Inhibitory Patterning of the Anterior Neural Plate in Xenopus by Homeodomain Factors Dlx3 and Msx1

摘要

Patterningoftheembryonicectodermisdependentupontheactionofnegative(antineural)andpositive(neurogenic)transcriptionalregulators.Msx1andDlx3aretwoantineuralgenesforwhichtheanteriorepidermalndash;neuralboundariesofexpressiondiffer,probablyduetodifferentialsensitivitytoBMPsignalingintheectoderm.Intheextremeanteriorneuralplate,Dlx3isstronglyexpressedwhileMsx1issilent.Whilebothofthesefactorspreventtheactivationofgenesspecifictothenascentcentralnervoussystem,Msx1inhibitsanteriormarkers,includingOtx2andcementgland-specificgenes.Dlx3haslittle,ifany,effectontheseanteriorneuralplategenes,insteadprovidingapermissiveenvironmentfortheirexpressionwhilerepressingmorepanneuralmarkers,includingprepatterngenesbelongingtotheZicfamilyandBF-1.Thesepropertiesdefineamolecularmechanismfortranslatingtheorganizer-dependentmorphogenicgradientofBMPactivityintospatiallyrestrictedgeneexpressionintheprospectiveanteriorneuralplate./p/div