ABSTRACT Proteins enter the secretory pathway through the endoplasmic reticulum1, which delivers properly folded proteins to their site of action2 and contains a quality-control system to

monitor and prevent abnormal proteins from being delivered3. Many of these proteins are degraded by the cytoplasmic proteasome4,5,6,7,8, which requires their retrograde transport to the

cytoplasm5,6. Based on a co-immunoprecipitation of major histocompatibility complex (MHC) class I heavy-chain breakdown intermediates with the translocon subunit Sec61p (refs 9, 10), it was

speculated that Sec61p may be involved in retrograde transport11. Here we present functional evidence from genetic studies that Sec61p mediates retrograde transport of a mutated lumenal

proteins to the cytosol by the translocon for proteasome degradation to be a general process in eukaryotic cell biology. Access through your institution Buy or subscribe This is a preview of

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PROCESSING DURING ER-ASSOCIATED PROTEIN DEGRADATION Article 01 August 2023 STRUCTURE AND TRANSPORT MECHANISM OF P5B-ATPASES Article Open access 25 June 2021 THE ROLE OF RNF149 IN THE

PRE-EMPTIVE QUALITY CONTROL SUBSTRATE UBIQUITINATION Article Open access 08 April 2023 REFERENCES * Pryer, N. K., Wuestehube, L. J. & Schekman, R. Vesicle-mediated protein sorting.

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(_kar2-113_ allele), T. A. Rapoport (Sec61p antibodies), H. K. Rudolph and R. Schekman (Kar2 antibodies), M. Knop (polyclonal CPY antibodies) and S. Rupp (proteinase yscA antibodies) for

providing gene constructs and affinity purified antibodies; and S. Jäger and M. Hämmerle for discussions. This work was supported by the Bundesministerium für Forschung und Technologie and

the Fonds der Chemischen Industrie, Frankfurt. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Institut für Biochemie der Universität Stuttgart, Pfaffenwaldring 55, D-70569, Stuttgart, Germany

Richard K. Plemper, Sigrun Böhmler, Javier Bordallo & Dieter H. Wolf * Max-Delbrück-Centrum für Molekulare Medizin, Robert-Rössle Strasse 10, D-13122, Berlin, Germany Thomas Sommer

Authors * Richard K. Plemper View author publications You can also search for this author inPubMed Google Scholar * Sigrun Böhmler View author publications You can also search for this

author inPubMed Google Scholar * Javier Bordallo View author publications You can also search for this author inPubMed Google Scholar * Thomas Sommer View author publications You can also

search for this author inPubMed Google Scholar * Dieter H. Wolf View author publications You can also search for this author inPubMed Google Scholar RIGHTS AND PERMISSIONS Reprints and

permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Plemper, R., Böhmler, S., Bordallo, J. _et al._ Mutant analysis links the translocon and BiP to retrograde protein transport for ER

degradation. _Nature_ 388, 891–895 (1997). https://doi.org/10.1038/42276 Download citation * Received: 14 July 1997 * Accepted: 31 July 1997 * Issue Date: 28 August 1997 * DOI:

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