BIOL308 Lecture Notes - Lecture 9: Ploidy, Integrase, Rad52
1 Jun 2017
School
Department
Course
Professor
Document Summary
1: non homologous end joining: when both strands are simultaneously broken at the same place so there is no undamaged template. A: error prone repair where ends of broken dna are ligated together. B: heterodimers (ku70/80) find and hold the ends together. C: dna protein kinase catalytic subunits (pkcs) are recruited by ku70/80 and phosphorylated. D: artemis (endo/exonuclease) is activated and trims overhangs/cleaves hairpins. F: dna ligase 4 and xrcc4 joins the ends. *this is less accurate than homologous recombination repair which uses the sister chromatid sequence. 2: multigene sos trans-lesion repair: enables cell survival but with a higher mutation risk rate (inducible, not constitutive) A: bypass dnaps used since they have low processivity, are conserved, and have high error rates. E. coli: umuc part of dnap5, has a high error rate and easily releases dna. B: dnap zeta, eta, iota, kappa, lambda are switched to bypass t dimers.
