title: Expression and characterization of HSPC129, a RNA polymerase II C-terminal domain phosphatase.
abstract: Phosphorylation status of RNA polymerase (RNAP) II's largest subunit C-terminal domain (CTD) plays an important role during transcription cycles. The reversible phosphorylation mainly occurs at serine 2 and serine 5 of CTD heptapeptide repeats and regulates RNAP II's activity during transcription initiation, elongation and RNA processing. Here we expressed and characterized HSPC129, a putative human protein bearing a CTD phosphatase domain (CPD). PCR analysis showed that it was ubiquitously expressed. HSPC129DeltaTM, the truncate HSPC129 with first 156 N terminal amino acids deleted, exhibited Mg(2+) dependent phosphatase activity at pH 5.0. Its specific CTD phosphatase activity was verified in vitro. Our research suggests that HSPC129 may regulate the dynamic phosphorylation of RNAP II CTD.
authors.affiliation: State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Room 602, Science Building, Shanghai, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Qian
authors.forename: Chaoneng
authors.initials: C
authors.lastname: Ji
authors.forename: Shuo
authors.initials: S
authors.lastname: Zhao
authors.forename: Jinzhong
authors.initials: J
authors.lastname: Chen
authors.forename: Mei
authors.initials: M
authors.lastname: Jiang
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Mi
authors.initials: M
authors.lastname: Yan
authors.forename: Dan
authors.initials: D
authors.lastname: Zheng
authors.forename: Yaqiong
authors.initials: Y
authors.lastname: Sun
authors.forename: Yi
authors.initials: Y
authors.lastname: Xie
authors.forename: Yumin
authors.initials: Y
authors.lastname: Mao
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D019295:Computational Biology; D005786:Gene Expression Regulation; D006801:Humans; D008274:Magnesium / Q000378:metabolism; D008969:Molecular Sequence Data; D010749:Phosphoprotein Phosphatases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D010766:Phosphorylation; D017434:Protein Structure, Tertiary; D012319:RNA Polymerase II / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
chemical_list: D012319:RNA Polymerase II; D010749:Phosphoprotein Phosphatases; D008274:Magnesium