Conserved role for 14-3-3 epsilon downstream of type I TGF beta receptors

Schistosoma mansoni receptor kinase-1 (SmRK1) is a divergent type I transfo rming growth factor beta (TGF beta) receptor on the surface of adult parasi tes. Using the intracellular domain of SmRK1 as bait in a yeast two-hybrid screen ne identified an interaction with S. mansoni 14-3-3 epsilon. The int eraction which is phosphorylation-dependent is not specific to schistosomes since 14-3-3 epsilon also binds to T beta RI, the human type I TGF beta re ceptor. 14-3-3 epsilon enhances TGF beta -mediated signaling by T beta RI a nd is the first T beta RI-interacting non-Smad protein identified that posi tively regulates this receptor, The interaction of 14-3-3 epsilon with schi stosome and human T beta RI suggests a conserved, but previously unapprecia ted, role for this protein in TGF beta signaling pathways. (C) 2001 Federat ion of European Biochemical Societies. Published by Elsevier Science B.V. A ll rights reserved.