title: von Hippel-Lindau protein binds hyperphosphorylated large subunit of RNA polymerase II through a proline hydroxylation motif and targets it for ubiquitination.
abstract: The transition from transcription initiation to elongation involves phosphorylation of the large subunit (Rpb1) of RNA polymerase II on the repetitive carboxyl-terminal domain. The elongating hyperphosphorylated Rpb1 is subject to ubiquitination, particularly in response to UV radiation and DNA-damaging agents. By using computer modeling, we identified regions of Rpb1 and the adjacent subunit 6 of RNA polymerase II (Rpb6) that share sequence and structural similarity with the domain of hypoxia-inducible transcription factor 1 alpha (HIF-1 alpha) that binds von Hippel-Lindau tumor suppressor protein (pVHL). pVHL confers substrate specificity to the E3 ligase complex, which ubiquitinates HIF-alpha and targets it for proteasomal degradation. In agreement with the computational model, we show biochemical evidence that pVHL specifically binds the hyperphosphorylated Rpb1 in a proline-hydroxylation-dependent manner, targeting it for ubiquitination. This interaction is regulated by UV radiation.
authors.affiliation: Department of Molecular and Cellular Physiology, Children's Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0576, USA.
authors.forename: Anna V
authors.initials: AV
authors.lastname: Kuznetsova
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Meller
authors.forename: Phillip O
authors.initials: PO
authors.lastname: Schnell
authors.forename: James A
authors.initials: JA
authors.lastname: Nash
authors.forename: Monika L
authors.initials: ML
authors.lastname: Ignacak
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Sanchez
authors.forename: Joan W
authors.initials: JW
authors.lastname: Conaway
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Conaway
authors.forename: Maria F
authors.initials: MF
authors.lastname: Czyzyk-Krzeska
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D019921:Biotinylation; D015153:Blotting, Western; D002467:Cell Nucleus / Q000378:metabolism; D004249:DNA Damage; D008025:Ligases / Q000378:metabolism* / Q000502:physiology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010100:Oxygen / Q000378:metabolism; D016716:PC12 Cells; D010766:Phosphorylation; D011233:Precipitin Tests; D011392:Proline / Q000737:chemistry; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012319:RNA Polymerase II / Q000737:chemistry* / Q000378:metabolism; D051381:Rats; D017386:Sequence Homology, Amino Acid; D012984:Software; D013379:Substrate Specificity; D025521:Tumor Suppressor Proteins; D025801:Ubiquitin / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases; D014466:Ultraviolet Rays; D051794:Von Hippel-Lindau Tumor Suppressor Protein
chemical_list: D025521:Tumor Suppressor Proteins; D025801:Ubiquitin; D011392:Proline; D044767:Ubiquitin-Protein Ligases; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D012319:RNA Polymerase II; D008025:Ligases; D010100:Oxygen