title: Targeting of GFP to newborn rods by Nrl promoter and temporal expression profiling of flow-sorted photoreceptors.
abstract: The Maf-family transcription factor Nrl is a key regulator of photoreceptor differentiation in mammals. Ablation of the Nrl gene in mice leads to functional cones at the expense of rods. We show that a 2.5-kb Nrl promoter segment directs the expression of enhanced GFP specifically to rod photoreceptors and the pineal gland of transgenic mice. GFP is detected shortly after terminal cell division, corresponding to the timing of rod genesis revealed by birthdating studies. In Nrl-/- retinas, the GFP+ photoreceptors express S-opsin, consistent with the transformation of rod precursors into cones. We report the gene profiles of freshly isolated flow-sorted GFP+ photoreceptors from wild-type and Nrl-/- retinas at five distinct developmental stages. Our results provide a framework for establishing gene regulatory networks that lead to mature functional photoreceptors from postmitotic precursors. Differentially expressed rod and cone genes are excellent candidates for retinopathies.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Akimoto
authors.forename: Hong
authors.initials: H
authors.lastname: Cheng
authors.forename: Dongxiao
authors.initials: D
authors.lastname: Zhu
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Brzezinski
authors.forename: Ritu
authors.initials: R
authors.lastname: Khanna
authors.forename: Elena
authors.initials: E
authors.lastname: Filippova
authors.forename: Edwin C T
authors.initials: EC
authors.lastname: Oh
authors.forename: Yuezhou
authors.initials: Y
authors.lastname: Jing
authors.forename: Jose-Luis
authors.initials: JL
authors.lastname: Linares
authors.forename: Matthew
authors.initials: M
authors.lastname: Brooks
authors.forename: Sepideh
authors.initials: S
authors.lastname: Zareparsi
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Mears
authors.forename: Alfred
authors.initials: A
authors.lastname: Hero
authors.forename: Tom
authors.initials: T
authors.lastname: Glaser
authors.forename: Anand
authors.initials: A
authors.lastname: Swaroop
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D050976:Basic-Leucine Zipper Transcription Factors / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism; D002454:Cell Differentiation; D004268:DNA-Binding Proteins / Q000235:genetics; D005136:Eye Proteins / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D020419:Photoreceptor Cells, Vertebrate / Q000166:cytology / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012160:Retina / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D017949:Retinal Cone Photoreceptor Cells / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D017948:Retinal Rod Photoreceptor Cells / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*
chemical_list: D050976:Basic-Leucine Zipper Transcription Factors; D004268:DNA-Binding Proteins; D005136:Eye Proteins; C490037:NRL protein, human; C084884:Nrl protein, mouse; D011994:Recombinant Proteins; D049452:Green Fluorescent Proteins