BIOL 039 Lecture Notes - Lecture 22: Rad51, Meiosis, Chromosome
Document Summary
The most important features distinguishing the holliday model and current models are that. It is now known that meiotic recombination is initiated by double-stranded breaks in dna, and. Double-stranded breaks that initiate recombination are not spontaneous, but are generated in a prog-rammed manner by the activity of special enzymes. The current model for the dna recombination mechanism. Was proposed by szostak, orr-weaver, rothstein, and stahl (1983) Recombination is initiated by the protein spo11, discovered in yeast. It generates an double-stranded cut in one chromatid, and then the proteins. Mrx resects the single strands of the cut chromatid. The proteins rad51 and dmc1 (proteins that also perform the dsb repair) facilitate strand invasion. Strand invasion creates the first holliday junction, a d loop and the first heteroduplex region. The heteroduplex is double-stranded dna formed from dna of different homologs. The invading strand is extended, with dna synthesis guided by the intact template strands.
