Evidence that POU factor Brn-3B regulates expression of Pax-6 in neuroretina cells.
The Pax-6 gene encodes a transcriptional master regulator involved in the development of the eye. The quail Pax-6 gene is expressed in the neuroretina from two promoters, P0 and P1, and is regulated by an intragenic neuroretina-specific enhancer (EP enhancer). The activity of this enhancer is restricted to the P0 promoter, which is activated at the onset of neuronal differentiation. In this article, we show that the POU domain transcription factor Brn-3b, which is expressed in various regions of the brain including retina and sensory neurons, is one of the factors interacting with the EP enhancer. Brn-3b strongly activates the EP enhancer in neuroretina cells but not in other cell types. Interestingly, this activation appears to be specific for Brn-3b, as the closely related POU factors Brn-3a and Brn-3c do not show activation of the EP enhancer. Our results identify the Pax-6 gene as a new potential downstream effector of the POU transcription factor Brn-3b.
Plaza
S
S
CNRS EP 560/Institut Pasteur, Institut de Biologie, 1 Rue Calmette, BP 447, 59021 Lille Cedex, France.
Hennemann
H
H
Möröy
T
T
Saule
S
S
Dozier
C
C
D000818:Animals; D015153:Blotting, Western; D002478:Cells, Cultured; D002642:Chick Embryo; D004268:DNA-Binding Proteins / Q000235:genetics*; D004586:Electrophoresis; D004742:Enhancer Elements, Genetic / Q000502:physiology; D005136:Eye Proteins; D005786:Gene Expression Regulation / Q000502:physiology; D018398:Homeodomain Proteins; D009474:Neurons / Q000737:chemistry* / Q000502:physiology; D000071841:PAX6 Transcription Factor; D050809:POU Domain Factors; D051761:Paired Box Transcription Factors; D011784:Quail; D012097:Repressor Proteins; D012160:Retina / Q000737:chemistry* / Q000166:cytology / Q000502:physiology; D050818:Transcription Factor Brn-3; D050820:Transcription Factor Brn-3B; D050821:Transcription Factor Brn-3C; D014157:Transcription Factors / Q000235:genetics*
D004268:DNA-Binding Proteins; D005136:Eye Proteins; D018398:Homeodomain Proteins; D000071841:PAX6 Transcription Factor; D050809:POU Domain Factors; D051761:Paired Box Transcription Factors; D012097:Repressor Proteins; D050818:Transcription Factor Brn-3; D050820:Transcription Factor Brn-3B; D050821:Transcription Factor Brn-3C; D014157:Transcription Factors