8dar
Saccharomyces cerevisiae Ufd1/Npl4/Cdc48 complex unbound but in the presence of SUMO-ubiquitin(K48polyUb)-mEOS and ATPSaccharomyces cerevisiae Ufd1/Npl4/Cdc48 complex unbound but in the presence of SUMO-ubiquitin(K48polyUb)-mEOS and ATP
Structural highlights
FunctionNPL4_YEAST Involved in the import of nuclear-targeted proteins into the nucleus and the export of poly(A) RNA out of the nucleus (PubMed:8930904, PubMed:11733065). Has a role in the endoplasmic reticulum-associated degradation (ERAD) pathway (PubMed:11739805, PubMed:11740563, PubMed:11847109). Required for the proteasome-dependent processing/activation of MGA2 and SPT23 transcription factors leading to the subsequent expression of OLE1 (PubMed:11733065). Has an additional role in the turnover of OLE1 where it targets ubiquitinated OLE1 and other proteins to the ERAD (PubMed:11847109). Regulates ubiquitin-mediated mitochondria protein degradation (PubMed:21070972). Involved in spindle disassembly probably by promoting the degradation of spindle assemby factors ASE1 and CDC5 at the end of mitosis (PubMed:14636562).[1] [2] [3] [4] [5] [6] [7] Publication Abstract from PubMedThe Ufd1/Npl4/Cdc48 complex is a universal protein segregase that plays key roles in eukaryotic cellular processes. Its functions orchestrating the clearance or removal of polyubiquitylated targets are established; however, prior studies suggest that the complex also targets substrates modified by the ubiquitin-like protein SUMO. Here, we show that interactions between Ufd1 and SUMO enhance unfolding of substrates modified by SUMO-polyubiquitin hybrid chains by the budding yeast Ufd1/Npl4/Cdc48 complex compared to substrates modified by polyubiquitin chains, a difference that is accentuated when the complex has a choice between these substrates. Incubating Ufd1/Npl4/Cdc48 with a substrate modified by a SUMO-polyubiquitin hybrid chain produced a series of single-particle cryo-EM structures that reveal features of interactions between Ufd1/Npl4/Cdc48 and ubiquitin prior to and during unfolding of ubiquitin. These results are consistent with cellular functions for SUMO and ubiquitin modifications and support a physical model wherein Ufd1/Npl4/Cdc48, SUMO, and ubiquitin conjugation pathways converge to promote clearance of proteins modified with SUMO and polyubiquitin. SUMO enhances unfolding of SUMO-polyubiquitin-modified substrates by the Ufd1/Npl4/Cdc48 complex.,Lee HG, Lemmon AA, Lima CD Proc Natl Acad Sci U S A. 2023 Jan 3;120(1):e2213703120. doi: , 10.1073/pnas.2213703120. Epub 2022 Dec 27. PMID:36574706[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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