A Caltech Library Service

Regulated assembly of the ER membrane protein complex

Pleiner, Tino and Januszyk, Kurt and Tomaleri, Giovani Pinton and Oania, Robert S. and Hazu, Masami and Sweredoski, Michael J. and Moradian, Annie and Guna, Alina and Voorhees, Rebecca M. (2020) Regulated assembly of the ER membrane protein complex. . (Unpublished)

[img] PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


The assembly of nascent proteins into multi-subunit complexes is tightly regulated to maintain cellular homeostasis. The ER membrane protein complex (EMC) is an essential insertase that requires seven membrane-spanning and two soluble subunits for function. Here we show that the kinase With no lysine 1 (WNK1), known for its role in hypertension and neuropathy, is required for assembly of the human EMC. WNK1 uses a conserved amphipathic helix to stabilize the soluble subunit, EMC2, by binding to the EMC2-8 interface. Shielding this hydrophobic surface prevents promiscuous interactions of unassembled EMC2 and precludes binding of ubiquitin ligases, permitting assembly. Using biochemical reconstitution, we show that after EMC2 reaches the membrane, its interaction partners within the EMC displace WNK1, and similarly shield its exposed hydrophobic surfaces. This work describes an unexpected role for WNK1 in protein biogenesis, and defines the general requirements of an assembly factor that will apply across the proteome.

Item Type:Report or Paper (Discussion Paper)
Related URLs:
URLURL TypeDescription Paper
Pleiner, Tino0000-0002-5104-0315
Januszyk, Kurt0000-0002-9076-4180
Tomaleri, Giovani Pinton0000-0001-9661-6480
Oania, Robert S.0000-0003-4070-761X
Hazu, Masami0000-0002-6527-9597
Sweredoski, Michael J.0000-0003-0878-3831
Moradian, Annie0000-0002-0407-2031
Guna, Alina0000-0003-0757-1255
Voorhees, Rebecca M.0000-0003-1640-2293
Additional Information:The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. Posted July 21, 2020. We thank Christian Schlieker for reagents and John O’Neill, Ramanujan Hegde, Henry Lester, and the Voorhees lab for thoughtful discussions. Confocal imaging was performed in the Caltech Biological Imaging Facility with the support of the Caltech Beckman Institute and the Arnold and Mabel Beckman Foundation. This work was supported by the Heritage Medical Research Institute, the Kinship Foundation, the Pew-Stewart Foundation, and the National Institute Of General Medical Sciences of the National Institutes of Health under Award Number DP2GM137412. T.P. is supported by a postdoctoral fellowship from the Deutsche Forschungsgemeinschaft and received prior funding from a Caltech Ross fellowship. Author contributions: T.P, A.G, and R.V. conceived the study. T.P., R.O, and M.H. performed the experiments. T.P., R.V., K.J., G.P.T., M.S., and A.M. analyzed the data. T.P. and R.V. wrote the manuscript with input from all authors. The authors declare no competing interests.
Group:Heritage Medical Research Institute
Funding AgencyGrant Number
Caltech Beckman InstituteUNSPECIFIED
Arnold and Mabel Beckman FoundationUNSPECIFIED
Heritage Medical Research InstituteUNSPECIFIED
Kinship FoundationUNSPECIFIED
Pew-Stewart FoundationUNSPECIFIED
Deutsche Forschungsgemeinschaft (DFG)UNSPECIFIED
Caltech Ross FellowshipUNSPECIFIED
Record Number:CaltechAUTHORS:20200722-105320999
Persistent URL:
Official Citation:Regulated assembly of the ER membrane protein complex. Tino Pleiner, Kurt Januszyk, Giovani Pinton Tomaleri, Robert S. Oania, Masami Hazu, Michael J. Sweredoski, Annie Moradian, Alina Guna, Rebecca M Voorhees. bioRxiv 2020.07.20.213066; doi:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:104508
Deposited By: Tony Diaz
Deposited On:22 Jul 2020 18:40
Last Modified:22 Jul 2020 18:40

Repository Staff Only: item control page