Caenorhabditis elegans p53: Role in apoptosis, meiosis, and stress resistance

We have identified a homolog of the mammalian p53 tumor suppressor protein in the nematode Caenorhabditis elegans that is expressed ubiquitously in em bryos. The gene encoding this protein, cep-1, promotes DNA damage-induced a poptosis and is required for normal meiotic chromosome segregation in the g erm line. Moreover, although somatic apoptosis is unaffected, cep-1 mutants show hypersensitivity to hypoxia-induced lethality and decreased longevity in response to starvation-induced stress. Overexpression of cep-1 promotes widespread caspase-independent cell death, demonstrating the critical impo rtance of regulating p53 function at appropriate levels. These findings sho w that C. elegans p53 mediates multiple stress responses in the soma, and m ediates apoptosis and meiotic chromosome segregation in the germ line.