A PP2A regulatory subunit positively regulates Ras-mediated signaling during Caenorhabditis elegans vulval induction

Open Access
Publisher Website
Google Scholar
Abstract
We describe evidence that a regulatory B subunit of protein phosphatase 2A (PP2A) positively regulates an RTK–Ras–MAP kinase signaling cascade during Caenorhabditis elegans vulval induction. Although reduction of sur-6 PP2A-B function causes few vulval induction defects in an otherwise wild-type background,sur-6 PP2A-B mutations suppress the Multivulva phenotype of an activated ras mutation and enhance the Vulvaless phenotype of mutations in lin-45 raf, sur-8, or mpk-1. Double mutant analysis suggests that sur-6 PP2A-B acts downstream or in parallel to ras, but likely upstream ofraf, and functions with ksr-1 in a common pathway to positively regulate Ras signaling.