Toggle Main Menu Toggle Search

Open Access padlockePrints

A unifying mechanism for the biogenesis of membrane proteins co-operatively integrated by the Sec and Tat pathways

Lookup NU author(s): Professor Tracy Palmer FRS FRSE FMedSciORCiD



This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


© Tooke et al. The majority of multi-spanning membrane proteins are co-translationally inserted into the bilayer by the Sec pathway. An important subset of membrane proteins have globular, cofactor-containing extracytoplasmic domains requiring the dual action of the co-translational Sec and post-translational Tat pathways for integration. Here, we identify further unexplored families of membrane proteins that are dual Sec-Tat-targeted. We establish that a predicted heme-molybdenum cofactor-containing protein, and a complex polyferredoxin, each require the concerted action of two translocases for their assembly. We determine that the mechanism of handover from Sec to Tat pathway requires the relatively low hydrophobicity of the Tat-dependent transmembrane domain. This, coupled with the presence of C-terminal positive charges, results in abortive insertion of this transmembrane domain by the Sec pathway and its subsequent release at the cytoplasmic side of the membrane. Together, our data points to a simple unifying mechanism governing the assembly of dual targeted membrane proteins.

Publication metadata

Author(s): Tooke FJ, Babot M, Chandra G, Buchanan G, Palmer T

Publication type: Article

Publication status: Published

Journal: eLife

Year: 2017

Volume: 6

Online publication date: 17/05/2017

Acceptance date: 15/05/2017

Date deposited: 14/02/2019

ISSN (electronic): 2050-084X

Publisher: eLife Sciences Publications Ltd


DOI: 10.7554/eLife.26577

PubMed id: 28513434


Altmetrics provided by Altmetric


Funder referenceFunder name