Hypermethylated-capped selenoprotein mRNAs in mammals.

ABSTRACT: Mammalian mRNAs are generated by complex and coordinated biogenesis pathways and acquire 5'-end m(7)G caps that play fundamental roles in processing and translation. Here we show that several selenoprotein mRNAs are not recognized efficiently by translation initiation factor eIF4E because they bear a hypermethylated cap. This cap modification is acquired via a 5'-end maturation pathway similar to that of the small nucle(ol)ar RNAs (sn- and snoRNAs). Our findings also establish that the trimethylguanosine synthase 1 (Tgs1) interacts with selenoprotein mRNAs for cap hypermethylation and that assembly chaperones and core proteins devoted to sn- and snoRNP maturation contribute to recruiting Tgs1 to selenoprotein mRNPs. We further demonstrate that the hypermethylated-capped selenoprotein mRNAs

SUBMITTER: Wurth L 

PROVIDER: S-EPMC4117793 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature