دورية أكاديمية

Visualization of translation and protein biogenesis at the ER membrane

التفاصيل البيبلوغرافية
العنوان: Visualization of translation and protein biogenesis at the ER membrane
المؤلفون: Gemmer, Max, Chaillet, Marten L, van Loenhout, Joyce, Cuevas Arenas, Rodrigo, Vismpas, Dimitrios, Gröllers-Mulderij, Mariska, Koh, Fujiet A, Albanese, Pascal, Scheltema, Richard A, Howes, Stuart C, Kotecha, Abhay, Fedry, Juliette, Förster, Friedrich
المساهمون: Sub Structural Biochemistry, Afd Biomol.Mass Spect. and Proteomics, Structural Biochemistry, Biomolecular Mass Spectrometry and Proteomics
سنة النشر: 2023
مصطلحات موضوعية: Endoplasmic Reticulum/metabolism, Humans, Membrane Proteins/metabolism, Protein Biosynthesis, Protein Sorting Signals, Protein Transport, Ribosomes/metabolism, SEC Translocation Channels/chemistry, General
الوصف: The dynamic ribosome-translocon complex, which resides at the endoplasmic reticulum (ER) membrane, produces a major fraction of the human proteome 1,2. It governs the synthesis, translocation, membrane insertion, N-glycosylation, folding and disulfide-bond formation of nascent proteins. Although individual components of this machinery have been studied at high resolution in isolation 3-7, insights into their interplay in the native membrane remain limited. Here we use cryo-electron tomography, extensive classification and molecular modelling to capture snapshots of mRNA translation and protein maturation at the ER membrane at molecular resolution. We identify a highly abundant classical pre-translocation intermediate with eukaryotic elongation factor 1a (eEF1a) in an extended conformation, suggesting that eEF1a may remain associated with the ribosome after GTP hydrolysis during proofreading. At the ER membrane, distinct polysomes bind to different ER translocons specialized in the synthesis of proteins with signal peptides or multipass transmembrane proteins with the translocon-associated protein complex (TRAP) present in both. The near-complete atomic model of the most abundant ER translocon variant comprising the protein-conducting channel SEC61, TRAP and the oligosaccharyltransferase complex A (OSTA) reveals specific interactions of TRAP with other translocon components. We observe stoichiometric and sub-stoichiometric cofactors associated with OSTA, which are likely to include protein isomerases. In sum, we visualize ER-bound polysomes with their coordinated downstream machinery.
نوع الوثيقة: article in journal/newspaper
وصف الملف: application/pdf
اللغة: English
تدمد: 0028-0836
العلاقة: https://dspace.library.uu.nl/handle/1874/434047Test
الإتاحة: https://dspace.library.uu.nl/handle/1874/434047Test
حقوق: info:eu-repo/semantics/OpenAccess
رقم الانضمام: edsbas.B83D142
قاعدة البيانات: BASE