title: CRISPR-engineered mosaicism rapidly reveals that loss of Kcnj13 function in mice mimics human disease phenotypes.
abstract: The era of genomics has demanded the development of more efficient and timesaving approaches to validate gene function in disease. Here, we utilized the CRISPR-Cas9 system to generate Kcnj13 mutant mice by zygote injection to verify the pathogenic role of human KCNJ13, mutations of which are thought to cause Leber congenital amaurosis (LCA), an early-onset form of blindness. We found that complete loss of Kcnj13 is likely postnatal lethal. Among surviving F0-generation mice examined, 80% show mosaic KCNJ13 expression in the retinal pigment epithelium (RPE). Mosaic expression correlates with decreased response to light and photoreceptor degeneration, indicating that Kcnj13 mutant mice mimic human KCNJ13-related LCA disease. Importantly, mosaic animals enable us to directly compare Kcnj13 mutant and wild-type RPE cells in the same eye. We found that RPE cells lacking KCNJ13 protein still survive but overlying photoreceptors exhibit cell degeneration. At the same time, wild-type RPE cells can rescue neighboring photoreceptor cells that overlie mutant RPE cells. These results suggest that KCNJ13 expression is required for RPE cells to maintain photoreceptor survival. Moreover, we show that CRISPR-Cas9 engineered mosaicism can be used to rapidly test candidate gene function in vivo.
authors: Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030.
authors: Hua
authors: H
authors: Zhong
authors: 1] HGSC, Baylor College of Medicine, Houston, TX 77030 [2] Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030.
authors: Yiyun
authors: Y
authors: Chen
authors: 1] HGSC, Baylor College of Medicine, Houston, TX 77030 [2] Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030.
authors: Yumei
authors: Y
authors: Li
authors: 1] HGSC, Baylor College of Medicine, Houston, TX 77030 [2] Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030 [3] Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030.
authors: Rui
authors: R
authors: Chen
authors: 1] Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030 [2] Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030 [3] Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030 [4] Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030 [5] Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030.
authors: Graeme
authors: G
authors: Mardon
mesh_terms: D000818:Animals; D064113:CRISPR-Cas Systems; D006801:Humans; D057130:Leber Congenital Amaurosis / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D009030:Mosaicism; D024661:Potassium Channels, Inwardly Rectifying / Q000235:genetics / Q000378:metabolism; D055213:Retinal Pigment Epithelium / Q000378:metabolism*
chemical_list: C489477:Kir7.1 channel; D024661:Potassium Channels, Inwardly Rectifying