title: Transgenic analysis of the anterior eye-specific enhancers of the zebrafish gelsolin-like 1 (gsnl1) gene.
abstract: The anterior segment of the eye includes such structures as the cornea, lens, iris, and ciliary body and is essential for many visual and physiological functions of the eye. The zebrafish gelsolin-like 1 (gsnl1) gene encodes an actin regulatory protein and is expressed in the anterior segment of the eye. We report the transgenic analyses of the gsnl1 promoter and enhancer that are required for expression in the anterior segment of the eye. A 6.4-kb genomic fragment upstream from the translation initiation site (ATG) was capable of driving green fluorescent protein (GFP) expression in transient transgenic embryos and stable transgenic adult fish, which mimics the endogenous gsnl1 expression. The GFP expression was localized in the corneal epithelium (CE) and the annular ligament (AL) at the iridocorneal angle. A unique enhancer for each of these two tissues was identified at 3.7-kb upstream from the ATG. The 60-bp AL and 25-bp CE enhancers were separated by 100-bp and functioned independently from each other. Deletion analysis indicated that the proximal promoter was located 1.6-kb upstream from the ATG. Stable GFP transgenic lines were established for future studies of genetic regulation in the anterior segment of the fish eye.
authors.affiliation: Department of Ophthalmology and Visual Science and the Hermann Eye Center, University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.
authors.forename: Shunichi
authors.initials: S
authors.lastname: Yoshikawa
authors.forename: Evan
authors.initials: E
authors.lastname: Norcom
authors.forename: Hisashi
authors.initials: H
authors.lastname: Nakamura
authors.forename: Richard W
authors.initials: RW
authors.lastname: Yee
authors.forename: Xinping C
authors.initials: XC
authors.lastname: Zhao
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D000869:Anterior Eye Segment / Q000378:metabolism*; D004742:Enhancer Elements, Genetic; D018260:Gelsolin / Q000235:genetics*; D011401:Promoter Regions, Genetic; D015027:Zebrafish / Q000235:genetics* / Q000378:metabolism
chemical_list: D018260:Gelsolin