CFTR Folding Consortium: Methods Available for Studies of CFTR Folding and Correction
The CFTR Folding Consortium (CFC) was formed in 2004 under the auspices of the Cystic Fibrosis Foundation and its drug discovery and development affiliate, CFF Therapeutics. A primary goal of the CFC is the development and distribution of reagents and assay methods designed to better understand the mechanistic basis of mutant CFTR misfolding and to identify targets whose manipulation may correct CFTR folding defects. As such, reagents available from the CFC primarily target wild-type CFTR NBD1 and its common variant, F508del, and they include antibodies, cell lines, constructs, and proteins. These reagents are summarized here, and two protocols are described for the detection of cell surface CFTR: (a) an assay of the density of expressed HA-tagged CFTR by ELISA and (b) the generation and use of an antibody to CFTR’s first extracellular loop for the detection of endogenous CFTR. Finally, we highlight a systematic collection of assays, the CFC Roadmap, which is being used to assess the cellular locus and mechanism of mutant CFTR correction. The Roadmap queries CFTR structure–function relations at levels ranging from purified protein to well-differentiated human airway primary cultures.
Key wordsProtein folding protein degradation antibody generation cell surface protein detection research consortium www.cftrfolding.org
Resources providing support for this work in the Frizzell lab include grants from the NIH (DK068196 and DK 072506) and the Cystic Fibrosis Foundation (CFF R883-CR07 and FRIZZE05XX0). Experimental work in the laboratory of Gergely Lukacs was funded by the NIH, Cystic Fibrosis Folding Consortium, CIHR, and CFI. Tsukasa Okiyoneda was supported by a postdoctoral fellowship from the Canadian Cystic Fibrosis Foundation.
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