title: Phosphorylation of Elp1 by Hrr25 is required for elongator-dependent tRNA modification in yeast.
abstract: Elongator is a conserved protein complex comprising six different polypeptides that has been ascribed a wide range of functions, but which is now known to be required for modification of uridine residues in the wobble position of a subset of tRNAs in yeast, plants, worms and mammals. In previous work, we showed that Elongator's largest subunit (Elp1; also known as Iki3) was phosphorylated and implicated the yeast casein kinase I Hrr25 in Elongator function. Here we report identification of nine in vivo phosphorylation sites within Elp1 and show that four of these, clustered close to the Elp1 C-terminus and adjacent to a region that binds tRNA, are important for Elongator's tRNA modification function. Hrr25 protein kinase directly modifies Elp1 on two sites (Ser-1198 and Ser-1202) and through analyzing non-phosphorylatable (alanine) and acidic, phosphomimic substitutions at Ser-1198, Ser-1202 and Ser-1209, we provide evidence that phosphorylation plays a positive role in the tRNA modification function of Elongator and may regulate the interaction of Elongator both with its accessory protein Kti12 and with Hrr25 kinase.
authors.affiliation: Centre for Gene Regulation & Expression, College of Life Sciences, University of Dundee, Dundee, United Kingdom; Institut für Biologie, FG Mikrobiologie, Universität Kassel, Germany.
authors.forename: Wael
authors.initials: W
authors.lastname: Abdel-Fattah
authors.affiliation: Institut für Biologie, FG Mikrobiologie, Universität Kassel, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Jablonowski
authors.affiliation: Centre for Gene Regulation & Expression, College of Life Sciences, University of Dundee, Dundee, United Kingdom.
authors.forename: Rachael
authors.initials: R
authors.lastname: Di Santo
authors.affiliation: Institut für Pharmazie und Biochemie, Johannes Gutenberg-Universität Mainz, Germany.
authors.forename: Kathrin L
authors.initials: KL
authors.lastname: Thüring
authors.affiliation: Institut für Biologie, FG Mikrobiologie, Universität Kassel, Germany.
authors.forename: Viktor
authors.initials: V
authors.lastname: Scheidt
authors.affiliation: Institut für Biologie, FG Mikrobiologie, Universität Kassel, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Hammermeister
authors.affiliation: Centre for Gene Regulation & Expression, College of Life Sciences, University of Dundee, Dundee, United Kingdom.
authors.forename: Sara
authors.initials: S
authors.lastname: Ten Have
authors.affiliation: Institut für Pharmazie und Biochemie, Johannes Gutenberg-Universität Mainz, Germany.
authors.forename: Mark
authors.initials: M
authors.lastname: Helm
authors.affiliation: Institut für Biologie, FG Mikrobiologie, Universität Kassel, Germany; Department of Genetics, University of Leicester, Leicester, United Kingdom.
authors.forename: Raffael
authors.initials: R
authors.lastname: Schaffrath
authors.affiliation: Centre for Gene Regulation & Expression, College of Life Sciences, University of Dundee, Dundee, United Kingdom.
authors.forename: Michael J R
authors.initials: MJ
authors.lastname: Stark
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics; D000409:Alanine / Q000235:genetics; D047389:Casein Kinase I / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D051548:Histone Acetyltransferases / Q000235:genetics* / Q000378:metabolism; D046912:Multiprotein Complexes / Q000235:genetics; D010445:Peptide Elongation Factors / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D010766:Phosphorylation; D012343:RNA, Transfer / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism; D014529:Uridine / Q000235:genetics
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C088889:KTI12 protein, S cerevisiae; D046912:Multiprotein Complexes; D010445:Peptide Elongation Factors; D029701:Saccharomyces cerevisiae Proteins; D012343:RNA, Transfer; D051548:Histone Acetyltransferases; C479559:IKI3 protein, S cerevisiae; D047389:Casein Kinase I; C070775:HRR25 protein, S cerevisiae; D000409:Alanine; D014529:Uridine