{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T12:55:47Z","timestamp":1788353747553,"version":"build-2803163510"},"reference-count":36,"publisher":"Oxford University Press (OUP)","issue":"7","license":[{"start":{"date-parts":[[2021,10,15]],"date-time":"2021-10-15T00:00:00Z","timestamp":1634256000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"DOI":"10.13039\/100000053","name":"National Eye Institute","doi-asserted-by":"publisher","award":["R01 EY020542"],"award-info":[{"award-number":["R01 EY020542"]}],"id":[{"id":"10.13039\/100000053","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000053","name":"National Eye Institute","doi-asserted-by":"publisher","award":["R01s EY027387"],"award-info":[{"award-number":["R01s EY027387"]}],"id":[{"id":"10.13039\/100000053","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000053","name":"National Eye Institute","doi-asserted-by":"publisher","award":["EY030912"],"award-info":[{"award-number":["EY030912"]}],"id":[{"id":"10.13039\/100000053","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000053","name":"National Eye Institute","doi-asserted-by":"publisher","award":["R01 EY026216"],"award-info":[{"award-number":["R01 EY026216"]}],"id":[{"id":"10.13039\/100000053","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,3,31]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Heteromeric Kv2.1\/Kv8.2 channels are voltage-gated potassium channels localized to the photoreceptor inner segment. They carry IKx, which is largely responsible for setting the photoreceptor resting membrane potential. Mutations in Kv8.2 result in childhood-onset cone dystrophy with supernormal rod response (CDSRR). We generated a Kv8.2 knockout (KO) mouse and examined retinal signaling and photoreceptor degeneration to gain deeper insight into the complex phenotypes of this disease. Using electroretinograms, we show that there were delayed or reduced signaling from rods depending on the intensity of the light stimulus, consistent with reduced capacity for light-evoked changes in membrane potential. The delayed response was not seen ex vivo where extracellular potassium levels were controlled by the perfusion buffer, so we propose the in vivo alteration is influenced by genotype-associated ionic imbalance. We observed mild retinal degeneration. Signaling from cones was reduced but there was no loss of cone density. Loss of Kv8.2 altered responses to flickering light with responses attenuated at high frequencies and altered in shape at low frequencies. The Kv8.2 KO line on an all-cone retina background had reduced cone-driven ERG b wave amplitudes and underwent degeneration. Altogether, we provide insight into how a deficit in the dark current affects the health and function of photoreceptors.<\/jats:p>","DOI":"10.1093\/hmg\/ddab301","type":"journal-article","created":{"date-parts":[[2021,10,12]],"date-time":"2021-10-12T17:28:02Z","timestamp":1634059682000},"page":"1035-1050","source":"Crossref","is-referenced-by-count":21,"title":["Differential impact of Kv8.2 loss on rod and cone signaling and degeneration"],"prefix":"10.1093","volume":"31","author":[{"given":"Shivangi M","family":"Inamdar","sequence":"first","affiliation":[{"name":"Department of Biochemistry and Molecular Biology, University of Iowa, Iowa, IA 52252, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Colten K","family":"Lankford","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Molecular Biology, University of Iowa, Iowa, IA 52252, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deepak","family":"Poria","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology and Visual Sciences, Washington University, St. Louis, MO 63110, USA"},{"name":"Gavin Herbert Eye Institute, School of Medicine, Irvine, CA 92697, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joseph G","family":"Laird","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Molecular Biology, University of Iowa, Iowa, IA 52252, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eduardo","family":"Solessio","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology and Visual Sciences, Center for Vision Research, SUNY Upstate Medical University, Syracuse, NY 13210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vladimir J","family":"Kefalov","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology and Visual Sciences, Washington University, St. Louis, MO 63110, USA"},{"name":"Gavin Herbert Eye Institute, School of Medicine, Irvine, CA 92697, USA"},{"name":"Department of Physiology and Biophysics, University of California, Irvine, CA 92697, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0259-0652","authenticated-orcid":false,"given":"Sheila A","family":"Baker","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Molecular Biology, University of Iowa, Iowa, IA 52252, USA"},{"name":"Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa, IA 52252, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2021,10,15]]},"reference":[{"key":"2022040211520967600_ref1","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1085\/jgp.201511507","article-title":"Kv5, Kv6, Kv8, and Kv9 subunits: no simple silent bystanders","volume":"147","author":"Bocksteins","year":"2016","journal-title":"J. Gen. Physiol."},{"key":"2022040211520967600_ref2","doi-asserted-by":"crossref","first-page":"718","DOI":"10.1001\/archopht.1983.01040010718003","article-title":"Cone dystrophy, nyctalopia, and supernormal rod responses. A new retinal degeneration","volume":"101","author":"Gouras","year":"1983","journal-title":"Arch. Ophthalmol."},{"key":"2022040211520967600_ref3","doi-asserted-by":"crossref","first-page":"574","DOI":"10.1086\/507568","article-title":"Mutations in the gene KCNV2 encoding a voltage-gated potassium channel subunit cause \"cone dystrophy with supernormal rod electroretinogram\" in humans","volume":"79","author":"Wu","year":"2006","journal-title":"Am. J. Hum. Genet."},{"key":"2022040211520967600_ref4","doi-asserted-by":"crossref","first-page":"208","DOI":"10.1080\/13816810.2020.1766087","article-title":"KCNV2 retinopathy: clinical features, molecular genetics and directions for future therapy","volume":"41","author":"Guimaraes","year":"2020","journal-title":"Ophthalmic Genet."},{"key":"2022040211520967600_ref5","doi-asserted-by":"crossref","first-page":"332","DOI":"10.1136\/bjo.2004.050567","article-title":"A detailed phenotypic study of \"cone dystrophy with supernormal rod ERG\"","volume":"89","author":"Michaelides","year":"2005","journal-title":"Br. J. Ophthalmol."},{"key":"2022040211520967600_ref6","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1097\/IAE.0b013e3181bfe24e","article-title":"``Cone dystrophy with supernormal rod electroretinogram'': a comprehensive genotype\/phenotype study including fundus autofluorescence and extensive electrophysiology","volume":"30","author":"Robson","year":"2010","journal-title":"Retina"},{"key":"2022040211520967600_ref7","doi-asserted-by":"crossref","first-page":"898","DOI":"10.1167\/iovs.12-10971","article-title":"Phenotypic characteristics including in vivo cone photoreceptor mosaic in KCNV2-related ``cone dystrophy with supernormal rod electroretinogram''","volume":"54","author":"Vincent","year":"2013","journal-title":"Invest. Ophthalmol. Vis. 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