title: Isolation, molecular characterization, and tissue-specific expression of ECP-51 and ECP-54 (TIP49), two homologous, interacting erythroid cytosolic proteins.
abstract: We isolated two proteins, ECP-51 and ECP-54, from human erythrocyte cytosol by affinity chromatography using a peptide of the integral membrane protein stomatin as bait. Partial amino acid sequence information obtained by microsequencing allowed us to clone the respective cDNAs. Analysis of the nucleotide sequences revealed that ECP-51 and ECP-54 are homologous (44.2% amino acid identity) and contain ATP-binding sites. ECP-54 was identified as TIP49/RUVBL1/NMP238, which is a component of a large nuclear protein complex, possibly the RNA polymerase II holoenzyme; ECP-51 is a novel protein. Using the two-hybrid system, we showed that these proteins interact with each other. The interaction of ECP-51 and ECP-54 with the stomatin peptide and the localization to the nucleus and cytoplasm suggest an additional function for these proteins as chaperone components.
authors.affiliation: Institute of Biochemistry, Medical Faculty, University of Vienna, Austria.
authors.forename: U
authors.initials: U
authors.lastname: Salzer
authors.forename: M
authors.initials: M
authors.lastname: Kubicek
authors.forename: R
authors.initials: R
authors.lastname: Prohaska
mesh_terms: D000074183:ATPases Associated with Diverse Cellular Activities; D000595:Amino Acid Sequence; D001798:Blood Proteins / Q000378:metabolism; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D003600:Cytosol / Q000378:metabolism; D004265:DNA Helicases; D017931:DNA Primers; D019992:Databases as Topic; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D001798:Blood Proteins; D002352:Carrier Proteins; D017931:DNA Primers; D008565:Membrane Proteins; C036860:STOM protein, human; D000074183:ATPases Associated with Diverse Cellular Activities; D004265:DNA Helicases; C486549:RUVBL1 protein, human; C122079:RUVBL2 protein, human