Fig. 7.

DGC components are substrates of the impaired protein processing machinery in p.P104L caveolinopathy. A Immunoblots of paradigmatic components of the DGC confirm the proteomic findings by showing increased protein abundance of dystrophin, dysferlin, α- and β-dystroglycan, α-1-syntrophin as well as α-, β- and δ-sarcoglycan. Protein phosphatase 2AAA, stable in our proteome profile, has been used as loading control, and shows stable levels, in line with our proteomic findings. B Increased abundance of DGC components was also confirmed by immunohistochenistry focusing on δ-sarcoglycan as a paradigmatic example. Interestingly, apart from occasional sarcoplasmic deposits (black arrows in 7B.4), an enrichment in the sub-sarcolemmal region could be identified (7B.2 and 7B.3). C Immunofluorescence-based co-localization studies showing (irregular) sarcoplasmic dots immunoreactive for GRP170 (a co-chaperon of the SIL1-BiP machinery) and dysferlin. D Immunoblot analysis utilizing the monoclonal antibody IIH6, which recognizes specifically glycosylated α-dystroglycan (left panel) and the polyclonal antibody AF6868, which recognizes both α- and β-dystroglycan (right panel)