Spc25: How the kinetochore protein plays during oocyte meiosis.

摘要

During mammalian female meiosis, the highly specialized cell "oocyte" undergoes a succession of two asymmetric divisions without an intermediate phase of DNA replication, forming a functional gamete capable of being fertilized. However, chromosomal errors for any reason in cell division during this process will result in aneuploidy, a leading cause of reproductive failure and congenital birth defects in humans. An estimated 10-30% of fertilized human eggs have the "wrong" number of chromosomes, with most of these being either trisomic or monosomic. Hence, any insights into the causes and preventions of aneuploidy will be extremely appreciated in the reproductive field. To prevent the missegregation of chromosomes, both mitotic and meiotic cells develop a high-fidelity surveillance system to monitor the coordinated and precise operation of the segregation machinery, which is referred to as the spindle assembly checkpoint, ensuring the accurate chromosome segregation by sensing attachment to microtubules and tension on chromosomes. Although the mechanisms and components regarding kinetochore-microtubule attachment and spindle assembly checkpoint activation have been widely studied and shown highly conserved in mitosis, knowledge in meiosis is limited. In particular, we still do not know much about the conserved differences between mitosis and meiosis or even between the male and female meiosis in the regulation of these biological events.