Arabidopsis F-BOX STRESS INDUCED (FBS) proteins have distinct subcellular interaction patterns with 14-3-3 proteins.

F-BOX STRESS INDUCED (FBS) proteins are substrate adaptors in SCF-type E3 ubiquitin ligases that regulate plant development and stress responses. Arabidopsis thaliana FBS1 (AT1G61340) interacts with multiple 14-3-3 proteins, but it is unknown whether other FBS family members share these interactions. Bimolecular fluorescence complementation (BiFC) assays in Nicotiana benthamiana showed that all four FBS proteins interact with multiple 14-3-3 proteins in vivo. However, FBS1 interactions were restricted to the nucleus, whereas FBS2 - FBS4 (AT4G21510, AT4G05010, AT4G35930) interactions were detected in both the nucleus and cytosol. These findings indicate conserved 14-3-3 interactions within the FBS family, but suggest functional divergence in subcellular interaction profiles.