Misexpression of cNSCL1 disrupts retinal development.
cNSCL1 is the chick homologue of mammalian NSCL1, a basic helix-loop-helix gene transiently expressed during neurogenesis. To gain insight into its function, we studied the involvement of cNSCL1 in retinal neurogenesis. In situ hybridization showed dynamic, cell-type-specific expression of cNSCL1, first in developing ganglion cells and later in glial cells. This is drastically different from the expression of neuroD in young photoreceptor cells and their precursors, demonstrating that the proposed neurogenin --> neuroD --> NSCL1 cascade might not apply to retinal neurogenesis in the chick. Small eyes were produced when cNSCL1 was misexpressed in the retinal neuroepithelium through viral transduction. Pulse-labeling with BrdU and [(3)H]thymidine revealed a significant decrease in cell proliferation activity with cNSCL1 misexpression. Massive cell death occurred, but only after cell proliferation activity had subsided, resulting in major distortions of retinal structure. Our data demonstrate the importance of regulated expression of cNSCL1 during retinal development.
Li
C M
CM
Department of Ophthalmology, University of Alabama at Birmingham School of Medicine, Birmingham, Alabama 35233, USA.
Yan
R T
RT
Wang
S Z
SZ
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D002642:Chick Embryo; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000502:physiology; D004848:Epithelium / Q000196:embryology; D018507:Gene Expression Regulation, Developmental; D018257:Helix-Loop-Helix Motifs; D009024:Morphogenesis; D009419:Nerve Tissue Proteins / Q000235:genetics; D009457:Neuroglia / Q000166:cytology / Q000502:physiology*; D020419:Photoreceptor Cells, Vertebrate / Q000502:physiology; D011994:Recombinant Proteins / Q000096:biosynthesis; D012160:Retina / Q000002:abnormalities* / Q000166:cytology / Q000196:embryology*; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000502:physiology*; D012190:Retroviridae / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection; D029867:Xenopus Proteins
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; D029867:Xenopus Proteins; C101907:neurogenin, Xenopus; C093564:Neurogenic differentiation factor 1