Multiple regulatory elements with spatially and temporally distinct activities control the expression of the epithelial differentiation gene lin-26 in C. elegans

摘要

Epithelialdifferentiationisaveryearlyeventduringdevelopmentofmostspecies.ThenematodeemCaenorhabditiselegans/em,withitswell-definedandinvariantlineage,offersthepossibilitytolinkcelllineage,cellfatespecificationandgeneregulationduringepithelialdifferentiation.Here,wefocusontheregulationofthegeneemlin-26/em,whichisrequiredforproperdifferentiationofepithelialcellsintheectodermandmesoderm(somaticgonad).emlin-26/emexpressionstartsinearlyembryosandremainsonthroughoutdevelopment,inmanycelltypesoriginatingfromdifferentsublineages.UsingGFPreportersandmutantrescueassays,weperformedamoleculardissectionoftheemlin-26/empromoterandcouldidentifyalmostallelementsrequiredtoestablishitscomplexspatialandtemporalexpression.Mostoftheseelementsactredundantly,orsynergisticallyoncecombined,todriveexpressionincellsrelatedbyfunction.Wealsoshowthatemlin-26/empromoterelementsmediateactivationintheepidermis(hypodermis)bytheGATAfactorELT-1,orrepressionintheforegut(pharynx)bytheFoxAproteinPHA-4.Takentogether,ourdataindicatethatemlin-26/emregulationisachievedtoalargeextentthroughtissue-specificemcis/em-regulatoryelements./p/div