SecY and Sec61 translocons mediate the orderly insertion of transmembrane segments into the lipid bilayer during membrane-protein biogenesis. Reporting in this issue, Ismail et al. now use a SecM-based molecular force sensor to show that the translocon exerts a pulling force on the nascent chain that is capable of mechanical action at two distinct stages of the insertion process.
- Soo Jung Kim
- William R Skach
