We describe the identification and characterization of the Saccharomyces cerevisiae ZiP2 gene, which encodes a novel meiosis-specific protein essential for synaptonemal complex formation. In the zip2 mutant, chromosomes are homologously paired but not synapsed. The Zip2 protein localizes to discrete foci on meiotic chromosomes; these foci correspond to sites of convergence between paired homologs that are believed to be sites of synapsis initiation. Localization of Zip2p requires the initiation of meiotic recombination. In a mutant defective in double-strand break repair, Zip2p colocalizes with proteins involved in double-strand break formation and processing. We propose that Zip2p promotes the initiation of chromosome synapsis and that localization of Zip2p to sites of interhomolog recombination ensures synapsis between homologous chromosomes.
Chua, P. R., & Roeder, G. S. (1998). Zip2, a meiosis-specific protein required for the initiation of chromosome synapsis. Cell, 93(3), 349–359. https://doi.org/10.1016/S0092-8674(00)81164-2