Ontogenetic expression of the Otx2 and Crx homeobox genes in the retina of the rat

TY - JOUR

T1 - Ontogenetic expression of the Otx2 and Crx homeobox genes in the retina of the rat

AU - Rath, Martin F

AU - Morin, Fabrice

AU - Shi, Qiong

AU - Klein, David C

AU - Møller, Morten

N1 - Paper id:: PMID: 17467693

PY - 2007/7/1

Y1 - 2007/7/1

N2 - Otx2 and Crx are vertebrate orthologs of the orthodenticle family of homeobox genes, which are involved in retinal development. In this study, the temporal expression patterns of Otx2 and Crx in the rat retina during embryonic and postnatal stages of development were analyzed in detail. This confirmed the presence of Otx2 mRNA in both the embryonic retinal pigment epithelium and the developing neural retina. During development, the expression of Otx2 persists in the pigment epithelium, whereas Otx2 expression of the neural retina becomes progressively restricted to the outer nuclear layer and the outer part of the inner nuclear layer. Immunohistochemistry revealed that Otx2 protein is also present in cell bodies of the ganglion cell layer, which does not contain the Otx2 transcript, suggesting that Otx2 protein is synthesized in cell bodies of the bipolar neurons and then transported to and taken up by cells in the ganglion cell layer. Crx is also highly expressed in the outer nuclear layer starting at E17 and postnatally in the inner nuclear layer. The onset of expression of Crx lags behind that of Otx2 consistent with evidence that Otx2 activates Crx transcription. These expression patterns are consistent with evidence that Otx2 and Crx function during retinal development and extend the period of probable functionality to the adult. In this regard, these results provide an enhanced and expanded temporal and spatial framework for understanding the multiple roles of Otx2 and Crx in the developing and mature mammalian retina.

AB - Otx2 and Crx are vertebrate orthologs of the orthodenticle family of homeobox genes, which are involved in retinal development. In this study, the temporal expression patterns of Otx2 and Crx in the rat retina during embryonic and postnatal stages of development were analyzed in detail. This confirmed the presence of Otx2 mRNA in both the embryonic retinal pigment epithelium and the developing neural retina. During development, the expression of Otx2 persists in the pigment epithelium, whereas Otx2 expression of the neural retina becomes progressively restricted to the outer nuclear layer and the outer part of the inner nuclear layer. Immunohistochemistry revealed that Otx2 protein is also present in cell bodies of the ganglion cell layer, which does not contain the Otx2 transcript, suggesting that Otx2 protein is synthesized in cell bodies of the bipolar neurons and then transported to and taken up by cells in the ganglion cell layer. Crx is also highly expressed in the outer nuclear layer starting at E17 and postnatally in the inner nuclear layer. The onset of expression of Crx lags behind that of Otx2 consistent with evidence that Otx2 activates Crx transcription. These expression patterns are consistent with evidence that Otx2 and Crx function during retinal development and extend the period of probable functionality to the adult. In this regard, these results provide an enhanced and expanded temporal and spatial framework for understanding the multiple roles of Otx2 and Crx in the developing and mature mammalian retina.

KW - Animals

KW - Blotting, Western

KW - Densitometry

KW - Eye Proteins

KW - Gene Expression Regulation, Developmental

KW - Genes, Homeobox

KW - Homeodomain Proteins

KW - Hypothalamus

KW - Immunohistochemistry

KW - In Situ Hybridization

KW - Neurons

KW - Otx Transcription Factors

KW - Pigment Epithelium of Eye

KW - RNA, Messenger

KW - Rats

KW - Rats, Sprague-Dawley

KW - Retina

KW - Retinal Ganglion Cells

KW - Trans-Activators

KW - Transcription, Genetic

U2 - 10.1016/j.exer.2007.02.016

DO - 10.1016/j.exer.2007.02.016

M3 - Journal article

C2 - 17467693

SN - 0014-4835

VL - 85

SP - 65

EP - 73

JO - Experimental Eye Research

JF - Experimental Eye Research

IS - 1

ER -