title: Developmental origin of the posterior pigmented epithelium of iris.
abstract: Iris epithelium is a double-layered pigmented cuboidal epithelium. According to the current model, the neural retina and the posterior iris pigment epithelium (IPE) are derived from the inner wall of the optic cup, while the retinal pigment epithelium (RPE) and the anterior IPE are derived from the outer wall of the optic cup during development. Our current study shows evidence, contradicting this model of fetal iris development. We demonstrate that human fetal iris expression patterns of Otx2 and Mitf transcription factors are similar, while the expressions of Otx2 and Sox2 are complementary. Furthermore, IPE and RPE exhibit identical morphologic development during the early embryonic period. Our results suggest that the outer layer of the optic cup forms two layers of the iris epithelium, and the posterior IPE is the inward-curling anterior rim of the outer layer of the optic cup. These findings provide a reasonable explanation of how IPE cells can be used as an appropriate substitute for RPE cells.
authors.affiliation: Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China.
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Wang
authors.forename: Kai
authors.initials: K
authors.lastname: Xiong
authors.forename: Lei
authors.initials: L
authors.lastname: Lu
authors.forename: Dandan
authors.initials: D
authors.lastname: Gu
authors.forename: Songtao
authors.initials: S
authors.lastname: Wang
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Honglei
authors.initials: H
authors.lastname: Xiao
authors.forename: Guomin
authors.initials: G
authors.lastname: Zhou
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D004848:Epithelium / Q000196:embryology / Q000294:innervation / Q000378:metabolism; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D007498:Iris / Q000166:cytology / Q000196:embryology* / Q000294:innervation / Q000378:metabolism; D051379:Mice; D051739:Microphthalmia-Associated Transcription Factor / Q000378:metabolism; D009898:Optic Disk / Q000196:embryology / Q000378:metabolism; D051857:Otx Transcription Factors / Q000378:metabolism; D010858:Pigmentation; D011247:Pregnancy; D021381:Protein Transport; D055748:SOXB1 Transcription Factors / Q000378:metabolism
chemical_list: D051739:Microphthalmia-Associated Transcription Factor; C497659:OTX2 protein, human; D051857:Otx Transcription Factors; C527782:SOX2 protein, human; D055748:SOXB1 Transcription Factors