Abstract:
:The technique of RNA interference (RNAi) is exceedingly useful for knocking down the expression of a specific mRNA in African trypanosomes and other organisms for the purpose of examining the function of its gene. However, when we attempted to apply RNAi in the Latin American trypanosome, Trypanosoma cruzi, to diminish expression of mRNA encoding the surface protein amastin, we found that the amastin double-stranded RNA (dsRNA) was not efficiently degraded in either epimastigotes or amastigotes, and the level of amastin mRNA remained unchanged. We generated a strain of T. cruzi CL-Brener in which the T7 promoter and tetracycline operator could be used to maximize tetracycline-regulated dsRNA synthesis and constructed plasmids that direct dsRNA against four different T. cruzi endogenous genes (encoding beta-tubulin, GP72 (flagellar adhesion protein), ribosomal protein P0 and amastin) and an exogenously added gene (GFP; green fluorescent protein). After either stable or transient transfection of these plasmids into T. cruzi, the expected RNAi phenotype was not observed for any of the five genes, although the T. cruzi beta-tubulin RNAi plasmid did give the expected FAT cell phenotype in the African trypanosome, Trypanosoma brucei. These data indicate that, similar to Leishmania, T. cruzi lacks one or more components necessary for the RNAi pathway and that these components will need to be engineered into T. cruzi, or compensated for, before RNAi can be used to study gene function in this organism.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
DaRocha WD,Otsu K,Teixeira SM,Donelson JEdoi
10.1016/j.molbiopara.2003.10.005subject
Has Abstractpub_date
2004-02-01 00:00:00pages
175-86issue
2eissn
0166-6851issn
1872-9428pii
S0166685103003025journal_volume
133pub_type
杂志文章abstract::In trypanosomes, trans-splicing is a major essential RNA-processing mechanism that involves the addition of a spliced leader sequence to all mRNAs from a small RNA species, known as the spliced leader RNA (SL RNA). SL RNA maturation is poorly understood and it is not clear where assembly with Sm proteins takes place. ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2006.07.004
更新日期:2006-12-01 00:00:00
abstract::Peptidomimetic inhibitors of mammalian zinc metalloproteases have been tested as potential agents for intervention in disease caused by kinetoplastid protozoa. Certain metalloprotease inhibitors were able to inhibit the release of variant surface glycoprotein from cultured transgenic procyclic Trypanosoma brucei, conf...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(01)00244-4
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journal_title:Molecular and biochemical parasitology
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doi:10.1016/0166-6851(95)02533-2
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abstract::Microsporidia are highly adapted eukaryotic intracellular parasites that infect a variety of animals. Microsporidia contain no recognisable mitochondrion, but recently have been shown to have evolved from fungi and to possess heat shock protein genes derived from mitochondria. These findings make it clear that microsp...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(01)00356-5
更新日期:2001-10-01 00:00:00
abstract::Plasmodium falciparum invades human erythrocytes by redundant pathways. Unlike Plasmodium vivax that has one Duffy Binding-Like (DBL) receptor, P. falciparum has four members of the DBL receptor family. Furthermore, one of these DBL genes, BAEBL, has polymorphisms at four amino acids in region II; each polymorphism bi...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2009.06.006
更新日期:2009-11-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90178-m
更新日期:1992-12-01 00:00:00
abstract::We have determined the sequence of a cDNA (Tt34c1) encoding a Trypanosoma cruzi trypomastigote stage-specific 85-kDa surface glycoprotein (gp85). Within the peptide sequence of Tt34c1 are two 8-amino acid motifs, Ser-X-Asp-X-Gly-X-Thr-Trp, that are characteristic of bacterial neuraminidases. Analysis of the Tt34c1 seq...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:1994-08-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2006.02.014
更新日期:2006-06-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:1996-12-20 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(00)00371-6
更新日期:2001-02-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(88)90073-4
更新日期:1988-06-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(93)90048-3
更新日期:1993-04-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.02.009
更新日期:2012-06-01 00:00:00
abstract::Theileria annulata is a tick-transmitted protozoan that causes tropical theileriosis, an often fatal leukoproliferative disorder of cattle. To characterize and identify parasite proteins suitable as diagnostic antigens and/or vaccine candidates, a cDNA clone encoding a macroschizont stage protein was isolated and char...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:2002-04-09 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90049-p
更新日期:1992-06-01 00:00:00
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journal_title:Molecular and biochemical parasitology
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更新日期:2001-09-03 00:00:00
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journal_title:Molecular and biochemical parasitology
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
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更新日期:1996-02-01 00:00:00
abstract::Cryptosporidiosis is an obligate intracellular pathogen causing diarrhea. Merozoite egress is essential for infection to spread between host cells. However, the mechanisms of egress have yet to be defined. We hypothesized that Cyclic GMP-Dependent Protein Kinase G (PKG) may be involved in Cryptosporidium egress. In th...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:2020-05-01 00:00:00
abstract::Theileria annulata is an important pathogen of cattle in the tropics. The gene sequence of a sporozoite surface antigen (SPAG-1) is reported. Data is also presented demonstrating that SPAG-1 is synthesised as a large precursor. This antigen, which is a candidate for inclusion in a subunit vaccine, shows a remarkable d...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90012-9
更新日期:1992-07-01 00:00:00
abstract::The merozoite surface protein-1 of the human malaria parasite Plasmodium falciparum undergoes an extracellular proteolytic cleavage (secondary processing) intrinsic to successful erythrocyte invasion. In the T9/96 clone of P. falciparum the protease responsible has been characterised as a membrane-associated, calcium-...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(93)90182-w
更新日期:1993-11-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:2010-08-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:1986-01-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:2014-12-01 00:00:00
abstract::Trypanosoma brucei harbors a unique multifunctional RNA polymerase (pol) I which transcribes, in addition to ribosomal RNA genes, the gene units encoding the major cell surface antigens variant surface glycoprotein and procyclin. In consequence, this RNA pol I is recruited to three structurally different types of prom...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:2006-09-01 00:00:00
abstract::Giardia duodenalis is a widespread parasite of mammalian species, including humans. Due to its invariant morphology, investigation on aspects such as host specificity and transmission patterns requires a direct genetic characterization of cysts/trophozoites from host samples. A number of molecular assays have been dev...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
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更新日期:2008-08-01 00:00:00
abstract::The nucleotide sequence of a gene encoding a 35-kDa thiol protease of the parasitic nematode Haemonchus contortus has been determined. The gene, designated AC-2, shares 97% nucleotide sequence identity and 98% amino acid identity with previously characterized AC-1 cDNAs encoding the thiol protease. The AC-2 gene spans...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:1990-12-01 00:00:00