CELE_C54D1.6, pvl-1, spy-1, C54D1.6

bar-1 encodes a beta-catenin; during C. elegans development, BAR-1 likely functions as a transcriptional coactivator whose activity is required for Q neuroblast migration, P12 cell fate specification, and P3.p through P8.p vulval cell fate specification at two different stages of development; in specifying vulval cell fates, bar-1 interacts with Wnt and MAPK signaling pathways to regulate proper expression of the LIN-39 homeodomain transcription factor, overexpresion of which can partially rescue the bar-1 mutant phenotype; in yeast two-hybrid assays, BAR-1 interacts strongly with the POP-1/TCF transcription factor, and when fused to the Gal4 DNA binding domain, BAR-1 can function in yeast as a transcriptional coactivator; during larval development, BAR-1 expression begins in P3.p through P8.p at the late L1 stage and then disappears from these cells by the mid-L3 stage; BAR-1 is also expressed in P12, in the seam cells, and in cells of the somatic gonad; BAR-1 subcellular localization, assessed using an integrated transgene, reveals localization to the cytoplasm, nucleus, and cell junctions; genetic mosaic analyses indicate that, in P4.p and in P12, bar-1 acts cell autonomously to specify cell fates.

CELE_Y18D10A.5, sgg-1, Y18D10A.5

gsk-3 encodes the C. elegans glycogen synthase kinase ortholog; during embryonic development, GSK-3 functions in the Wnt signaling pathway that restricts specification of mesendodermal tissue to the appropriate blastomere; GSK-3 also functions in a Wnt pathway that regulates anteroposterior axon guidance; GSK-3 plays a role in regulating the oocyte-to-embryo transition, by phosphorylating and negatively regulating the OMA-1 zinc finger protein, and in regulation of the oxidative stress response pathway by phosphorylating SKN-1, thereby excluding it from intestinal nuclei; GSK-3, along with MOM-5/Frizzled and APR-1/APC is also required for distal tip cell migration in the gonad and for the engulfment of apoptotic cells, indicating that the Wnt pathway signals to CED-10/Rac to regulate cytoskeletal rearrangement during different cellular processes; GSK-3 can be phosphorylated by murine ERK2 in vitro, suggesting that it is a substrate for the RTK-RAS-ERK pathway in vivo; consistent with this, GSK-3 phosphorylation is absent in mpk-1 mutant animals.