Sec-dependent membrane protein insertion: sequential interaction of nascent FtsQ with SecY and YidC.
Recent studies identified YidC as a novel membrane factor that may play a key role in membrane insertion of inner membrane proteins (IMPs), both in conjunction with the Sec-translocase and as a separate entity. Here, we show that the type II IMP FtsQ requires both the translocase and, to a lesser extent, YidC in vivo. Using photo-crosslinking we demonstrate that the transmembrane (TM) domain of the nascent IMP FtsQ inserts into the membrane close to SecY and lipids, and moves to a combined YidC/lipid environment upon elongation. These data are consistent with a crucial role for YidC in the lateral transfer of TM domains from the Sec translocase into the lipid bilayer.
Urbanus
M L
ML
Department of Microbiology, Institute of Molecular Biological Sciences, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands.
Scotti
P A
PA
Froderberg
L
L
Saaf
A
A
de Gier
J W
JW
Brunner
J
J
Samuelson
J C
JC
Dalbey
R E
RE
Oudega
B
B
Luirink
J
J
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000201:enzymology / Q000378:metabolism; D029968:Escherichia coli Proteins; D050356:Lipid Metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D026901:Membrane Transport Proteins; D008954:Models, Biological; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism; D000069816:SEC Translocation Channels; D000081416:SecA Proteins
D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C068023:FtsQ protein, E coli; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D012333:RNA, Messenger; D000069816:SEC Translocation Channels; C057841:SecY protein, E coli; C412443:YIDC protein, E coli; D000251:Adenosine Triphosphatases; D000081416:SecA Proteins