Function of DNA Synthesis Factors in Meiotic Recombination

Meiotic recombination is crucial for normal meiotic chromosome segregation and requires DNA synthesis during the repair of SPO11-mediated double stranded breaks (DSBs). However, the understanding of functions of DNA synthesis factors is limited because of their roles in DNA replication and lethality often caused by mutations affecting their functions. Recently, we have analyzed the important functions of Replication Factor C1 (RFC1) in mediating meiotic crossovers via the ZMM-dependent pathway. Mutations in RFC1 result in abnormal meiosis with multivalents and recombination with reduced interference. We have now characterized other proteins involved in DNA synthesis for their possible functions in meiosis. Our genetic analyses indicate that a gene encoding a putative DNA polymerase is required for normal meiosis and new results from molecular cytogenetic analyses will be presented. In addition, mutations in the DNA polymerase gene also affect meiotic gene expression, and cause defects in meiotic prophase I, including recombination and chromosome segregation. Further analysis is underway and these and other results will be present.