The Trypanosoma brucei La protein is a candidate poly(U) shield that impacts spliced leader RNA maturation and tRNA intron removal.

摘要: By virtue of its preferential binding to poly(U) tails on small RNA precursors and nuclear localisation motif, the La protein has been implicated for a role in stabilisation retention processing intermediates variety RNAs eukaryotic cells. As universal substrate trans-splicing, spliced leader is transcribed as precursor with just such tail. was targeted selective knockdown by inducible interference Trypanosoma brucei. Of three strategies employed, p2T7-177 vector most effective reducing both mRNA well itself from induced In relative absence T. brucei cells were not viable, contrast gene knockouts yeast. A potential substrates examined under induction, including RNA, associated U1, U2, U4, U6 RNAs, 5S ribosomal U3 nucleolar tRNATyr. None these molecules showed significant variance size or abundance their mature forms, although discrete subset appear tRNATyr intron splicing depletion conditions. 5'-end methylation U1 unaffected. The immediate cause lethality apparent, but may represent cumulative effect multiple defects other unidentified substrates. This study indicates that essential maturation does rule out presence an alternative pathway could compensate normally-associated protein.