title: Crystallographic and functional analyses of J-domain of JAC1 essential for chloroplast photorelocation movement in Arabidopsis thaliana.
abstract: An auxilin-like J-domain-containing protein, JAC1, is necessary for chloroplast movement in Arabidopsis thaliana, to capture photosynthetic light efficiently under weak light conditions. Here, we performed crystallographic and functional analyses of the J-domain of JAC1. The crystal structure of the J-domain is quite similar to that of bovine auxilin, and possesses a similar positively charged surface, which probably forms the interface with the Hsp70 chaperone. The mutation of the highly conserved HPD motif of the JAC1 J-domain abrogated the chloroplast photorelocation response. These results suggest that the requirement of JAC1 in chloroplast photorelocation movement is attributable to the J-domain's cochaperone activity.
authors.affiliation: Division of Structural Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Takano
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Suetsugu
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Wada
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kohda
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D034021:Auxilins / Q000235:genetics / Q000378:metabolism*; D002736:Chloroplasts / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D054730:Protein Interaction Domains and Motifs; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
chemical_list: D029681:Arabidopsis Proteins; D034021:Auxilins; C518917:F9E10.5 protein, Arabidopsis