The DNA-binding activity of protein disulfide isomerase ERp57 is associated with the a(') domain.
ERp57 belongs to the protein disulfide isomerases, a family of homologous proteins mainly localized in the endoplasmic reticulum and characterized by the presence of a thioredoxin-like folding domain. ERp57 is a protein chaperone with thiol-dependent protein disulfide isomerase and additional activities and recently it has been shown to be involved, in cooperation with calnexin or with calreticulin, in the correct folding of glycoproteins. However, we have demonstrated that the same protein is also present in the nucleus, mainly associated with the internal nuclear matrix fraction. In vitro studies have shown that ERp57 has DNA-binding properties which are strongly dependent on its redox state, the oxidized form being the competent one. A comparison study on a recombinant form of ERp57 and several deletion mutants, obtained as fusion proteins and expressed in Escherichia coli, allowed us to identify the C-terminal a(') domain as directly involved in the DNA-binding activity of ERp57.
Grillo
Caterina
C
Dipartimento di Scienze Biochimiche A. Rossi-Fanelli, Centro di Biologia Molecolare del CNR and Istituto Pasteur-Fondazione Cenci Bolognetti, Università La Sapienza, P. le A. Moro 5, 00185 Rome, Italy.
Coppari
Sabina
S
Turano
Carlo
C
Altieri
Fabio
F
D000818:Animals; D026501:Blotting, Southwestern; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D006360:Heat-Shock Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D007535:Isomerases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008099:Liver / Q000201:enzymology; D019704:Protein Disulfide-Isomerases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013552:Swine
D004268:DNA-Binding Proteins; D006360:Heat-Shock Proteins; D011993:Recombinant Fusion Proteins; D007535:Isomerases; D019704:Protein Disulfide-Isomerases