Cell death specification in C. elegans.

Years of research have identified a highly conserved mechanism required for apoptotic cell killing. How certain cells are specified to die is not well understood. With a rich history in programmed cell death research, the nematode C. elegans offers an excellent animal model with which to study cell death specification events. Developing hermaphrodites have 131 invariant cell death events that can be studied with single cell resolution. Recent genetic studies have begun to identify diverse sets of factors required for the proper specification of individual cell death events. The limited findings thus far suggest that cell death specification is controlled through transcriptional regulation of at least two members of the core cell death pathway, egl-1 and ced-3. However, it remains unclear if additional modes of cell death specification exist. Here we briefly summarize current findings in the field of C. elegans cell death specification and consider those questions that remain to be answered.