TY - JOUR

T1 - Twin-arginine translocation-arresting protein regions contact TatA and TatB

AU - Taubert, Johannes

AU - Brüser, Thomas

N1 - Funding Information: Acknowledgments: We thank Peter G. Schultz (The Scripps Research Institute, La Jolla) for donation of the pEVOL system, and Andrea Sinz and Christian Ihling (University of Halle-Wittenberg) for mass spectrometry analysis. This work was funded by the Deutsche Forschungsgemein-schaft (GRK 1026: ‘Conformational transitions during macromolecular interactions’). Copyright: Copyright 2014 Elsevier B.V., All rights reserved.

PY - 2014/7

Y1 - 2014/7

N2 - Tat systems translocate folded proteins across biological membranes of prokaryotes and plant plastids. TatBC complexes recognize N-Terminal Tat signal peptides that contain a sequence motif with two conserved arginines (RR-Motif), and transport takes place after a recruitment of TatA. Unfolded Tat substrate domains lower translocation efficiency and too long linkers lead to translocation arrest. To identify the components that interact with transported proteins during their passage through the translocon, we used a Tat substrate that arrests translocation at a long unfolded linker region, and we chose in vivo site-Directed photo cross-Linking to specifically detect the interactions of this linker region. For comparison, we included the interactions of the signal peptide and of the folded domain at the C-Terminus of this construct. The data show that the linker contacts only two, structurally similar Tat components, namely TatA and TatB. These contacts depend on the recognition of the Tat-Specific signal peptide. Only when membrane translocation of the globular domain was allowed - i.e., in the absence of the linker - we observed the same TatAB-Contacts also to the globular domain. The data thus suggest that mature protein domains are translocated through a TatAB environment.

AB - Tat systems translocate folded proteins across biological membranes of prokaryotes and plant plastids. TatBC complexes recognize N-Terminal Tat signal peptides that contain a sequence motif with two conserved arginines (RR-Motif), and transport takes place after a recruitment of TatA. Unfolded Tat substrate domains lower translocation efficiency and too long linkers lead to translocation arrest. To identify the components that interact with transported proteins during their passage through the translocon, we used a Tat substrate that arrests translocation at a long unfolded linker region, and we chose in vivo site-Directed photo cross-Linking to specifically detect the interactions of this linker region. For comparison, we included the interactions of the signal peptide and of the folded domain at the C-Terminus of this construct. The data show that the linker contacts only two, structurally similar Tat components, namely TatA and TatB. These contacts depend on the recognition of the Tat-Specific signal peptide. Only when membrane translocation of the globular domain was allowed - i.e., in the absence of the linker - we observed the same TatAB-Contacts also to the globular domain. The data thus suggest that mature protein domains are translocated through a TatAB environment.

KW - Membrane proteins

KW - Protein transport

KW - Protein-Protein interactions

KW - Tat system

KW - Twin-Arginine translocation

UR - http://www.scopus.com/inward/record.url?scp=84904199609&partnerID=8YFLogxK

U2 - 10.1515/hsz-2014-0170

DO - 10.1515/hsz-2014-0170

M3 - Article

C2 - 25003386

AN - SCOPUS:84904199609

VL - 395

SP - 827

EP - 836

JO - Biological Chemistry

JF - Biological Chemistry

SN - 1431-6730

IS - 7-8

ER -