title: Isoform-specific subcellular localization among 14-3-3 proteins in Arabidopsis seems to be driven by client interactions.
abstract: In most higher eukaryotes, the predominantly phosphoprotein-binding 14-3-3 proteins are the products of a multigene family, with many organisms having 10 or more family members. However, current models for 14-3-3/phosphopeptide interactions suggest that there is little specificity among 14-3-3s for diverse phosphopeptide clients. Therefore, the existence of sequence diversity among 14-3-3s within a single organism begs questions regarding the in vivo specificities of the interactions between the various 14-3-3s and their clients. Chief among those questions is, Do the different 14-3-3 isoforms interact with different clients within the same cell? Although the members of the Arabidopsis 14-3-3 family of proteins typically contain highly conserved regions of sequence, they also display distinctive variability with deep evolutionary roots. In the current study, a survey of several Arabidopsis 14-3-3/GFP fusions revealed that 14-3-3s demonstrate distinct and differential patterns of subcellular distribution, by using trichomes and stomate guard cells as in vivo experimental cellular contexts. The effects of client interaction on 14-3-3 localization were further analyzed by disrupting the partnering with peptide and chemical agents. Results indicate that 14-3-3 localization is both isoform specific and highly dependent upon interaction with cellular clients.
authors.affiliation: Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of Florida, Gainesville, 32611, USA.
authors.forename: Anna-Lisa
authors.initials: AL
authors.lastname: Paul
authors.forename: Paul C
authors.initials: PC
authors.lastname: Sehnke
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Ferl
mesh_terms: D048948:14-3-3 Proteins / Q000235:genetics / Q000378:metabolism*; D000620:Aminoimidazole Carboxamide / Q000031:analogs & derivatives / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012265:Ribonucleotides / Q000378:metabolism
chemical_list: D048948:14-3-3 Proteins; D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins; D012265:Ribonucleotides; D000620:Aminoimidazole Carboxamide; C031143:AICA ribonucleotide