Syntaxin 7 is a broadly expressed SNARE. (A) A rabbit polyclonal anti-syntaxin 7 antibody recognizes a major 39-kDa band in HeLa cell PNS (control). This band represents endogenous syntaxin 7, because it can be blocked with 1 μg/ml recombinant syntaxin 7 (syntaxin 7) but not 1 μg/ml recombinant syntaxin 13 (syntaxin 13). (B) PNSs from Jurkat, CHO, HepG2, Madin–Darby canine kidney, Cos7, and 293 cell lines were analyzed using the anti-syntaxin 7 antibody. A single major 39-kDa band is detected in every cell line investigated.