14-3-3 and its possible role in co-ordinating multiple signalling pathways

Members of the 14-3-3 family are homo- and heterodimeric proteins mediating interaction between diverse components of many biological activities. The role of these proteins has been unclear for some time, but they are now gaining acceptance as a novel type of chaperone protein that modulates interactions between components of signal-transduction pathways. It is becoming apparent from recent studies that phosphorylation of the binding partner and possibly also the 14-3-3 proteins themselves is important in regulating these interactions. Analysis of the major sites of phosphorylation in Raf has led to the identification of a novel sequence motif, R(S)X(1,2)S(P)X(P), that may represent a conserved interaction site for 14-3-3-binding proteins.