Milón, Pohl

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.lastpage","30"],["dc.bibliographiccitation.volume","430"],["dc.contributor.author","Milon, Pohl"],["dc.contributor.author","Konevega, Andrey L."],["dc.contributor.author","Peske, Frank"],["dc.contributor.author","Fabbretti, Attilio"],["dc.contributor.author","Gualerzi, Claudio O."],["dc.contributor.author","Rodnina, Marina"],["dc.contributor.editor","Ziegler, Christine"],["dc.date.accessioned","2017-09-07T11:49:53Z"],["dc.date.available","2017-09-07T11:49:53Z"],["dc.date.issued","2007"],["dc.description.abstract","Initiation of mRNA translation in prokaryotes requires the small ribosomat subunit (30S), initiator fMet-tRNA(fMet), three initiation factors, IF1, IF2, and IF3, and the large ribosomal subunit (50S). During initiation, the 30S subunit, in a complex with IF3, binds mRNA, IF1, IF2-GTP, and fMet-tRNA(fMet) to form a 30S initiation complex which then recruits the 50S subunit to yield a 70S initiation complex, while the initiation factors are released. Here we describe a transient kinetic approach to study the timing of elemental steps Of 30S initiation complex formation, 50S subunit joining, and the dissociation of the initiation factors from the 70S initiation complex. Labeling of ribosomal subunits, fMet-tRNA(fMet), mRNA, and initiation factors with fluorescent reporter groups allows for the direct observation of the formation or dissociation of complexes by monitoring changes in the fluorescence of single dyes or fluorescence resonance energy transfer (FRET) between two fluorophores. Subunit joining was monitored by light scattering or by FRET between dyes attached to the ribosomat subunits. The kinetics of chemical steps, that is, GTP hydrolysis by IF2 and peptide bond formation following the binding of aminoacyl-tRNA to the 70S initiation complex, were measured by the quench-ftow technique. The methods described here are based on results obtained with initiation components from Escherichia coli but can be adopted for mechanistic studies of initiation in other prokaryotic or eukaryotic systems."],["dc.identifier.doi","10.1016/S0076-6879(07)30001-3"],["dc.identifier.gro","3143569"],["dc.identifier.isi","000250402400001"],["dc.identifier.pmid","17913632"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/1097"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Elsevier Academic Press Inc"],["dc.publisher.place","San diego"],["dc.relation.crisseries","Methods in Enzymology"],["dc.relation.isbn","978-0-12-373969-8"],["dc.relation.ispartof","Methods in enzymology"],["dc.relation.ispartofseries","Methods in Enzymology"],["dc.relation.issn","0076-6879"],["dc.title","Transient kinetics, fluorescence, and fret in studies of initiation of translation in bacteria"],["dc.type","book_chapter"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","712"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Molecular Cell"],["dc.bibliographiccitation.lastpage","720"],["dc.bibliographiccitation.volume","30"],["dc.contributor.author","Milon, Pohl"],["dc.contributor.author","Konevega, Andrey L."],["dc.contributor.author","Gualerzi, Claudio O."],["dc.contributor.author","Rodnina, Marina V."],["dc.date.accessioned","2017-09-07T11:48:17Z"],["dc.date.available","2017-09-07T11:48:17Z"],["dc.date.issued","2008"],["dc.description.abstract","The translation initiation efficiency of a given mRNA is determined by its translation initiation region (TIR). mRNAs are selected into 30S initiation complexes according to the strengths of the secondary structure of the TIR, the pairing of the Shine-Dalgarno sequence with 16S rRNA, and the interaction between initiator tRNA and the start codon. Here, we show that the conversion of the 30S initiation complex into the translating 70S ribosome constitutes another important mRNA control checkpoint. Kinetic analysis reveals that 50S subunit joining and dissociation of IF3 are strongly influenced by the nature of the codon used for initiation and the structural elements of the TIR. Coupling between the TIR and the rate of 70S initiation complex formation involves IF3- and IF1-induced rearrangements of the 30S subunit, providing a mechanism by which the ribosome senses the TIR and determines the efficiency of translational initiation of a particular mRNA."],["dc.identifier.doi","10.1016/j.molcel.2008.04.014"],["dc.identifier.gro","3143278"],["dc.identifier.isi","000256984300006"],["dc.identifier.pmid","18570874"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/774"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","1097-2765"],["dc.title","Kinetic checkpoint at a late step in translation initiation"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","13962"],["dc.bibliographiccitation.issue","38"],["dc.bibliographiccitation.journal","Proceedings of the National Academy of Sciences"],["dc.bibliographiccitation.lastpage","13967"],["dc.bibliographiccitation.volume","103"],["dc.contributor.author","Milon, Pohl"],["dc.contributor.author","Tischenko, Eugene"],["dc.contributor.author","Tomsic, Jerneja"],["dc.contributor.author","Caserta, Enrico"],["dc.contributor.author","Folkers, Gert"],["dc.contributor.author","La Teana, Anna"],["dc.contributor.author","Rodnina, Marina"],["dc.contributor.author","Pon, Cynthia L."],["dc.contributor.author","Boelens, Rolf"],["dc.contributor.author","Gualerzi, Claudio O."],["dc.date.accessioned","2017-09-07T11:52:32Z"],["dc.date.available","2017-09-07T11:52:32Z"],["dc.date.issued","2006"],["dc.description.abstract","Translational