Degrade to create: developmental requirements for ubiquitin-mediated proteolysis during early C. elegans embryogenesis.

The ubiquitin protein conjugation system tags proteins with the small polypeptide ubiquitin. Most poly-ubiquitinated proteins are recognized and degraded by the proteasome, a large multi-subunit protease. Ubiquitin-dependent protein degradation is used as a regulatory tool for many essential processes, the best studied of which is eukaryotic cell cycle progression. More recently, genetic studies in C. elegans have identified multiple roles for the ubiquitin system in early development, where ubiquitin-dependent protein degradation governs such diverse events as passage through meiosis, cytoskeletal regulation and cell fate determination.