TheXenopusGATA-4/5/6 Genes Are Associated with Cardiac Specification and Can Regulate Cardiac-Specific Transcription during Embryogenesis

摘要

TheGATAfamilyofnuclearfactorshasbeenimplicatedintheregulationofcelltype-specifictranscription.WereporttheisolationoftheemXenopus/emGATA-4andGATA-6cDNAclonesandcharacterizetheexpressionpatternsofthexGATA-4/5/6genes.BycomparingthesequenceofthecDNAswiththosepreviouslyreportedfromchickandmammaliansources,weconcludethateachisconservedacrossvertebrateevolutionasadistinctgeneproduct.Eachgeneisexpressedindifferentiatedadultheartandgut,butmaintainsdistincttranscriptpatternsinvariousotheradulttissues.Duringembryogenesis,eachgenedisplaysasimilaroverlappingdistributionoftranscriptslocalizedthroughoutthedevelopingcardiogenicregion.ThexGATA-4genecanbedetectedindorsalcardiacprogenitorrudimentspriortomigration.Axisdisruptionexperimentswereusedtodemonstratethattranscriptionofthesegenesisintimatelyassociatedwiththespecificationofcardiacprogenitors.Ectopicexpressionofeachgeneisspecificallycapableofactivatingduringembryogenesisthetranscriptionofthecardiacgenesencodingactinandmyosinheavychainα.ThedataareconsistentwithaprimaryrolefortheGATA-4/5/6genesinregulatingheartdevelopment./p/div