initiation factor 2 (1172) is a guanine nucleotide-binding protein that can bind guanosine 3',5'-(bis) diphosphate (ppGpp), an alarmone involved in stringent response in bacteria. in cells growing under optimal conditions, the GTP concentration is very high, and that of ppGpp very low. However, under stress conditions, the GTP concentration may decline by as much as 50%, and that of ppGpp can attain levels comparable to those of GTP. Here we show that IF2 binds ppGpp at the same nucleoticle-binding site and with similar affinity as GTP. Thus, GTP and the alarmone ppGpp can be considered two alternative physiologically relevant IF2 ligands. ppGpp interferes with IF2-dependent initiation complex formation, severely inhibits initiation dipeptide formation, and blocks the initiation step of translation. Our data suggest that IF2 has the properties of a cellular metabolic sensor and regulator that oscillates between an active GTP-bound form under conditions allowing active protein syntheses and an inactive ppGpp-bound form when shortage of nutrients would be detrimental, if not accompanied by slackening of this synthesis."],["dc.identifier.doi","10.1073/pnas.0606384103"],["dc.identifier.gro","3143624"],["dc.identifier.isi","000240746600013"],["dc.identifier.pmid","16968770"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/1159"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Natl Acad Sciences"],["dc.relation.issn","0027-8424"],["dc.title","The nucleotide-binding site of bacterial translation initiation factor 2 (IF2) as a metabolic sensor"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","609"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Nature Structural & Molecular Biology"],["dc.bibliographiccitation.lastpage","615"],["dc.bibliographiccitation.volume","19"],["dc.contributor.author","Milón, Pohl"],["dc.contributor.author","Maracci, Cristina"],["dc.contributor.author","Filonava, Liudmila"],["dc.contributor.author","Gualerzi, Claudio O."],["dc.contributor.author","Rodnina, Marina V."],["dc.date.accessioned","2018-01-29T12:51:27Z"],["dc.date.available","2018-01-29T12:51:27Z"],["dc.date.issued","2012"],["dc.description.abstract","Initiation factors guide the ribosome in the selection of mRNA and translational reading frame. We determined the kinetically favored assembly pathway of the 30S preinitiation complex (30S PIC), an early intermediate in 30S initiation complex formation in Escherichia coli. IF3 and IF2 are the first factors to arrive, forming an unstable 30S-IF2-IF3 complex. Subsequently, IF1 joins and locks the factors in a kinetically stable 30S PIC to which fMet-tRNA(fMet) is recruited. Binding of mRNA is independent of initiation factors and can take place at any time during 30S PIC assembly, depending on the cellular concentration of the mRNA and the structural determinants at the ribosome-binding site. The kinetic analysis shows both specific and cumulative effects of initiation factors as well as kinetic checkpoints of mRNA selection at the entry into translation."],["dc.identifier.doi","10.1038/nsmb.2285"],["dc.identifier.pmid","22562136"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/11883"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.eissn","1545-9985"],["dc.title","Real-time assembly landscape of bacterial 30S translation initiation complex"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","312"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","EMBO reports"],["dc.bibliographiccitation.lastpage","316"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Milon, Pohl"],["dc.contributor.author","Carotti, Marcello"],["dc.contributor.author","Konevega, Andrey L."],["dc.contributor.author","Wintermeyer, Wolfgang"],["dc.contributor.author","Rodnina, Marina V."],["dc.contributor.author","Gualerzi, Claudio O."],["dc.date.accessioned","2017-09-07T11:46:06Z"],["dc.date.available","2017-09-07T11:46:06Z"],["dc.date.issued","2010"],["dc.description.abstract","Bacterial translation initiation factor 2 (IF2) is a GTPase that promotes the binding of the initiator fMet-tRNA(fMet) to the 30S ribosomal subunit. It is often assumed that IF2 delivers fMet-tRNA(fMet) to the ribosome in a ternary complex, IF2. GTP. fMet-tRNA(fMet). By using rapid kinetic techniques, we show here that binding of IF2. GTP to the 30S ribosomal subunit precedes and is independent of fMet-tRNA(fMet) binding. The ternary complex formed in solution by IF2. GTP and fMet-tRNA is unstable and dissociates before IF2. GTP and, subsequently, fMet-tRNA(fMet) bind to the 30S subunit. Ribosome-bound IF2 might accelerate the recruitment of fMet-tRNA(fMet) to the 30S initiation complex by providing anchoring interactions or inducing a favourable ribosome conformation. The mechanism of action of IF2 seems to be different from that of tRNA carriers such as EF-Tu, SelB and eukaryotic initiation factor 2 (eIF2), instead resembling that of eIF5B, the eukaryotic subunit association factor."],["dc.identifier.doi","10.1038/embor.2010.12"],["dc.identifier.gro","3142942"],["dc.identifier.isi","000276117100017"],["dc.identifier.pmid","20224578"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/401"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","1469-221X"],["dc.title","The ribosome-bound initiation factor 2 recruits initiator tRNA to the 30S initiation complex"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]