2009
Distinct and overlapping roles for two Dicer-like proteins in the RNA interference pathways of the ancient eukaryote Trypanosoma brucei
Patrick KL, Shi H, Kolev NG, Ersfeld K, Tschudi C, Ullu E. Distinct and overlapping roles for two Dicer-like proteins in the RNA interference pathways of the ancient eukaryote Trypanosoma brucei. Proceedings Of The National Academy Of Sciences Of The United States Of America 2009, 106: 17933-17938. PMID: 19815526, PMCID: PMC2764927, DOI: 10.1073/pnas.0907766106.Peer-Reviewed Original ResearchConceptsDicer-like enzymesRNA interferenceRNAi pathwayBiogenesis of siRNAsDicer-like proteinsNuclear RNAi pathwaySingle Argonaute proteinEnd modificationReverse genetic analysisRNAi-deficient cellsRNA interference (RNAi) pathwayWild-type cellsAncient eukaryotesArgonaute proteinsRNAi responseAncient traitRepeat transcriptsInterference pathwayCytoplasmic proteinsImportant human pathogenTrypanosoma bruceiGenetic analysisRNAi triggersFunctional analysisIntermediate transcripts
2001
RNA interference in Trypanosoma brucei: cloning of small interfering RNAs provides evidence for retroposon-derived 24-26-nucleotide RNAs.
Djikeng A, Shi H, Tschudi C, Ullu E. RNA interference in Trypanosoma brucei: cloning of small interfering RNAs provides evidence for retroposon-derived 24-26-nucleotide RNAs. RNA 2001, 7: 1522-30. PMID: 11720282, PMCID: PMC1370195.Peer-Reviewed Original ResearchConceptsDouble-stranded RNARNA interferenceGene-specific double-stranded RNAHigh-speed pellet fractionStrand-specific probesSmall interfering RNAsTarget RNA degradationDsRNA resultsHousekeeping functionsTrypanosoma bruceiRNA degradationCellular RNAInterfering RNAsNorthern hybridizationWeight complexesSequence analysisHigh-speed pelletRNALong fragmentSiRNAsPellet fractionEnrichment strategyCloningSupernatant fractionFragmentsUnusual diversity in α-amanitin sensitivity of RNA polymerases in trichomonads
Vaňáčová Š, Tachezy J, Ullu E, Tschudi C. Unusual diversity in α-amanitin sensitivity of RNA polymerases in trichomonads. Molecular And Biochemical Parasitology 2001, 115: 239-247. PMID: 11420110, DOI: 10.1016/s0166-6851(01)00294-8.Peer-Reviewed Original ResearchConceptsUnusual diversityResistant RNA polymerase IIProtein coding genesParasitic protist Trichomonas vaginalisRNA polymerase IIAlpha-amanitin sensitivityProtist Trichomonas vaginalisGenus-specific patternsTritrichomonas foetusLysolecithin-permeabilized cellsUnicellular eukaryotesCoding genesPolymerase IIRNAP IIRNAP IIIRNA polymeraseTrichomonad speciesAlpha-amanitinT. vaginalisRNA synthesisΑ-amanitin sensitivityDiversityTrichomonadsRelated groupsEukaryotesCharacterization of a candidate Trypanosoma brucei U1 small nuclear RNA gene
Djikeng A, Ferreira L, D'Angelo M, Dolezal P, Lamb T, Murta S, Triggs V, Ulbert S, Villarino A, Renzi S, Ullu E, Tschudi C. Characterization of a candidate Trypanosoma brucei U1 small nuclear RNA gene. Molecular And Biochemical Parasitology 2001, 113: 109-115. PMID: 11254959, DOI: 10.1016/s0166-6851(00)00384-4.Peer-Reviewed Original Research
2000
Determinants for cap trimethylation of the U2 small nuclear RNA are not conserved between Trypanosoma brucei and higher eukaryotic organisms
