Premium
Synergism of Shrew‐1’s Signal Peptide and Transmembrane Segment Required for Plasma Membrane Localization
Author(s) -
Resch Eduard,
Quaiser Saskia,
Quaiser Tom,
Schneider Gisbert,
StarzinskiPowitz Anna,
Schreiner Alexander
Publication year - 2008
Publication title -
traffic
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.677
H-Index - 130
eISSN - 1600-0854
pISSN - 1398-9219
DOI - 10.1111/j.1600-0854.2008.00765.x
Subject(s) - biology , transmembrane protein , shrew , microbiology and biotechnology , signal peptide , membrane protein , integral membrane protein , protein subcellular localization prediction , subcellular localization , membrane , biochemistry , peptide sequence , receptor , gene , cytoplasm , ecology
Signal peptides (SP) and transmembrane segments (TMS) ensure proper subcellular targeting and localization of proteins. Thus, understanding the molecular variability of this targeting information is essential. In this study, we functionally analyzed the predicted SP and the TMS of adherens junction protein, shrew‐1 (Bharti et al. Novel membrane protein shrew‐1 targets to cadherin‐mediated junctions in polarized epithelial cells. Mol Biol Cell 2004:15:397). We used human secreted alkaline phosphatase (SEAP) as reporter protein. The SP of shrew‐1 was able to functionally substitute for SEAP’s intrinsic SP and was cleaved, indicating that it acts as a start‐transfer signal and not a signal anchor. In turn, the TMS of shrew‐1 functions as stop‐transfer signal. Notably, clearly detectable plasma membrane localization is only achieved when the fusion protein contains both the SP and the TMS of shrew‐1. In combination with the intrinsic SP from SEAP, the shrew‐1 TMS is unable to promote stable plasma membrane localization. Hence, it may be assumed that this synergism between an SP and a TMS to mediate plasma membrane localization is essential for structural and/or functional integrity of shrew‐1.