title: Pbx1 and Meis1 regulate activity of the Xenopus laevis Zic3 promoter through a highly conserved region.
abstract: 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.
authors.affiliation: Center for Molecular and Human Genetics, Columbus Children's Research Institute, The Ohio State University, Columbus, OH 43205, USA.
authors.forename: Lisa E
authors.initials: LE
authors.lastname: Kelly
authors.forename: Tessa L
authors.initials: TL
authors.lastname: Carrel
authors.forename: Gail E
authors.initials: GE
authors.lastname: Herman
authors.forename: Heithem M
authors.initials: HM
authors.lastname: El-Hodiri
mesh_terms: 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*
chemical_list: 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