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The role of ubiquitin ligase APC/C in regulating the meiotic cell cycle
The meiotic cell cycle is unique in that it involves two M phases with no intervening S phase. A peculiar characteristic of female meiosis in vertebrates is that oocytes undergo distinct cell cycle arrests: immature oocytes arrest at prophase at meiosis I and following meiotic maturation they arrest as mature oocytes again at metaphase of meiosis II.
The prophase I arrest of immature oocytes – which belongs to the longest known cell cycle arrests – is released by hormonal stimulation, while the MII arrest of mature oocytes is released by fertilization.
Our research aims at a better understanding of how the interplay of reversible protein phosphorylation and selective destruction by the ubiquitin-proteasome pathway controls the MI and MII arrest of oocytes and the release of oocytes from these arrest stages.