Abstract
BackgroundIn mitotic cells, WAPL acts as a cohesin release factor to remove cohesin complexes from chromosome arms during prophase to allow the accurate chromosome segregation in anaphase. However, we have recently documented that Wapl exerts a unique meiotic function in the spindle assembly checkpoint (SAC) control through maintaining Bub3 stability during mouse oocyte meiosis I. Whether this noncanonical function is conserved among species is still unknown.MethodsWe applied RNAi-based gene silencing approach to deplete WAPL in porcine oocytes, validating the conserved roles of WAPL in the regulation of SAC activity during mammalian oocyte maturation. We also employed immunostaining, immunoblotting and image quantification analyses to test the WAPL depletion on the meiotic progression, spindle assembly, chromosome alignment and dynamics of SAC protein in porcine oocytes.ResultsWe showed that depletion of WAPL resulted in the accelerated meiotic progression by displaying the precocious polar body extrusion and compromised spindle assembly and chromosome alignment. Notably, we observed that the protein level of BUB3 was substantially reduced in WAPL-depleted oocytes, especially at kinetochores.ConclusionsCollectively, our data demonstrate that WAPL participates in the porcine oocyte meiotic progression through maintenance of BUB3 protein levels and SAC activity. This meiotic function of WAPL in oocytes is highly conserved between pigs and mice.
Highlights
In mitotic cells, WAPL acts as a cohesin release factor to remove cohesin complexes from chromosome arms during prophase to allow the accurate chromosome segregation in anaphase
Localization and expression patterns of WAPL in porcine oocytes We firstly examined the subcellular localization and protein expression patterns of WAPL to predict its specific roles during porcine oocyte meiosis
Upon germinal vesicle breakdown (GVBD), WAPL distributed on the chromosome and concentrated at kinetochores (Fig. 1 a, b) at prometaphase I stage
Summary
WAPL acts as a cohesin release factor to remove cohesin complexes from chromosome arms during prophase to allow the accurate chromosome segregation in anaphase. We have recently documented that Wapl exerts a unique meiotic function in the spindle assembly checkpoint (SAC) control through maintaining Bub stability during mouse oocyte meiosis I. Whether this noncanonical function is conserved among species is still unknown. The spindle assembly checkpoint (SAC), a Chromosome cohesion is another mechanism that is required for faithful chromosome segregation in cells This biological event is mediated by a ring-shaped complex cohesin which consists of four core components: SMC1, SMC3, SCC1 and SCC3 [10,11,12]. We have previously discovered a noncanonical role of Wapl in mediating SAC activity through maintenance of Bub stability during mouse oocyte meiosis I [23]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
