title: Interaction specificity of Arabidopsis 14-3-3 proteins with phototropin receptor kinases.
abstract: Phototropin receptor kinases play an important role in optimising plant growth in response to blue light. Much is known regarding their photochemical reactivity, yet little progress has been made to identify downstream signalling components. Here, we isolated several interacting proteins for Arabidopsis phototropin 1 (phot1) by yeast two-hybrid screening. These include members of the NPH3/RPT2 (NRL) protein family, proteins associated with vesicle trafficking, and the 14-3-3 lambda (lambda) isoform from Arabidopsis. 14-3-3lambda and phot1 were found to colocalise and interact in vivo. Moreover, 14-3-3 binding to phot1 was limited to non-epsilon 14-3-3 isoforms and was dependent on key sites of receptor autophosphorylation. No 14-3-3 binding was detected for Arabidopsis phot2, suggesting that 14-3-3 proteins are specific to phot1 signalling.
authors.affiliation: Division of Molecular and Cellular Biology, Faculty of Biomedical and Life Sciences, University of Glasgow, Glasgow, UK.
authors.forename: Stuart
authors.initials: S
authors.lastname: Sullivan
authors.forename: Catriona E
authors.initials: CE
authors.lastname: Thomson
authors.forename: Eirini
authors.initials: E
authors.lastname: Kaiserli
authors.forename: John M
authors.initials: JM
authors.lastname: Christie
mesh_terms: D048948:14-3-3 Proteins / Q000737:chemistry / Q000378:metabolism; D017360:Arabidopsis / Q000201:enzymology / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism; D010766:Phosphorylation; D010802:Phylogeny; D017346:Protein Serine-Threonine Kinases; D016415:Sequence Alignment; D015398:Signal Transduction; D013379:Substrate Specificity; D020798:Two-Hybrid System Techniques
chemical_list: D048948:14-3-3 Proteins; D029681:Arabidopsis Proteins; C103646:NPH1 protein, Arabidopsis; D010750:Phosphoproteins; C423903:PHOT2 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases; C117576:AFT1 protein, Arabidopsis