Functional and conformational properties of the exclusive C-domain from the Arabidopsis copper chaperone (CCH).
The Arabidopsis thaliana copper chaperone (CCH) is a small copper binding protein involved in copper trafficking. When compared to homologues from other eukaryotes, CCH has two different domains; the conserved N-domain and the plant-exclusive C-domain, a C-terminal extension with an unusual amino-acid composition. In order to characterize this extra C-domain, the CCH protein, the N-domain and the C-domain were all expressed separately in heterologous systems. While the N-domain retained the copper chaperone and antioxidant properties described for the yeast Atx1 and human HAH1 counterparts, the C-domain displayed particular structural properties that would be necessary to optimize copper homoeostasis in plant cells where it could be responsible for the metallochaperone plant-exclusive intercellular transport. The whole CCH protein and the C-domain, but not the N-domain, displayed altered SDS/PAGE mobilities. CD spectroscopy showed that the N-domain fold is representative of an alpha/beta protein, while the C-domain adopts an extended conformation.
Mira
H
H
Departament de Bioquímica i Biologia Molecular, Universitat de València, Avda. Dr Moliner 50, E-46100 Burjassot, València, Spain.
Vilar
M
M
Pérez-Payá
E
E
Peñarrubia
L
L
D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins; D002942:Circular Dichroism; D003001:Cloning, Molecular; D003300:Copper / Q000378:metabolism*; D005816:Genetic Complementation Test; D006801:Humans; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism*; D010940:Plant Proteins / Q000737:chemistry* / Q000378:metabolism*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism
D029681:Arabidopsis Proteins; C433183:CCH protein, Arabidopsis; D018832:Molecular Chaperones; D010940:Plant Proteins; D011994:Recombinant Proteins; D003300:Copper