Günzl A, Bindereif A, Ullu E, Tschudi C. Determinants for cap trimethylation of the U2 small nuclear RNA are not conserved between Trypanosoma brucei and higher eukaryotic organisms. Nucleic Acids Research 2000, 28: 3702-3709. PMID: 11000261, PMCID: PMC110770, DOI: 10.1093/nar/28.19.3702.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBase SequenceBinding SitesCell LineConserved SequenceGuanosineMethylationMolecular Sequence DataMutationNucleic Acid ConformationPrecipitin TestsPromoter Regions, GeneticProtein BindingRegulatory Sequences, Nucleic AcidRibonucleoproteins, Small NuclearRNA CapsRNA, ProtozoanRNA, Small NuclearTransfectionTrypanosoma brucei bruceiConceptsCap trimethylationRibonucleoprotein particleEukaryotic organismsU2 snRNATrypanosoma bruceiU2 small nuclear RNA genesCap structureProtist parasite Trypanosoma bruceiSmall nuclear RNA genesCommon proteinsU2 small nuclear RNANuclear RNA genesHigher eukaryotic organismsRNA polymerase IIRNA polymerase IIISmall nuclear RNAMutant U2 snRNAsSet of proteinsParasite Trypanosoma bruceiSpliceosomal snRNPsRNP assemblyNuclear importPolymerase IIRNA genesSequence motifsCotranscriptional Cap 4 Formation on the Trypanosoma brucei Spliced Leader RNA*
Mair G, Ullu E, Tschudi C. Cotranscriptional Cap 4 Formation on the Trypanosoma brucei Spliced Leader RNA*. Journal Of Biological Chemistry 2000, 275: 28994-28999. PMID: 10880518, DOI: 10.1074/jbc.m004193200.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsRNA CapsRNA, ProtozoanRNA, Spliced LeaderTranscription, GeneticTrypanosoma brucei bruceiConceptsCap 4 structureSL RNAMRNA cap formationT. brucei cellsSpliced leader RNARNA cap structureSpliced leader sequenceTranscriptional arrestTrypanosomatid protozoaBrucei cellsLeader RNACap 4Cotranscriptional mechanismLeader sequenceTrypanosoma bruceiCap structureRNA transcriptsRibonucleoprotein formationAdenosine residuesPosition 117RNATranscriptsCap formationNucleotidesEukaryotesA new twist in trypanosome RNA metabolism: cis-splicing of pre-mRNA.
Mair G, Shi H, Li H, Djikeng A, Aviles H, Bishop J, Falcone F, Gavrilescu C, Montgomery J, Santori M, Stern L, Wang Z, Ullu E, Tschudi C. A new twist in trypanosome RNA metabolism: cis-splicing of pre-mRNA. RNA 2000, 6: 163-9. PMID: 10688355, PMCID: PMC1369902, DOI: 10.1017/s135583820099229x.Peer-Reviewed Original ResearchConceptsCis-spliced intronsSplice siteGT/AG ruleSmall intergenic regionAncient acquisitionGene arrangementTrypanosome genomeEukaryotic cellsRNA metabolismIntergenic regionIntron removalLeader sequenceTrypanosoma bruceiIntronsNucleotide positionsAG dinucleotideEuglena gracilisTrypanosoma cruziPolymerase geneIdentical positionsPoint mutationsRecent discoveryPAP mRNAGenesMRNA
1997
Structure of the Trypanosoma brucei U6 snRNA gene promoter
Nakaar V, Günzl A, Ullu E, Tschudi C. Structure of the Trypanosoma brucei U6 snRNA gene promoter. Molecular And Biochemical Parasitology 1997, 88: 13-23. PMID: 9274863, DOI: 10.1016/s0166-6851(97)00078-9.Peer-Reviewed Original ResearchConceptsU6 snRNA gene promoterSnRNA gene promotersB-boxGene promoterA boxSnRNA gene transcriptionInternal control regionRNA polymerase IIITRNA-like genesU6 transcriptionChromatin organizationTranscription extractRNA genesTranscription unitYeast SaccharomycesYeast systemControl regionPolymerase IIIStart siteGene transcriptionNucleotides upstreamPromoter elementsTrypanosoma bruceiIntragenic sequencesSaturation mutagenesisTranscription of the Trypanosoma brucei spliced leader RNA gene is dependent only on the presence of upstream regulatory elements
