Searching for novel cell cycle regulators in Trypanosoma brucei with an RNA interference screen

<b>Background</b><br /> The protozoan parasite, Trypanosoma brucei, is spread by the tsetse fly and causes Human African Trypanosomiasis. Its cell cycle is complex and not fully understood at the molecular level. The T. brucei genome contains over 6000 protein coding genes with >50% having no predicted function. A small scale RNA interference (RNAi) screen was carried out in Trypanosoma brucei to evaluate the prospects for identifying novel cycle regulators.<p></p> <b>Results</b><br /> Procyclic form T. brucei were transfected with a genomic RNAi library and 204 clones isolated. However, only 76 RNAi clones were found to target a protein coding gene of potential interest. These clones were screened for defects in proliferation and cell cycle progression following RNAi induction. Sixteen clones exhibited proliferation defects upon RNAi induction, with eight clones displaying potential cell cycle defects. To confirm the phenotypes, new RNAi cell lines were generated and characterised for five genes targeted in these clones. While we confirmed that the targeted genes are essential for proliferation, we were unable to unambiguously classify them as cell cycle regulators.<p></p> <b>Conclusion</b><br /> Our study identified genes essential for proliferation, but did not, as hoped, identify novel cell cycle regulators. Screening of the RNAi library for essential genes was extremely labour-intensive, which was compounded by the suboptimal quality of the library. For such a screening method to be viable for a large scale or genome wide screen, a new, significantly improved RNAi library will be required, and automated phenotyping approaches will need to be incorporated.<p></p&gt

The Cry48Aa-Cry49Aa binary toxin from Bacillus sphaericus exhibits highly restricted target specificity.

Made available in DSpace on 2018-06-11T17:31:15Z (GMT). No. of bitstreams: 1 SP19713ID31176.pdf: 241478 bytes, checksum: f1bd6ea878cd02d7e5b55d4342f82a1f (MD5) Previous issue date: 2009-03-13bitstream/item/178424/1/SP-19713-ID-31176.pd

A case of Muir-Torre syndrome associated with mucinous hepatic cholangiocarcinoma and a novel germline mutation of the MSH2 gene

Muir-Torre syndrome (MTS) is a rare cancer-predisposing syndrome that is autosomal dominantly inherited and characterized by the development of sebaceous skin lesions (adenomas, epitheliomas, basaliomas and carcinomas). These lesions are typically associated with tumors that belong to the spectrum of hereditary nonpolyposis colorectal cancer (HNPCC) (i.e. tumors of the colorectum, endometrium, stomach or ovary). Biliary malignancy in association with MTS has only rarely been reported. We report a case of Muir-Torre syndrome associated with intrahepatic cholangiocarcinoma, a location not previously described, and associated with a novel missense mutation of the MSH2 gene (c.2026T>C), predicted to disrupt the function of the gen

Growth and phosphorus absorption by common bean 'Xodó' genotype under effect of glyphosate reduced rates.

Avaliou-se o efeito de subdoses de glyphosate no crescimento e na absorção de fósforo (P) pelo feijoeiro comum (Phaseolus vulgaris L.) cv. Xodó. O experimento foi conduzido em esquema fatorial 4 x 2 em blocos casualizados com quatro repetições, sendo o primeiro fator constituído pelas subdoses de 0; 4,32; 8,64 e 12,96 g ha-1 de equivalente ácido (e.a.) de glyphosate e o segundo fator constituído por doses de P no solo (50 e 250 mg dm-3). Avaliações foram realizadas 30 dias após a aplicação do glyphosate (DAA). A subdose de 12,96 g ha-1 estimulou o crescimento do feijoeiro comum cv. Xodó, assim como aumentou o teor de P no ramo e o conteúdo de P na parte aérea das plantas

Cholesterol oxidase effects on reproduction and embryonic development of the cotton boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae).

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Acute toxicity and cytotoxicity of Bacillus thuringiensis and Bacillus sphaericus strains on fish and mouse bone marrow.

Made available in DSpace on 2018-06-11T17:31:26Z (GMT). No. of bitstreams: 1 SP19703ID31175.pdf: 199147 bytes, checksum: 639b74490a905c882b2db6f70e918560 (MD5) Previous issue date: 2009-03-12bitstream/item/178426/1/SP-19703-ID-31175.pd