Lecture 2 MCB121

Lecture 2 MCB121 - Lecture 2 MCB121 MBOG pp 144-152;...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Goals: 1. you will be able to describe the levels of chromosome structure from the 10 nm fiber to the metaphase chromosome 2. You will be able to distinguish characteristic features of euchromatin and heterochromatin 3. You will be able to associate histone variants with their cellular function 4. you will be able to outline the steps of chromatin immunoprecipitation (ChIP) 5. you will be able to analyze ChIP-seq data I. Chromosome Structure (DNA) -Chromosome is the nucleic acids and proteins that are required to replicate and segregate genetic material ( About one half the mass of a chromosome is comprised of a single DNA molecule. The other half is made up of proteins including histones, topoisomerase, condensin and cohesin.) -metaphase- chromosome in most compact phase -we have 22 pair of autosomes, and one pair of sex chromosome. Each pair has chromosome that come from mom and one from dad total of 46 chromosomes -metaphase chromosomes when replicated (2 homologous chromosomes), has sequences that is required for replication --centromere --telomeres for chromosomes maintenance --origins of replication – non coding regions of the chromosome --each chromatid is one molecule of DNA, one continuous strand without interruption G1(2n) (s phase-DNA replication) G2(4N) mitosis G1 (2n) -mitosis generate 2 - 2n G1 cells, 2n can be generated by haploid (egg and sperm) come in to form the gamete -2n gets converted to haploid gametes A. Overall chromosome structure depends on the cell cycle stage -mitotic chromosome at most condensed state -interphase chromosomes are diffused and loosest, and condenses at metaphase (interphase is everything except mitosis) -change from interphase to metaphase when cells undergo mitosis -compact to segregate, start to align and separate at anaphase and condense again -homologous chromosomes don’t always occupy the same space B. Chromosomes are nonrandomly organized in the nucleus. -Each chromosome seems to occupy it's own territory in the nucleus. Don’t intermingle -Centromeres, telomeres, silent DNA (heterochromatin) tends to be located at the nuclear periphery while actively transcribed DNA is generally located toward the center of the nucleus. C. Packaging of chromatin relative to B-form DNA (~10bp/turn)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/06/2011 for the course MCB 121 taught by Professor Gasser during the Winter '09 term at UC Davis.

Page1 / 6

Lecture 2 MCB121 - Lecture 2 MCB121 MBOG pp 144-152;...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online