A transcriptional partner for MAD proteins in TGF-beta signalling.
The transforming-growth-factor-beta (TGF-beta) superfamily is critical for establishing mesoderm during early embryogenesis in Xenopus. The transcriptional activation of Mix.2, an immediate-early response gene specific to activin-like members of the TGF-beta superfamily, is associated with the rapid appearance of a site-specific DNA-binding activity that recognizes a fifty-base-pair regulatory element known as ARE in the Mix.2 promoter. Cloning of the site-specific DNA-binding component of this activity revealed it to be a new winged-helix transcription factor and a direct target for signalling by the TGF-beta superfamily. XMAD2, a recently identified TGF-beta signal transducer, forms a complex with the transcription factor in an activin-dependent fashion to generate an activated ARE-binding complex. A model is proposed to explain how TGF-beta superfamily signals might regulate the expression of specific genes in the early embryo.
Chen
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Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Rubock
M J
MJ
Whitman
M
M
D028341:Activins; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000378:metabolism*; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D051858:Forkhead Transcription Factors; D018507:Gene Expression Regulation, Developmental; D007265:Inhibins / Q000378:metabolism; D008969:Molecular Sequence Data; D015398:Signal Transduction; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D014424:Turner Syndrome; D014981:Xenopus; D029867:Xenopus Proteins
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C102067:FOXH1 protein, Xenopus; D051858:Forkhead Transcription Factors; D014157:Transcription Factors; D016212:Transforming Growth Factor beta; D029867:Xenopus Proteins; D028341:Activins; D007265:Inhibins; D004247:DNA