Ipomoeassin F Binds Sec61α to Inhibit Protein Translocation
Year: 2019
Type: article
Abstract: Ipomoeassin F is a potent natural cytotoxin that inhibits growth of many tumor cell lines with single-digit nanomolar potency. However, its biological and pharmacological properties have remained largely unexplored. Building upon our earlier achievements in total synthesis and medicinal chemistry, we used chemical proteomics to identify Sec61α (protein transport protein Sec61 subunit alpha isoform 1), the pore-forming subunit of the Sec61 protein translocon, as a direct binding partner of ipomoeassin F in living cells. The interaction is specific and strong enough to survive lysis conditions, enabling a biotin analogue of ipomoeassin F to pull down Sec61α from live cells, yet it is also reversible, as judged by several experiments including fluorescent streptavidin staining, delayed competition in affinity pulldown, and inhibition of TNF biogenesis after washout. Sec61α forms the central subunit of the ER protein translocation complex, and the binding of ipomoeassin F results in a substantial, yet selective, inhibition of protein translocation in vitro and a broad ranging inhibition of protein secretion in live cells. Lastly, the unique resistance profile demonstrated by specific amino acid single-point mutations in Sec61α provides compelling evidence that Sec61α is the primary molecular target of ipomoeassin F and strongly suggests that the binding of this natural product to Sec61α is distinctive. Therefore, ipomoeassin F represents the first plant-derived, carbohydrate-based member of a novel structural class that offers new opportunities to explore Sec61α function and to further investigate its potential as a therapeutic target for drug discovery.
DOI: 10.1021/jacs.8b13506
Authors: Guanghui Zong, Zhijian Hu, Sarah O’Keefe, Dale Tranter, Michael J. Iannotti, Ludivine Baron, Belinda Hall, Katherine Corfield, Anja O. Paatero, Mark J. Henderson, Peristera Roboti, Jianhong Zhou, Xianwei Sun, Mugunthan Govindarajan, Jason M. Rohde, Nicolas Blanchard, Rachel Simmonds, James Inglese, Yuchun Du, Caroline Demangel, Stephen High, Ville O. Paavilainen, Wei Q. Shi
Institutions: University of Maryland, College Park, University of Arkansas at Fayetteville, University of Manchester, University of Helsinki, HiLIFE – Elämäntieteiden Instituutti, National Institutes of Health, National Center for Advancing Translational Sciences, Inserm, Institut Pasteur, University of Surrey, Baylor College of Medicine, Emory University, Centre National de la Recherche Scientifique, Université de Haute-Alsace, Laboratoire d'innovation moléculaire et applications, Université de Strasbourg, Ball State University
Language: English
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $2,258
Funders: Harvard University, University of Arkansas, Arkansas Biosciences Institute, Wellcome Trust, Agence Nationale de la Recherche, Institut National de la Santé et de la Recherche Médicale, Academy of Finland, Institut Pasteur, Centre National de la Recherche Scientifique, Sigrid Juséliuksen Säätiö, Fondation Raoul Follereau, National Institutes of Health, Directorate for Biological Sciences, Biotechnology and Biological Sciences Research Council, National Institute of General Medical Sciences, National Center for Advancing Translational Sciences
Awards: G1349507547, BB/J014478/1, G1746439804, Par-delà les frontières, l'Université de Strasbourg, G2788256771, The exploitation of mannosyltransferase inhibitors to modulate glycoprotein biogenesis and quality control, G5828548825, G5967992216, G6529548846, Center for Protein Structure and Function, G7316040300, Alpha-1 antitrypsin (AAT) deficiency, The quality control of mislocalised membrane and secretory proteins, Investigating the role of coagulation in the pathogenesis of Buruli ulcer, Medicinal Chemistry and Biomedical Studies of Open-Chain Mimics of Ipomoeassin Natural Glycoresins, G9000260244, Modulators of Secreted ER Ca2+ Monitoring Protein (SERCaMP)
OpenAlex ID: W2943937786