PCL477H1-Lecture 5a to post [Compatibility Mode]

PCL477H1-Lecture 5a to post [Compatibility Mode] - Lecture...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
ecture 5 overview Lecture 5 overview oncept of DNA double- rand breaks (DSB) concept of DNA double strand breaks (DSB) • strand breaks produced by clastogenic agents rand breaks produced by endogenous strand breaks produced by endogenous processes athways of double- trand break repair pathways of double strand break repair • pathways single-strand break repair ow can we study strand break repair how can we study strand break repair • consequences of defective double-strand reak repair break repair
Background image of page 1

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

View Full DocumentRight Arrow Icon
NA Strand break concept DNA Strand break concept •d a m a ge to DNA bases -potential to alter coding information in the genome utagens agents that - mutagens : agents that result in DNA base damage • damage to the DNA double-helix backbone -fracture of the sugar- phosphate backbone clastogens: agents that result in DNA backbone amage damage
Background image of page 2
Double-strand breaks ow are they formed? How are they formed? (gimme a break) 1. Naturally occurring DNA transactions Telomeres – chromosome terminals DNA rearrangements in the immune system xchange of genetic information between homologous chromosomes Exchange of genetic information between homologous chromosomes 2. DNA backbone damage by radiation or chemicals alkylation of phosphates oxidative damage to sugars 3. DNA damage that results in compromised or failed replication of DNA or segregation of DNA e.g. Stalling and collapse of replication forks – single- and double-strand breaks induced when DNA replication fork encounters a damaged mplate/single tranded break in the template template/single-stranded break in the template e.g. segregation of daughter chromosomes during anaphase may result in DSBs due to mechanical shearing of cross-linked DNA
Background image of page 3

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

View Full DocumentRight Arrow Icon
DNA strand breaks caused by antineoplastic drugs and xenobiotics Alkylation of phosphates groups in DNA backbone: -any alkylating agent that can react with DNA base has potential for creating adduct with phosphate group xidative damage to DNA sugars: Oxidative damage to DNA sugars: -about 20% of hydroxyl radicals that react with DNA attack the sugars in the
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/03/2010 for the course PHAMACOLOG pcl470 taught by Professor Arnot during the Fall '10 term at University of Toronto- Toronto.

Page1 / 24

PCL477H1-Lecture 5a to post [Compatibility Mode] - Lecture...

This preview shows document pages 1 - 5. Sign up to view the full document.

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