sem-4 Promotes Vulval Cell-Fate Determination in Caenorhabditis elegans through Regulation of lin-39 Hox

摘要

Vulvalcell-fatedeterminationinemCaenorhabditiselegans/emrequirestheactionofnumerousgeneproducts,includingcomponentsoftheRas/Raf/MAPKsignalingcascadeandthehoxgeneemlin-39.sem-4/emencodesazincfingerproteinwithpreviouslycharacterizedrolesinfatespecificationofsexmyoblasts,coelomocytes,andmultipleneuronallineagesinemC.elegans/em(M.BassonandR.Horvitz,1996,emGenesDev./em10,1953ndash;1965).Bycharacterizingthreenewallelesofemsem-4/emthatweidentifiedinascreenforvulval-defectivemutants,wedeterminedthatlossofemsem-4/emactivityresultsinabnormalspecificationofthesecondaryvulvalcelllineages.Weanalyzedemsem-4/eminteractionswithothergenesinvolvedinvulvaldifferentiationanddeterminedthatemsem-4/emdoesnotfunctiondirectlyintheRas-mediatedsignaltransductionpathwaybutactsincloseassociationwithandupstreamofemlin-39/emtopromotevulvalcellfate.Wedemonstratethatemsem-4/emregulatesemlin-39/emexpressionandproposethatemsem-4/emisaregulatorofemlin-39/eminthevulvalcell-fatedeterminationpathwaythatmayacttolinkemlin-39/emtoincomingsignals./p/div