title: The expression of LIM-homeobox genes, Lhx1 and Lhx5, in the forebrain is essential for neural retina differentiation.
abstract: Elucidating the mechanisms underlying eye development is essential for advancing the medical treatment of eye-related disorders. The primordium of the eye is an optic vesicle (OV), which has a dual potential for generation of the developing neural retina and retinal pigment epithelium. However, the factors that regulate the differentiation of the retinal primordium remain unclear. We have previously shown that overexpression of Lhx1 and Lhx5, members of the LIM-homeobox genes, induced the formation of a second neural retina from the presumptive pigmented retina of the OV. However, the precise timing of Lhx1 expression required for neural retina differentiation has not been clarified. Moreover, RNA interference of Lhx5 has not been previously reported. Here, using a modified electroporation method, we show that, Lhx1 expression in the forebrain around stage 8 is required for neural retina formation. In addition, we have succeeded in the knockdown of Lhx5 expression, resulting in conversion of the neural retina region to a pigment vesicle-like tissue, which indicates that Lhx5 is also required for neural retina differentiation, which correlates temporally with the activity of Lhx1. These results suggest that Lhx1 and Lhx5 in the forebrain regulate neural retina differentiation by suppressing the development of the retinal pigment epithelium, before the formation of the OV.
authors.affiliation: Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama, 700-8558, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Inoue
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Ueda
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Bando
authors.forename: Taro
authors.initials: T
authors.lastname: Mito
authors.forename: Sumihare
authors.initials: S
authors.lastname: Noji
authors.forename: Hideyo
authors.initials: H
authors.lastname: Ohuchi
mesh_terms: D000818:Animals; D030161:Avian Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation / Q000235:genetics; D002642:Chick Embryo; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D060850:LIM-Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D016548:Prosencephalon / Q000196:embryology / Q000378:metabolism*; D034622:RNA Interference; D012160:Retina / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D055748:SOXB1 Transcription Factors / Q000378:metabolism
chemical_list: D030161:Avian Proteins; D060850:LIM-Homeodomain Proteins; D055748:SOXB1 Transcription Factors
keywords: LIM-homeobox; chick; eye development; neural retina; optic vesicle