title: The ribosome triggers the stringent response by RelA via a highly distorted tRNA.
abstract: The bacterial stringent response links nutrient starvation with the transcriptional control of genes. This process is initiated by the stringent factor RelA, which senses the presence of deacylated tRNA in the ribosome as a symptom of amino-acid starvation to synthesize the alarmone (p)ppGpp. Here we report a cryo-EM study of RelA bound to ribosomes bearing cognate, deacylated tRNA in the A-site. The data show that RelA on the ribosome stabilizes an unusual distorted form of the tRNA, with the acceptor arm making contact with RelA and far from its normal location in the peptidyl transferase centre.
authors.affiliation: CIC bioGUNE, Structural Biology Unit, Bldg 800, Biscay Technology Park, Derio 48160, Basque Country, Spain.
authors.forename: Xabier
authors.initials: X
authors.lastname: Agirrezabala
authors.forename: Israel S
authors.initials: IS
authors.lastname: Fernández
authors.forename: Ann C
authors.initials: AC
authors.lastname: Kelley
authors.forename: David Gil
authors.initials: DG
authors.lastname: Cartón
authors.forename: Venki
authors.initials: V
authors.lastname: Ramakrishnan
authors.forename: Mikel
authors.initials: M
authors.lastname: Valle
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D004926:Escherichia coli / Q000737:chemistry / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism; D062105:Molecular Docking Simulation; D008969:Molecular Sequence Data; D012343:RNA, Transfer / Q000737:chemistry* / Q000378:metabolism; D012269:Ribosomal Proteins / Q000737:chemistry / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D051996:Transcription Factor RelA / Q000737:chemistry* / Q000378:metabolism
chemical_list: D029968:Escherichia coli Proteins; D012269:Ribosomal Proteins; D051996:Transcription Factor RelA; D012343:RNA, Transfer