title: Interaction of nucleoredoxin with protein phosphatase 2A.
abstract: A trimeric protein phosphatase 2A (PP2A(T55)) composed of the catalytic (PP2Ac), structural (PR65/A), and regulatory (PR55/B) subunits was isolated from rabbit skeletal muscle by thiophosphorylase affinity chromatography, and contained two additional proteins of 54 and 55 kDa, respectively. The 54 kDa protein was identified as eukaryotic translation termination factor 1 (eRF1) and as a PP2A interacting protein. The 55 kDa protein is now identified as nucleoredoxin (NRX). The formation of a complex between GST-NRX, PP2A(C) and PP2A(D) was demonstrated by pull-down experiments with purified forms of PP2A, and by immunoprecipitation of HA-tagged NRX expressed in HEK293 cells complexed endogenous PP2A subunits. Analysis of PP2A activity in the presence of GST-NRX showed that NRX competed with polycations for both stimulatory and inhibitory effects on different forms of PP2A.
authors.affiliation: Cell and Molecular Signalling Laboratory, Intercollegiate Faculty of Biotechnology UG-MUG, Gdansk, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Lechward
authors.forename: Ewa
authors.initials: E
authors.lastname: Sugajska
authors.forename: Ivo
authors.initials: I
authors.lastname: de Baere
authors.forename: Jozef
authors.initials: J
authors.lastname: Goris
authors.forename: Brian A
authors.initials: BA
authors.lastname: Hemmings
authors.forename: Stanislaw
authors.initials: S
authors.lastname: Zolnierowicz
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D019281:Dimerization; D005786:Gene Expression Regulation; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000302:isolation & purification / Q000378:metabolism*; D011485:Protein Binding; D054648:Protein Phosphatase 2; D011817:Rabbits; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D009687:Nuclear Proteins; D011994:Recombinant Proteins; D010088:Oxidoreductases; C105231:nucleoredoxin; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2