title: Phosphorylation of the human La antigen on serine 366 can regulate recycling of RNA polymerase III transcription complexes.
abstract: The human La antigen is an RNA-binding protein that facilitates transcriptional termination and reinitiation by RNA polymerase III. Native La protein fractionates into transcriptionally active and inactive forms that are unphosphorylated and phosphorylated at serine 366, respectively, as determined by enzymatic and mass spectrometric analyses. Serine 366 comprises a casein kinase II phosphorylation site that resides within a conserved region in the La proteins from several species. RNA synthesis from isolated transcription complexes is inhibited by casein kinase II-mediated phosphorylation of La serine 366 and is reversible by dephosphorylation. This work demonstrates a novel mechanism of transcriptional control at the level of recycling of stable transcription complexes.
authors.affiliation: Laboratory of Molecular Growth Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: H
authors.initials: H
authors.lastname: Fan
authors.forename: A L
authors.initials: AL
authors.lastname: Sakulich
authors.forename: J L
authors.initials: JL
authors.lastname: Goodier
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.forename: J
authors.initials: J
authors.lastname: Qin
authors.forename: R J
authors.initials: RJ
authors.lastname: Maraia
mesh_terms: D001324:Autoantigens / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D015153:Blotting, Western; D047390:Casein Kinase II; D002458:Cell Fractionation; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism; D006367:HeLa Cells / Q000201:enzymology; D006801:Humans; D007525:Isoelectric Focusing; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000302:isolation & purification / Q000378:metabolism; D012320:RNA Polymerase III / Q000235:genetics* / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D012694:Serine / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D014158:Transcription, Genetic / Q000502:physiology; D000097585:SS-B Antigen
chemical_list: D001324:Autoantigens; D047390:Casein Kinase II; D004268:DNA-Binding Proteins; D017346:Protein Serine-Threonine Kinases; D012320:RNA Polymerase III; D012261:Ribonucleoproteins; D012694:Serine; D014157:Transcription Factors; D000097585:SS-B Antigen