SecY
SecY is the core membrane protein of the bacterial Sec translocon, a protein-conducting channel that moves polypeptides across and into membranes. In bacteria, SecY forms the SecYEG complex with SecE and SecG in the inner membrane, where it serves as the central conduit for secretory and membrane proteins. Preproteins bearing N-terminal signal peptides are targeted to the translocon by various pathways, including the SRP pathway and SecA-dependent routes, and SecY provides the channel through which these polypeptides pass. Translocation energy is provided by the ATPase SecA and, for some steps, the proton motive force.
Structurally, SecY is an integral membrane protein with multiple transmembrane helices that assemble to form a
SecY is highly conserved and is regarded as the prokaryotic counterpart to the eukaryotic Sec61 translocon.
See also: SecA, SecE, SecG, Sec61, protein translocation, SRP pathway.