Articles

Common Principles of Protein Translocation Across Membranes

See allHide authors and affiliations

Science  15 Mar 1996:
Vol. 271, Issue 5255, pp. 1519-1526
DOI: 10.1126/science.271.5255.1519

Abstract

Most major systems that transport proteins across a membrane share the following features: an amino-terminal transient signal sequence on the transported protein, a targeting system on the cis side of the membrane, a hetero-oligomeric transmembrane channel that is gated both across and within the plane of the membrane, a peripherally attached protein translocation motor that is powered by the hydrolysis of nucleoside triphosphate, and a protein folding system on the trans side of the membrane. These transport systems are divided into two families: export systems that export proteins out of the cytosol, and import systems that transport proteins into cytosol-like compartments.