First Author | Weinert S | Year | 2010 |
Journal | Science | Volume | 328 |
Issue | 5984 | Pages | 1401-3 |
PubMed ID | 20430974 | Mgi Jnum | J:160702 |
Mgi Id | MGI:4454959 | Doi | 10.1126/science.1188072 |
Citation | Weinert S, et al. (2010) Lysosomal pathology and osteopetrosis upon loss of H+-driven lysosomal Cl- accumulation. Science 328(5984):1401-3 |
abstractText | During lysosomal acidification, proton-pump currents are thought to be shunted by a chloride ion (Cl-) channel, tentatively identified as ClC-7. Surprisingly, recent data suggest that ClC-7 instead mediates Cl-/proton (H+) exchange. We generated mice carrying a point mutation converting ClC-7 into an uncoupled (unc) Cl- conductor. Despite maintaining lysosomal conductance and normal lysosomal pH, these Clcn7(unc/unc) mice showed lysosomal storage disease like mice lacking ClC-7. However, their osteopetrosis was milder, and they lacked a coat color phenotype. Thus, only some roles of ClC-7 Cl-/H+ exchange can be taken over by a Cl- conductance. This conductance was even deleterious in Clcn7(+/unc) mice. Clcn7(-/-) and Clcn7(unc/unc) mice accumulated less Cl- in lysosomes than did wild-type mice. Thus, lowered lysosomal chloride may underlie their common phenotypes. |