Targeting of inositol 1,4,5-trisphosphate receptor to the endoplasmic reticulum by its first transmembrane domain.

ABSTRACT: Targeting of IP3R (inositol 1,4,5-trisphosphate receptors) to membranes of the ER (endoplasmic reticulum) and their retention within ER or trafficking to other membranes underlies their ability to generate spatially organized Ca2+ signals. N-terminal fragments of IP3R1 (type 1 IP3R) were tagged with enhanced green fluorescent protein, expressed in COS-7 cells and their distribution was determined by confocal microscopy and subcellular fractionation. Localization of IP3R1 in the ER requires translation of between 26 and 34 residues beyond the end of the first transmembrane domain (TMD1), a region that includes TMD2 (second transmembrane domain). Replacement of these post-TMD1 residues with unrelated sequences of similar length (24-36 residues) partially mimicked the native residues. We conc

SUBMITTER: Pantazaka E 

PROVIDER: S-EPMC2805921 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature