402 Clinical and demographic features of hepatitis C-infected Alaska natives with persistently normal, persistantly elevated or fluxuating alanine transaminase levels

The aim of the present study was to identify a high affinity InsP4 receptor in membranes from cerebellum or brain from several species. In samples obtained from sheep, beef, human and rat, a 42 kDa protein represents an Ins(1,3,4,5)P4 receptor, similar to the InsP4 receptor from pig cerebellum, which we have described previously using an InsP4-photoaffinity analogue (Reiser et al., Biochem. J. 1991, 280, 533). CNBr cleavage of the pig receptor protein for peptide sequencing revealed peptide sequences which demonstrate that the 42 kDa InsP4 receptor is a novel protein. Two synthetic peptides derived from the pig receptor were used to generate peptide-specific antisera which recognized also the intact receptor protein from pig. The two antisera showed different reactivity with the InsP4 receptor purified from pig and human compared to sheep, beef and rat. This indicates a species heterogeneity of this protein.