Purchase this article with an account.
M. P. Feldkaemper, R. Ashby, F. Schaeffel, C. Brand; Identification of Novel ZENK/Egr-1 Transcription Factor Target Genes by Chromatin Immunoprecipitation in the Chicken Retina. Invest. Ophthalmol. Vis. Sci. 2008;49(13):1742.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Recent studies have implicated the transcription factor ZENK (also known as Egr-1) in the feedback mechanisms for visual control of axial eye growth and myopia development. In chicks, ZENK is upregulated in retinal glucagon amacrine cells when axial eye growth is inhibited by positive spectacle lens wear and down-regulated, when it is enhanced by negative spectacle lens wear. We now started to identify novel ZENK/Egr-1 transcription factor target genes in the chicken retina that might be involved in eye growth regulation and the development of myopia.
Chromatin Immunoprecipitation (ChIP) was coupled with nested PCR amplification and subsequent polyacrylamide gel electrophoresis to reduce the number of false positives (ChIP Display, based on the original work of A. Barski and B. Frenkel , Nucleic Acids Res., 2004). The potential Egr-1 binding sites were sequenced and further analyzed by electromobility shift assay (EMSA).
Twenty-nine DNA fragments that may represent the promotor region of new Egr-1 target genes were sequenced. The known mammalian Egr-1 binding site (5’ TTGCG(G/T)GGGCGT 3’) could not be found in any of the precipitated sequences. Three potentially new Egr-1 target genes were identified in the chicken retina: platelet-activating factor acetylhydrolase 1B2 (PAFAH 1B2), a hypothetical protein (LOC769534) and a N-type calcium channel (CACNA 1B). The previously identified target gene PDGF-A was also identified and confirmed.
The identification of Egr-1 target genes in the retina might lead to a better understanding of the signaling cascades and genes that are involved in eye growth regulation and presumably in the development of myopia.
This PDF is available to Subscribers Only