Phosphorylation-independent interaction between 14-3-3 and exoenzyme S: from structure to pathogenesis.

14-3-3 proteins are required for the inhibition of Ras by exoenzyme S.

14-3-3 proteins play a regulatory role and participate in both signal transduction and checkpoint control pathways. 14-3-3 proteins bind phosphoserine ligands, such as Raf-1 kinase and Bad, by recognizing the phosphorylated consensus motif, Arg-Ser-Xaa-pSer-Xaa-Pro (where 'Xaa' represents 'any residue', and 'pSer' is 'phosphoserine'). However, 14-3-3 proteins must bind unphosphorylated ligands,...

Exoenzyme S of Pseudomonas aeruginosa: cellular targets and interaction with 14-3-3

Phosphorylation-independent interaction between 14-3-3 protein and the plant plasma membrane H+-ATPase.

14-3-3 proteins interact with a novel phosphothreonine motif (Y(946)pTV) at the extreme C-terminal end of the plant plasma membrane H(+)-ATPase molecule. Phosphorylation-independent binding of 14-3-3 protein to the YTV motif can be induced by the fungal phytotoxin fusicoccin. The molecular basis for the phosphorylation-independent interaction between 14-3-3 and H(+)-ATPase in the presence of fu...

Structural basis for protein-protein interactions in the 14-3-3 protein family.

The seven members of the human 14-3-3 protein family regulate a diverse range of cell signaling pathways by formation of protein-protein complexes with signaling proteins that contain phosphorylated Ser/Thr residues within specific sequence motifs. Previously, crystal structures of three 14-3-3 isoforms (zeta, sigma, and tau) have been reported, with structural data for two isoforms deposited i...

The eukaryotic host factor that activates exoenzyme S of Pseudomonas aeruginosa is a member of the 14-3-3 protein family.

Exoenzyme S (ExoS), which has been implicated as a virulence factor of Pseudomonas aeruginosa, catalyzes transfer of the ADP-ribose moiety of NAD+ to many eukaryotic cellular proteins. Its preferred substrates include Ras and several other 21- to 25-kDa GTP-binding proteins. ExoS absolutely requires a ubiquitous eukaryotic protein factor, termed FAS (factor activating ExoS), for enzymatic activ...