title: Small protein domains fold inside the ribosome exit tunnel.
abstract: Cotranslational folding of small protein domains within the ribosome exit tunnel may be an important cellular strategy to avoid protein misfolding. However, the pathway of cotranslational folding has so far been described only for a few proteins, and therefore, it is unclear whether folding in the ribosome exit tunnel is a common feature for small protein domains. Here, we have analyzed nine small protein domains and determined at which point during translation their folding generates sufficient force on the nascent chain to release translational arrest by the SecM arrest peptide, both in vitro and in live E. coli cells. We find that all nine protein domains initiate folding while still located well within the ribosome exit tunnel.
authors.affiliation: Gene Center and Center for Integrated Protein Science Munich, CiPS-M, University of Munich, Germany.
authors.forename: Jacopo
authors.identifier: http://orcid.org/0000-0001-7095-0800
authors.initials: J
authors.lastname: Marino
authors.affiliation: Department of Biochemistry and Biophysics, Center for Biomembrane Research, Stockholm University, Sweden.|Science for Life Laboratory, Stockholm University, Solna, Sweden.
authors.forename: Gunnar
authors.initials: G
authors.lastname: von Heijne
authors.affiliation: Gene Center and Center for Integrated Protein Science Munich, CiPS-M, University of Munich, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Beckmann
mesh_terms: D000818:Animals; D004926:Escherichia coli / Q000166:cytology / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008970:Molecular Weight; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D012270:Ribosomes / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D029968:Escherichia coli Proteins; C497347:SecM protein, E coli; D014157:Transcription Factors
keywords: GFP; SecM; cotranslational protein folding; fast-folding domains; ribosome exit tunnel; translational arrest