title: An siRNA ribonucleoprotein is found associated with polyribosomes in Trypanosoma brucei.
abstract: Genetic interference by double-stranded RNA (dsRNA) or RNA interference (RNAi) triggers the sequence-specific degradation of cellular transcripts. The mediators of mRNA degradation are small interfering RNAs (siRNAs). Here, we report that in Trypanosoma brucei, 10%-20% of siRNAs cosediment with polyribosomes. Preventing the assembly of ribosomes on mRNAs results in a concomitant decrease of siRNAs sedimenting as high-molecular-weight complexes. We further provide evidence that siRNAs are associated with translating ribosomes and that this association is mediated by a 70-kD ribonucleoprotein complex.
authors.affiliation: Department of Internal Medicine, Yale University Medical School, New Haven, Connecticut 06520-8022, USA.
authors.forename: Appolinaire
authors.initials: A
authors.lastname: Djikeng
authors.forename: Huafang
authors.initials: H
authors.lastname: Shi
authors.forename: Christian
authors.initials: C
authors.lastname: Tschudi
authors.forename: Shuiyuan
authors.initials: S
authors.lastname: Shen
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Ullu
mesh_terms: D000818:Animals; D008970:Molecular Weight; D011132:Polyribosomes / Q000235:genetics*; D012330:RNA, Double-Stranded / Q000235:genetics; D016053:RNA, Protozoan / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics* / Q000302:isolation & purification; D012261:Ribonucleoproteins / Q000235:genetics; D014346:Trypanosoma brucei brucei / Q000235:genetics*
chemical_list: D012330:RNA, Double-Stranded; D016053:RNA, Protozoan; D034741:RNA, Small Interfering; D012261:Ribonucleoproteins