The Caenorhabditis elegans pvl-5 gene protects hypodermal cells from ced-3-dependent, ced-4-independent cell death.
Programmed cell death (PCD) is regulated by multiple evolutionarily conserved mechanisms to ensure the survival of the cell. Here we describe pvl-5, a gene that likely regulates PCD in Caenorhabditis elegans. In wild-type hermaphrodites at the L2 stage there are 11 Pn.p hypodermal cells in the ventral midline arrayed along the anterior-posterior axis and 6 of these cells become the vulval precursor cells. In pvl-5(ga87) animals there are fewer Pn.p cells (average of 7.0) present at this time. Lineage analysis reveals that the missing Pn.p cells die around the time of the L1 molt in a manner that often resembles the programmed cell deaths that occur normally in C. elegans development. This Pn.p cell death is suppressed by mutations in the caspase gene ced-3 and in the bcl-2 homolog ced-9, suggesting that the Pn.p cells are dying by PCD in pvl-5 mutants. Surprisingly, the Pn.p cell death is not suppressed by loss of ced-4 function. ced-4 (Apaf-1) is required for all previously known apoptotic cell deaths in C. elegans. This suggests that loss of pvl-5 function leads to the activation of a ced-3-dependent, ced-4-independent form of PCD and that pvl-5 may normally function to protect cells from inappropriate activation of the apoptotic pathway.
Joshi
Pradeep
P
Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, 21250, USA.
Eisenmann
David M
DM
D000818:Animals; D017209:Apoptosis; D017173:Caenorhabditis elegans / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics*; D002135:Calcium-Binding Proteins / Q000235:genetics*; D020169:Caspases / Q000235:genetics*; D016923:Cell Death; D003546:Cysteine Endopeptidases / Q000235:genetics*; D017238:Genes, Helminth
D029742:Caenorhabditis elegans Proteins; D002135:Calcium-Binding Proteins; C089224:Ced-4 protein, C elegans; D020169:Caspases; D003546:Cysteine Endopeptidases; C089223:ced-3 protein, C elegans