250 likes | 559 Views
Chapter 10. Homologous Recombination. 27 and 29 September, 2004. Overview. Homologous recombination relies on regions of nearly identical sequence. The Holliday model of the mechanism of recombination involves recognition, strand invasion, branch migration, and resolution.
E N D
Chapter 10 Homologous Recombination 27 and 29 September, 2004
Overview • Homologous recombination relies on regions of nearly identical sequence. • The Holliday model of the mechanism of recombination involves recognition, strand invasion, branch migration, and resolution. • The Double-strand Break Repair model is similar, but involves two Holliday junctions. • Homologous recombination is mediated by protein enzymes. • RecA (Rad51p) pairs homologous regions and promotes strand exchange. • RecBCD (Rad 50/58/60p; MRXp) generates single strand for invasion. • RuvAB and RuvC (?) promote branch migration and resolution. • Homologous recombination is required for successful meiosis. • In meiosis, Spo11 generates DSB, MRXp extends the break, and Rad51 promotes strand invasion. • Some events, including mating-type switching in yeast and VDJ recombination involve regulated, specific recombination.
The mechanism of mating-type conversion involves replication to bring about gene conversion.