|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
First published online 13 May 2008
doi: 10.1242/jcs.020321
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Research Article |


Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany
¶ Author for correspondence: (e-mail: b.dobberstein{at}zmbh.uni-heidelberg.de)
Accepted 2 March 2008
Tail-anchored (TA) proteins are characterised by a C-terminal transmembrane region that mediates post-translational insertion into the membrane of the endoplasmic reticulum (ER). We have investigated the requirements for membrane insertion of three TA proteins, RAMP4, Sec61β and cytocrome b5. We show here that newly synthesised RAMP4 and Sec61β can accumulate in a cytosolic, soluble complex with the ATPase Asna1 before insertion into ER-derived membranes. Membrane insertion of these TA proteins is stimulated by ATP, sensitive to redox conditions and blocked by alkylation of SH groups by N-ethylmaleimide (NEM). By contrast, membrane insertion of cytochrome b5 is not found to be mediated by Asna1, not stimulated by ATP and not affected by NEM or an oxidative environment. The Asna1-mediated pathway of membrane insertion of RAMP4 and Sec61β may relate to functions of these proteins in the ER stress response.
Key words: Tail-anchored protein, RAMP4, Sec61β, Cytochrome b5, Endoplasmic reticulum, Asna-1/TRC40
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati
Twitter What's this?
This article has been cited by other articles:
![]() |
S. F. Colombo, R. Longhi, and N. Borgese The role of cytosolic proteins in the insertion of tail-anchored proteins into phospholipid bilayers J. Cell Sci., July 15, 2009; 122(14): 2383 - 2392. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Saita, M. Shirane, T. Natume, S.-i. Iemura, and K. I. Nakayama Promotion of Neurite Extension by Protrudin Requires Its Interaction with Vesicle-associated Membrane Protein-associated Protein J. Biol. Chem., May 15, 2009; 284(20): 13766 - 13777. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. C. Jonikas, S. R. Collins, V. Denic, E. Oh, E. M. Quan, V. Schmid, J. Weibezahn, B. Schwappach, P. Walter, J. S. Weissman, et al. Comprehensive Characterization of Genes Required for Protein Folding in the Endoplasmic Reticulum Science, March 27, 2009; 323(5922): 1693 - 1697. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Rabu, P. Wipf, J. L. Brodsky, and S. High A Precursor-specific Role for Hsp40/Hsc70 during Tail-anchored Protein Integration at the Endoplasmic Reticulum J. Biol. Chem., October 10, 2008; 283(41): 27504 - 27513. [Abstract] [Full Text] [PDF] |
||||