Pbx1 and Meis1 regulate activity of the Xenopus laevis Zic3 promoter through a highly conserved region.
Xenopus Zic3 (zinc finger in the cerebellum-3) is expressed in the dorsal neural tube of tailbud embryos and tadpoles. We have isolated a 3.1kb DNA fragment from the Xenopus laevis Zic3 locus that drives proper expression of a GFP reporter in transgenic frog tailbud embryos and tadpoles. This fragment contains regions that are highly similar among frogs, mice, and humans. One extremely conserved region contains a predicted Pbx binding site. We found that the transcription factors Pbx1b and Meis1 can bind this site and synergistically transactivate expression of a reporter containing the conserved region. Finally, we found that an intact Pbx site is essential for normal Zic3 promoter activity in transgenic frog embryos. Our data strongly suggest that a highly conserved region of the Zic3 promoter functions by direct interaction with Pbx1b and Meis1.
Kelly
Lisa E
LE
Center for Molecular and Human Genetics, Columbus Children's Research Institute, The Ohio State University, Columbus, OH 43205, USA.
Carrel
Tessa L
TL
Herman
Gail E
GE
El-Hodiri
Heithem M
HM
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D017124:Conserved Sequence; D005786:Gene Expression Regulation / Q000502:physiology; D018398:Homeodomain Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D000075064:Myeloid Ecotropic Viral Integration Site 1 Protein; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D014157:Transcription Factors / Q000235:genetics*; D015533:Transcriptional Activation / Q000235:genetics; D029867:Xenopus Proteins / Q000235:genetics*; D014982:Xenopus laevis / Q000196:embryology* / Q000378:metabolism*
D018398:Homeodomain Proteins; C456284:Meis1b protein, Xenopus; D000075064:Myeloid Ecotropic Viral Integration Site 1 Protein; C456283:PBX1 protein, Xenopus; D014157:Transcription Factors; D029867:Xenopus Proteins; C109036:Zic3 protein, Xenopus