YidC is required for the assembly of the MscL homopentameric pore.
The mechanosensitive channel with large conductance (MscL) of Escherichia coli is formed by a homopentameric assembly of MscL proteins. Here, we describe MscL biogenesis as determined using in vivo approaches. Evidence is presented that MscL is targeted to the inner membrane via the signal recognition particle (SRP) pathway, and is inserted into the lipid bilayer independently of the Sec machinery. This is consistent with published data. Surprisingly, and in conflict with earlier data, YidC is not critical for membrane insertion of MscL. In the absence of YidC, assembly of the homopentameric MscL complex was strongly reduced, suggesting a late role for YidC in the biogenesis of MscL. The data are consistent with the view that YidC functions as a membrane-based chaperone 'module' to facilitate assembly of a subset of protein complexes in the inner membrane of E. coli.
Pop
Ovidiu I
OI
Section Molecular Microbiology, Department of Molecular Cell Biology, VU University, Amsterdam, The Netherlands.
Soprova
Zora
Z
Koningstein
Gregory
G
Scheffers
Dirk-Jan
DJ
van Ulsen
Peter
P
Wickström
David
D
de Gier
Jan-Willem
JW
Luirink
Joen
J
D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000502:physiology*; D007425:Intracellular Membranes / Q000378:metabolism; D007473:Ion Channels / Q000235:genetics / Q000502:physiology*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000502:physiology*; D009154:Mutation; D055503:Protein Multimerization; D018271:Signal Recognition Particle / Q000502:physiology
D029968:Escherichia coli Proteins; D007473:Ion Channels; D026901:Membrane Transport Proteins; C086596:MscL protein, E coli; D018271:Signal Recognition Particle; C412443:YIDC protein, E coli