PMID: 28802041

Authors:

Bausewein T, Mills DJ, Langer JD, Nitschke B, Nussberger S, Kuhlbrandt W

Title:

Cryo-EM Structure of the TOM Core Complex from Neurospora crassa.

Journal:

Cell. 2017 Aug 10;170(4):693-700.e7. doi: 10.1016/j.cell.2017.07.012.

Abstract:

The TOM complex is the main entry gate for protein precursors from the cytosol into mitochondria. We have determined the structure of the TOM core complex by cryoelectron microscopy (cryo-EM). The complex is a 148 kDa symmetrical dimer of ten membrane protein subunits that create a shallow funnel on the cytoplasmic membrane surface. In the core of the dimer, the beta-barrels of the Tom40 pore form two identical preprotein conduits. Each Tom40 pore is surrounded by the transmembrane segments of the alpha-helical subunits Tom5, Tom6, and Tom7. Tom22, the central preprotein receptor, connects the two Tom40 pores at the dimer interface. Our structure offers detailed insights into the molecular architecture of the mitochondrial preprotein import machinery.