amino acids made by a “protein factory” in cytoplasm protein factory = ribosome
nucleus
cytoplasm
ribosome
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buildproteins
How do proteins do all the work
Proteins proteins run living organisms enzymes▪ control all chemical reactions in living
organisms structure▪ all living organisms are built out of proteins
Proteins
Building block =
aminoacid
aminoacid–
aminoacid–
aminoacid–
aminoacid–
—N—H
H
H|—C—|
C—OH
||O
variable group
amino acids
20 different amino acids
Amino acid chains Proteins :amino acids chained into a
polymer, primary structure held by peptide bonds
Each amino acid is different some “like” water & dissolve in it some “fear” water & separate
from it
amino acid amino acid amino acid amino acid amino acid
Protein structure
Primary structure: chain of amino acids held by peptide bonds
Sensitive to temperature, pH and ionic conditions
Protein synthesis occurs on ribosomes
DNA Replication
mRNA
From nucleus to cytoplasm
DNA
transcription
nucleuscytoplasm
translation
trait
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protein
From gene to protein
transcriptiontranscription
translationtranslation
proteinprotein