Pax6 Regulation in Retinal Cells by CCCTC Binding Factor

Overview

Journal Invest Ophthalmol Vis Sci

Specialty Ophthalmology

Date 2006 Nov 24

PMID 17122106

Citations 14

Authors

Tie Li

Zhenyu Lu

Luo Lu

Affiliations

Soon will be listed here.

Abstract

Purpose: A previous study demonstrated that CTCF (CCCTC binding factor) regulates homeobox Pax6 gene expression in early embryonic stages and plays a dominant role in eye development. The purpose of the present study was to explore further the mechanism of CTCF controlling Pax6 gene expression in human retinoblastoma (Rb) cells and in the development of chicken and mouse retinas.

Methods: Northern and Western analyses were used to detect expressions of CTCF and Pax6 in Rb cells. Pax6 transcription reporter and deletion mutants were used to study the regulatory interaction between CTCF and Pax6 in Rb cells and in the retina of chicken embryos. CTCF transgenic chicken embryos and mice were established by lipofection and microinjection of linearized cytomegalovirus (CMV)-CTCF construct into fertilized eggs and mouse oocytes, respectively. Injected oocytes were implanted in the uterus of foster mothers through microinjection into the ovarian duct. The expression of CTCF and Pax6 was determined in embryo sections by immunochemistry.

Results: Stimulation of Rb cells with 10% FBS resulted in an increase in CTCF expression and a decrease in Pax6 expression. To study the regulatory mechanism, the Pax6 reporter and its deletion mutant activities were determined in transfected Rb cells and chicken embryonic retinas, revealing that CTCF interacts with the Pax6 gene in Rb cells through transcription control in the 5'-flanking region upstream from the Pax6 P0 promoter. Overexpression of CTCF in Rb cells suppressed Pax6 reporter activity and downregulated endogenous Pax6 expression. In contrast, downregulation of CTCF expression by knockdown of CTCF mRNA using specific small interfering (si)RNA markedly enhanced Pax6 expression in Rb cells. Further study in CTCF transgenic mouse embryos verified that overexpression of CTCF suppressed Pax6 gene expression in the retina.

Conclusions: CTCF plays an important role in regulating Pax6 expression in Rb cells and in the developmental retina, and the regulation of Pax6 gene expression by CTCF in the retina is through transcriptional regulation.

Citing Articles

Building a Mammalian Retina: An Eye on Chromatin Structure.

Daghsni M, Aldiri I Front Genet. 2021; 12:775205.

PMID: 34764989 PMC: 8576187. DOI: 10.3389/fgene.2021.775205.

CTCF-Mediated and Pax6-Associated Gene Expression in Corneal Epithelial Cell-Specific Differentiation.

Tsui S, Wang J, Wang L, Dai W, Lu L PLoS One. 2016; 11(9):e0162071.

PMID: 27583466 PMC: 5008733. DOI: 10.1371/journal.pone.0162071.

Pax6 influences expression patterns of genes involved in neuro- degeneration.

Mishra S, Maurya S, Srivastava K, Shukla S, Mishra R Ann Neurosci. 2015; 22(4):226-31.

PMID: 26525840 PMC: 4627194. DOI: 10.5214/ans.0972.7531.220407.

Transcriptional and epigenetic mechanisms of early cortical development: An examination of how Pax6 coordinates cortical development.

Ypsilanti A, Rubenstein J J Comp Neurol. 2015; 524(3):609-29.

PMID: 26304102 PMC: 4706819. DOI: 10.1002/cne.23866.

Establishing PAX6 as a biomarker to detect early loss of ocular phenotype in human patients with Sjögren's syndrome.

McNamara N, Gallup M, Porco T Invest Ophthalmol Vis Sci. 2014; 55(11):7079-84.

PMID: 25228544 PMC: 4224577. DOI: 10.1167/iovs.14-14828.

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