Signal peptidase can cleave inside a polytopic membrane protein

FEBS Letters

Beltzer, James P.¹  Wessels, Hans Peter¹  Spiess, Martin¹ 

[1] Department of Biochemistry, Biocenter, University of Basel, CH-4056 Basel, Switzerland

关键词: Asialoglycoprotein receptor;    Signal peptidase;    Polytopic membrane protein;    Hemagglutinin;   

DOI  :  10.1016/0014-5793(89)80937-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The signal peptides of most proteins targeted to the endoplasmic reticulum are specifically cleaved by signal peptidase. Although potential cleavage sites occur frequently in polytopic proteins after membrane-spanning segments, processing is restricted to the first hydrophobic domain, suggesting that signal peptidase might not have access to subsequently translocated, internal domains. To test this hypothesis, we replaced the third transmembrane segment of an artificial threefold membrane-spanning protein by a sequence which is normally an amino-terminal signal. Upon in vitro translation and insertion into microsomes, efficient cleavage at this sequence was observed, thus demonstrating the ability of signal peptidase to cleave within polytopic membrane proteins.

【 授权许可】

Unknown