01. DNA Structure and Organization
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 1/55
01. DNA Structure and Organization
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 2/55
Griffith – 1928 – Transformation experiments
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 3/55
Hershey and Chase – 1952 - Transduction
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 4/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 5/55
DNA is a polar polymer 5’ Ph43’ OH
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 6/55
Informação adicional:
1. Densidade da molécula nativa muito alta
2. Decomposição da molécula nativa em nucleótidos resultava emque as proporções dos diferentes componentes eram sempre:
Guaninas = Citocinas Adeninas = Timinas
3. A molécula nativa tinha um diâmetro constante (20 Å)
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 7/55
α β γ
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 8/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 9/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 10/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 11/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 12/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 13/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 14/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 15/55
Estabilidade do DNA
Interações hidrofóbicas entre as basesque resultam na sua orientação principalmenteperpendicular ao eixo da molécula.
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 16/55
Desnaturation e renaturation do DNA
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 17/55
DNA melting curves
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 18/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 19/55
Southern blotting
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 20/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 21/55
Estrutura secundaria do DNA
Linear DNA molecule
Região de dupla simetria com sequenciasrepetidas invertidas
Positive supercoiling
Link number = 0
Link number = 3
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 22/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 23/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 24/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 25/55
Nucleossoma
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 26/55
Modelos da organização da cromatina
Bead on a string 11 nm
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 27/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 28/55
Modelos da organização da cromatina
Solenoid 30 nm
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 29/55
Remodelação da cromoatina
Dependente do ATP
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 30/55
Diversas proteínas interatuam com o DNA
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 31/55
C-terminal das histonas
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 32/55
O Código epigenético
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 33/55
O Código epigenético
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 34/55
1
6-7
40
680
1.2 x 104
Packingratio
Organização do DNA nu núcleo
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 35/55
Scaffold Matrix
Mitotic Interphase (nucleus)
The chromosome Scaffold
Remover DNA com nucleases e DNA com NaClProteínas não histonasTopoisomerase IIStructural Maintenance of Chromosomes SMCs
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 36/55
Codensin is involved in the organization of mitotic chromosomes
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 37/55
Cohesin maintains sister chromatids together from G1 to end of Mitosis
DNACondensinCohesin
Cornelia de Lange Syndrome
(1/10,000) severe developmental deffects
Mutations at SMC1/3 or SCC2 (chaperone of SCC1)
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 38/55
Genoma de um organismoChromosome painting
1 N = Haploide2 N = Diploide
Control cancer cell
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 39/55
Chromosome territories in human cells
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 40/55
Gene localization changes within the nucleous in response to transcription
Genomics
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 41/55
Genomics
DNA complexity
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 42/55
DNA complexity
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 43/55
25,000
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 44/55
Tipos de sequencias no genoma
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 45/55
Repeats Transpose Repeat
TE
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 46/55
Transposons
Barbara McClintock 1902-1992
Nobel prize of Physiology and Medicine 1983
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 47/55
Transposition
- Normalmente reprimida- Pode ser activada- Induz alterações em genes- Induz quebras cromossomicas
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 48/55
Transposons
“copy paste via RNA or DNA”
Transposões podem inativar genes
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 49/55
Transposões podem inativar genes
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 50/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 51/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 52/55
Heterocromatina
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 53/55
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 54/55
O Genoma humano
SINEs: Short Interspersed Nuclear Elements
- Short <500 b- Transcribed by RNA pol III- Non-coding- Alu sequences (280 bp) cut RE Alu- 1,5 M copies- Use TEs for mobilization
LINEs: Long Interspersed Nuclear Elements
- Heterogenous in lenght- Transcribed by RNA pol II- Code for reverse transcriptase and endonuclease- 500,000 copies- Move by coping so enlarge the genome
7/28/2019 01-DNA structure.pdf
http://slidepdf.com/reader/full/01-dna-structurepdf 55/55
Related Documents
