SUMO-mediated regulation of synaptonemal complex formation during meiosis

摘要

The propagation of most sexually reproducing species is possible due to a specialized form of cell division known as meiosis, which leads to the formation of haploid gametes that fuse upon fertilization, reconstituting the species ploidy. A hallmark of meiosis is the ability to segregate homologous chromosomes away from each other, thereby reducing the chromosome set by half. Mechanistically, this involves pairing, synapsis, and the reciprocal exchange of genetic material (crossover recombination) between homologous chromosomes during prophase I. These events ensure that homologs remain physically connected even after they desynapse, allowing for their proper alignment at the metaphase plate and subsequent segregation to opposite poles of the spindle during the first meiotic division. Failures in ho-molog recognition or in maintaining homologous interactions invariably disrupt meiotic segregation and result in aneuploid gametes. The importance of proper homologous segregation is underscored by the infertility, miscarriages, and various birth defects that trace back to errors in single meiotic events in the paternal or maternal germline progenitors (Hassold and Hunt 2001)