Members of the 14-3-3 family of proteins are highly conserved proteins, localized in neurons, and are axonally transported to the nerve terminals. They are also present, at lower levels, in various other eukaryotic tissues. 14-3-3 proteins appear to play important roles in a variety of signal transduction pathways, including those involved in cell cycle regulation and cell survival. Because 14-3-3 proteins bind to specific phosphoserine-containing sequences they are likely to have an important role in signaling pathways mediated by serine/threonine protein kinases. Evidence indicates 14-3-3 is required for Raf 1 kinase activity and phosphorylation among many other functions.