title: An optical assay of the transport activity of ClC-7.
abstract: Osteoporosis, characterized by excessive osteoclast mediated bone resorption, affects millions of people worldwide representing a major public health problem. ClC-7 is a chloride-proton exchanger localized in lysosomes and in the resorption lacuna in osteoclasts where it is essential for bone resorption. Thus, drugs targeted at ClC-7 have been proposed for ameliorating osteoporosis. However, functional assays suited for high throughput screening (HTS) of ClC-7 function are lacking. Here we describe two complementary variants of purely optical assays of the transport activity of ClC-7, redirected to the plasma membrane employing a genetically encoded fluorescent Cl⁻/pH indicator fused to the ClC-7 protein. These simple and robust functional assays of ClC-7 transport are well-suited to be applied in HTS of small-molecule inhibitors and may help to develop drugs suited for the treatment of osteoporosis.
authors: Istituto di Biofisica, CNR, Via De Marini 6, 16149 Genoa, Italy.
authors: Ilaria
authors: I
authors: Zanardi
authors: Giovanni
authors: G
authors: Zifarelli
authors: Michael
authors: M
authors: Pusch
mesh_terms: D001692:Biological Transport; D018118:Chloride Channels / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000737:chemistry; D057809:HEK293 Cells; D057166:High-Throughput Screening Assays; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008856:Microscopy, Fluorescence; D009154:Mutation; D010024:Osteoporosis / Q000378:metabolism / Q000473:pathology; D018408:Patch-Clamp Techniques; D011485:Protein Binding; D054852:Small Molecule Libraries / Q000737:chemistry / Q000378:metabolism*
chemical_list: C582873:CIC-7 protein, human; D018118:Chloride Channels; D005456:Fluorescent Dyes; D054852:Small Molecule Libraries
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