Cellular basis of ClC-2 Cl? channel–related brain and testis pathologies

The ClC-2 chloride channel is expressed in the plasma membrane of almost all mammalian cells. Mutations that cause loss function lead to retinal and testicular degeneration leukodystrophy, whereas gain-of-function mutations hyperaldosteronism. Leukodystrophy also observed with a GlialCAM, cell adhesion molecule binds glia. GlialCAM changes localization opens by altering its gating. We now used type–specific deletion mice show depend on pigment epithelial cells Sertoli cells, respectively, leukodystrophy was fully developed only when disrupted both astrocytes oligodendrocytes. Glialcam?/? could not be rescued crosses Clcn2op/op which mutation mimics “opening” GlialCAM. These data indicate GlialCAM-induced biophysical properties are irrelevant for GLIALCAM-related leukodystrophy. Taken together, our findings suggest pathology caused Clcn2 disruption results from disturbed extracellular ion homeostasis identifies involved this process. Chloride channels molecularly very diverse. 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Fernandes-Rosa Pathogenesis hypertension mouse model hyperaldosteronism.Nat. 10: 4678Crossref (19) knockin (Clcn2op/op) N-terminal deletion, based previous structure-function similar degree aldosteronism-associated (28Göppner Adrenal zona glomerulosa strongly depolarized currents, resulting increased Ca2+-influx stimulation aldosterone synthesis explore effects markedly tissues. better understand mechanisms underlying ClC-2-related disease, models genetically identify types critically pathogenesis. Targeted those responsible respectively. Specific oligodendrocytes produced no mild full extent Clcn2-related combined types. Finally, mice, showing plays significant mice. Our work bolsters notion crucial various tissues regulation. Conditional Clcn2lox/lox homologous recombination embryonic stem Exons 2 3 flanked loxP sites (Fig. S1, B). Excision exons Cre recombinase expected frameshift termination codon occurs before transmembrane domain. Western blots brain lysates normal amounts S1C). When crossed deleter express Cre-recombinase (29Schwenk Baron Rajewsky cre-transgenic strain ubiquitous loxP-flanked segments including cells.Nucleic Acids Res. 1995; 23: 5080-5081Crossref (995) lost detectable immunoreactivity just like After validation, lines causally infertile owing ensuing azoospermia Infertility has found patient In seminiferous tubules fail lumina do complete meiosis. Eventually, stages lost, cell–only phenotype Based immunohistochemical detection their morphology hypothesized normally provide vital support Considering nearly pattern ClC-2, possibilities excluded, however. AMH-Cre (30Lécureuil Fontaine Crepieux Guillou granulosa cell-specific activity transgenic mice.Genesis. 33: 114-118Crossref (176) create cell–specific (named SC-?C2 mice), Stra8-Cre (31Sadate-Ngatchou P.I. Payne C.J. Dearth A.T. Braun R.E. specific postnatal, premeiotic 2008; 46: 738-742Crossref (198) generate GC-?C2 blot proteins whole somewhat more reduced than 1A, Fig. S2A). apparent discrepancy immunofluorescence, detects Sertoli, 1B), might explained easily detectable, patchy Confirming Clcn2, ClC-2-positive patches longer visible still detected outside 1B). adult epididymis significantly smaller WT 1C), closely resembling corresponding weight 1D). absence 1E). time course examined hematoxylin eosin staining Similar started age weeks: tubular lumen disorganized, many center tubule rather being inner walls control 3-week-old clusters degenerating tubules, were, however, mainly filled Such disappeared 4 weeks age, point different developmental stages. displayed syndrome. unable produce offspring during entire lifespan. contrast, showed signs 1E) fertile. Hence, dispensable maintaining spermatogenesis. blind because already day 14 (P14) 18Edwards Although epithelium (RPE) layers neuronal photoreceptors test hypothesis, Trp1-Cre (32Mori Metzger Garnier J.M. Chambon Mark Site-specific somatic epithelium.Invest. 43: 1384-1388PubMed RPE-?C2 specifically RPE. resembled 2). 2-week-old outer nuclear layer photoreceptor 2) disorganized At thinner model. completely residual parts This difference mosaic-like (33Thanos Morizane Y. Murakami Giani Mantopoulos Kayama Roh M.I. Michaud Pawlyk Sandberg Young L.H. Miller J.W. Vavvas D.G. Evidence baseline mouse.Am. Pathol. 180: 1917-1927Abstract (29) presumably spared ablation. buttress hypothesis secondary malfunction nurturing leads disrupti