Günzl A, Ullu E, Dörner M, Fragoso S, Hoffmann K, Milner J, Morita Y, Nguu E, Vanacova S, Wünsch S, Dare A, Kwon H, Tschudi C. Transcription of the Trypanosoma brucei spliced leader RNA gene is dependent only on the presence of upstream regulatory elements. Molecular And Biochemical Parasitology 1997, 85: 67-76. PMID: 9108549, DOI: 10.1016/s0166-6851(96)02816-2.Peer-Reviewed Original Research
1995
Accurate Modification of the Trypanosome Spliced Leader Cap Structure in a Homologous Cell-free System (∗)
Ullu E, Tschudi C. Accurate Modification of the Trypanosome Spliced Leader Cap Structure in a Homologous Cell-free System (∗). Journal Of Biological Chemistry 1995, 270: 20365-20369. PMID: 7657609, DOI: 10.1074/jbc.270.35.20365.Peer-Reviewed Original ResearchConceptsSL RNACap structureCell-free systemRibonucleoprotein particleUnusual cap structureSpliced leader sequenceTrans-splicing activityHomologous cell-free systemRNA maturationTrypanosomatid protozoaNucleotide compositionC. fasciculataLeader sequenceTrypanosoma bruceiCell-free extractsT. bruceiT. cruziRNANucleotides 7Vitro reactionBruceiTwo-dimensional thin-layer chromatographyL. amazonensisLeishmania amazonensisCrithidia
1994
A common pyrimidine-rich motif governs trans-splicing and polyadenylation of tubulin polycistronic pre-mRNA in trypanosomes.
Matthews K, Tschudi C, Ullu E. A common pyrimidine-rich motif governs trans-splicing and polyadenylation of tubulin polycistronic pre-mRNA in trypanosomes. Genes & Development 1994, 8: 491-501. PMID: 7907303, DOI: 10.1101/gad.8.4.491.Peer-Reviewed Original Research
1993
2'-O-methyl RNA oligonucleotides identify two functional elements in the trypanosome spliced leader ribonucleoprotein particle
Ullu E, Tschudi C. 2'-O-methyl RNA oligonucleotides identify two functional elements in the trypanosome spliced leader ribonucleoprotein particle. Journal Of Biological Chemistry 1993, 268: 13068-13073. PMID: 8514747, DOI: 10.1016/s0021-9258(19)38620-x.Peer-Reviewed Original ResearchTemporal order of RNA-processing reactions in trypanosomes: rapid trans splicing precedes polyadenylation of newly synthesized tubulin transcripts.
Ullu E, Matthews K, Tschudi C. Temporal order of RNA-processing reactions in trypanosomes: rapid trans splicing precedes polyadenylation of newly synthesized tubulin transcripts. Molecular And Cellular Biology 1993, 13: 720-725. PMID: 8417363, PMCID: PMC358950, DOI: 10.1128/mcb.13.1.720.Peer-Reviewed Original ResearchConceptsRNA-processing reactionsTrans splicingPre-mRNASplice sitePolycistronic transcription unitsSplice acceptor siteTrypanosome genesMRNA biogenesisTranscription unitTrypanosome mRNAsLeader RNATubulin transcriptsSplicingAlpha-tubulinPolyadenylationMRNA synthesisAcceptor sitesTrypanosomesTemporal orderMRNABiogenesisGenesTranscriptsRNAOrganisms