The ubiquitin ligase CRL2ZYG11 targets cyclin B1 for degradation in a conserved pathway that facilitates mitotic slippage.

The anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase is known to target the degradation of cyclin B1, which is crucial for mitotic progression in animal cells. In this study, we show that the ubiquitin ligase CRL2 redundantly targets the degradation of cyclin B1 in Caenorhabditis elegans and human cells. In C.

The Caenorhabditis elegans cell-cycle regulator ZYG-11 defines a conserved family of CUL-2 complex components.

The cullin CUL-2 is a crucial component of a subclass of multisubunit cullin-RING ubiquitin-ligases. The specificity of CUL-2-based complexes is provided by variable substrate-recognition subunits that bind to specific substrates. In Caenorhabditis elegans, CUL-2 regulates several key processes in cell division and embryonic development, including meiotic progression, anterior-posterior polarity and mitotic chromatin condensation.

CUL-2 and ZYG-11 promote meiotic anaphase II and the proper placement of the anterior-posterior axis in C. elegans.

The faithful segregation of chromosomes during meiosis is vital for sexual reproduction. Currently, little is known about the molecular mechanisms regulating the initiation and completion of meiotic anaphase. We show that inactivation of CUL-2, a member of the cullin family of ubiquitin ligases, delays or abolishes meiotic anaphase II with no effect on anaphase I, indicating differential regulation during the two meiotic stages.