Expression and splice variant analysis of the zebrafish tcf4 transcription factor.
Wnt signalling has been implicated in antero-posterior patterning of the vertebrate embryonic body axis and in a number of other developmental processes. One of the downstream effectors of Wnt signalling is the beta-catenin protein which complexes with members of the Lef/tcf transcription factor family. In the zebrafish, specification of the head has been shown to be dependent on the Tcf3 protein which acts as a repressor of the posteriorizing activity of Wnt (Nature 407 (2000) 913). Here, we report the cloning and expression pattern of the zebrafish tcf4 gene. In embryos, we find that the tcf4 gene is highly regulated at the level of RNA splicing such that the variant proteins that are produced contain or lack domains proposed to be essential in repression or activation of transcription. Expression of tcf4 mRNA is first detected in a graded fashion in the anterior brain and subsequently becomes restricted to the dorsal diencephalon and anterior midbrain. There is also transient expression in the anterior rhombomeres of the hindbrain and in the developing gut.
Millennium Nucleus in Developmental Biology, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile.
Rodrigo M
RM
Young
Ariel E
AE
Reyes
Miguel L
ML
Allende
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019521:Body Patterning / Q000235:genetics; D001921:Brain / Q000196:embryology / Q000378:metabolism; D003001:Cloning, Molecular; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D051820:TCF Transcription Factors; D000073940:Transcription Factor 4; D058118:Transcription Factor 7-Like 2 Protein; D014157:Transcription Factors / Q000235:genetics*; D051153:Wnt Proteins; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000235:genetics*
D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D051820:TCF Transcription Factors; C517154:Tcf4 protein, zebrafish; D000073940:Transcription Factor 4; D058118:Transcription Factor 7-Like 2 Protein; D014157:Transcription Factors; D051153:Wnt Proteins; D029961:Zebrafish Proteins; C094522:wnt8b protein, zebrafish