S Ying1, H T Jansen, M N Lehman, S L Fong, W W Kao. 1. Departments of Ophthalmology and Cell Biology, Neurobiology and Anatomy, University of Cincinnati, Cincinnati, OH 45267-0527, USA.
Abstract
PURPOSE: To examine the effect of loss of cone photoreceptor cells on retinal degeneration. METHODS: We previously identified a cone photoreceptor cell-specific promoter of human cone transducin a-subunit (GNAT2) gene. In this report, a minigene, Trc-Tox176, that contains the GNAT2 promoter, an attenuated diphtheria toxin A-chain gene, and an enhancer element from human interphotoreceptor retinoid-binding protein (IRBP) was used to generate coneless transgenic mice. Transgenic mice were identified by PCR and the copy number of the transgene was determined by Southern hybridization, and examined by histology. RESULTS: The results of immunostaining with anti-mouse GNAT2 antibodies and reverse transcription-PCR (RT-PCR) analysis with mRNA from the retinas of transgenic mice showed that cone photoreceptor cells were ablated in one of four transgenic mouse lines. The ablation of cone cells began at postnatal day 8, at the same time as the expression of endogenous GNAT2. An age-related rod degeneration was also found in this cone-ablated mouse line, beginning at postnatal day 9, proceeding from the central retina to the peripheral retina. CONCLUSIONS: Cone photoreceptor cells may play an important role in the survival of rod photoreceptor cells during mouse retina development.
PURPOSE: To examine the effect of loss of cone photoreceptor cells on retinal degeneration. METHODS: We previously identified a cone photoreceptor cell-specific promoter of human cone transducin a-subunit (GNAT2) gene. In this report, a minigene, Trc-Tox176, that contains the GNAT2 promoter, an attenuated diphtheria toxin A-chain gene, and an enhancer element from humaninterphotoreceptor retinoid-binding protein (IRBP) was used to generate coneless transgenic mice. Transgenic mice were identified by PCR and the copy number of the transgene was determined by Southern hybridization, and examined by histology. RESULTS: The results of immunostaining with anti-mouseGNAT2 antibodies and reverse transcription-PCR (RT-PCR) analysis with mRNA from the retinas of transgenic mice showed that cone photoreceptor cells were ablated in one of four transgenicmouse lines. The ablation of cone cells began at postnatal day 8, at the same time as the expression of endogenous GNAT2. An age-related rod degeneration was also found in this cone-ablated mouse line, beginning at postnatal day 9, proceeding from the central retina to the peripheral retina. CONCLUSIONS: Cone photoreceptor cells may play an important role in the survival of rod photoreceptor cells during mouse retina development.
Authors: Frank M Dyka; Sanford L Boye; Renee C Ryals; Vince A Chiodo; Shannon E Boye; William W Hauswirth Journal: Adv Exp Med Biol Date: 2014 Impact factor: 2.622