title: Long double-stranded RNA produces specific gene downregulation in Giardia lamblia.
abstract: In many eukaryotes, the introduction of double-stranded RNA (dsRNA) into cells triggers the degradation of mRNAs through a post-transcriptional gene-silencing mechanism called RNA interference or RNAi. In the present study, we found that endogenous long-dsRNA was substantially more effective at producing interference than endogenous, or exogenous, short-dsRNA expression in Giardia lamblia . The effects of this interference were not evident in the highly expressed protein tubulin or the stage-specific cyst wall protein 2. However, long-dsRNA caused potent and specific interference in the medium subunits of adaptins, the RNA-dependent RNA polymerase, and the exogenous green fluorescence protein. Our results suggest that the ability of dsRNA antisense to inhibit the expression of these specific types of proteins is indicative of a gene-specific mechanism.
authors.affiliation: Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET, Friuli 2434, Córdoba, Argentina.
authors.forename: Maria R
authors.initials: MR
authors.lastname: Rivero
authors.forename: Liudmila
authors.initials: L
authors.lastname: Kulakova
authors.forename: Maria C
authors.initials: MC
authors.lastname: Touz
mesh_terms: D034001:Adaptor Protein Complex Subunits / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation / Q000235:genetics*; D000091342:Endoplasmic Reticulum Chaperone BiP; D019085:Fluorescent Antibody Technique, Direct; D019084:Fluorescent Antibody Technique, Indirect; D005786:Gene Expression Regulation / Q000235:genetics; D016829:Giardia lamblia / Q000235:genetics* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference / Q000502:physiology*; D012330:RNA, Double-Stranded / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics / Q000378:metabolism; D014404:Tubulin / Q000235:genetics / Q000378:metabolism
chemical_list: D034001:Adaptor Protein Complex Subunits; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins; D015800:Protozoan Proteins; D012330:RNA, Double-Stranded; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D014404:Tubulin; D049452:Green Fluorescent Proteins; D012324:RNA-Dependent RNA Polymerase