title: On the Spatial Organization of mRNA, Plasmids, and Ribosomes in a Bacterial Host Overexpressing Membrane Proteins.
abstract: By using fluorescence imaging, we provide a time-resolved single-cell view on coupled defects in transcription, translation, and growth during expression of heterologous membrane proteins in Lactococcus lactis. Transcripts encoding poorly produced membrane proteins accumulate in mRNA-dense bodies at the cell poles, whereas transcripts of a well-expressed homologous membrane protein show membrane-proximal localization in a translation-dependent fashion. The presence of the aberrant polar mRNA foci correlates with cessation of cell division, which is restored once these bodies are cleared. In addition, activation of the heat-shock response and a loss of nucleoid-occluded ribosomes are observed. We show that the presence of a native-like N-terminal domain is key to SRP-dependent membrane localization and successful production of membrane proteins. The work presented gives new insights and detailed understanding of aberrant membrane protein biogenesis, which can be used for strategies to optimize membrane protein production.
authors.affiliation: Department of Molecular Genetics, University of Groningen, Groningen, The Netherlands.
authors.forename: Lieke A
authors.identifier: http://orcid.org/0000-0001-9381-7068
authors.initials: LA
authors.lastname: van Gijtenbeek
authors.affiliation: Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands.
authors.forename: Andrew
authors.initials: A
authors.lastname: Robinson
authors.affiliation: Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands.
authors.forename: Antoine M
authors.identifier: http://orcid.org/0000-0002-1794-5161
authors.initials: AM
authors.lastname: van Oijen
authors.affiliation: Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands.|Department of Biochemistry, University of Groningen, Groningen, The Netherlands.
authors.forename: Bert
authors.initials: B
authors.lastname: Poolman
authors.affiliation: Department of Molecular Genetics, University of Groningen, Groningen, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Kok
mesh_terms: D016764:Cell Polarity / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics; D013294:Lactococcus lactis / Q000235:genetics*; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics; D008856:Microscopy, Fluorescence; D010957:Plasmids / Q000096:biosynthesis / Q000235:genetics*; D014176:Protein Biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis; D012270:Ribosomes / Q000235:genetics
chemical_list: D008565:Membrane Proteins; D012333:RNA, Messenger