title: Inhibition of mRNA deadenylation by the nuclear cap binding complex (CBC).
abstract: Poly(A)-specific ribonuclease (PARN) is a cap-interacting and poly(A)-specific 3'-exoribonuclease. Here we have investigated how the cap binding complex (CBC) affects human PARN activity. We showed that CBC, via its 80-kDa subunit (CBP80), inhibited PARN, suggesting that CBC can regulate mRNA deadenylation. The CBC-mediated inhibition of PARN was cap-independent, and in keeping with this, the CBP80 subunit alone inhibited PARN. Our data suggested a new function for CBC, identified CBC as a potential regulator of PARN, and emphasized the importance of communication between the two extreme ends of the mRNA as a key strategy to regulate mRNA degradation. Based on our data, we have proposed a model for CBC-mediated regulation of PARN, which relies on an interaction between CBP80 and PARN. Association of CBC with PARN might have importance in the regulated recruitment of PARN to the nonsense-mediated decay pathway during the pioneer round of translation.
authors.affiliation: Department of Cell and Molecular Biology, Uppsala University, Sweden.
authors.forename: Nikolaos A A
authors.initials: NA
authors.lastname: Balatsos
authors.forename: Per
authors.initials: P
authors.lastname: Nilsson
authors.forename: Catherine
authors.initials: C
authors.lastname: Mazza
authors.forename: Stephen
authors.initials: S
authors.lastname: Cusack
authors.forename: Anders
authors.initials: A
authors.lastname: Virtanen
mesh_terms: D005095:Exoribonucleases / Q000037:antagonists & inhibitors* / Q000502:physiology; D006801:Humans; D039502:Nuclear Cap-Binding Protein Complex / Q000502:physiology*; D026723:Polyadenylation; D021122:Protein Subunits; D012315:RNA Caps / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism*
chemical_list: D005095:Exoribonucleases; D039502:Nuclear Cap-Binding Protein Complex; D021122:Protein Subunits; D012315:RNA Caps; D012333:RNA, Messenger