Identification and characterization of proteins that interact with the carboxy terminus of poly(A)-binding protein and inhibit translation in vitro

摘要: Poly(A)-binding proteins (PABPs) are multifunctional that play important roles in mRNA stability and protein translation. Two cucumber (Cucumis sativus L.) proteins, PCI6 (PABP-CT-interacting) PCI243 were identified based on ability to interact with the carboxy terminus (CT) of PABP yeast two-hybrid vitro binding assays. share a conserved amino acid domain (SxLnpnApxFxP) common human PABP-CT interactors, Arabidopsis ERD15 (early-responsive dehydration). Deletion analysis point mutations indicate presence this is necessary for interaction, tests demonstrate it predictive interaction. Other plant possessing fall into two categories: small, acidic like PCI6, ERD15, larger neutral also include an RNA recognition motif. expressed range tissues, e.g., leaves, roots, stems flowers, follows diurnal pattern expression, increasing during light hours declining overnight. In wheat germ mouse ascites Krebs-2 translation systems, inhibited whereas non-interacting mutant, PCI6-23A, did not or had greatly reduced effect. The activity therefore, reminiscent PABP-interacting 2 (Paip2). These results novel interaction between several sharing SxLnpxApxFxP motif, possible implications translational regulation.