Identification of joint molecules that form frequently between homologs but rarely between sister chromatids during yeast meiosis

摘要: We have investigated DNA interactions between homologs and sister chromatids during meiosis in S. cerevisiae. detected a species containing information from both parental chromosomes at specific hotspot for meiotic recombination double strand breaks (DSBs). These joint molecules are prominent feature of prophase. They appear to be major intermediate stage DSB-promoted recombination, because they occur with appropriate timing require known functions. Other possibilities cannot completely dismissed, however. Most or all contain two full-length nonrecombinant strands each duplex thus do not consist single Holliday junctions. Joint form approximately 10% the interhomolog level. Also, molecule formation is aberrant mutant defective HOP1 gene, which encodes chromosome structure component. General models discrimination sisters discussed.