Obtenção de uma nova proteína recombinante componente do complexo telemérico LAGT1 de Leishmania Amazonensis

• Autor(a) principal: Souza, Bárbara Moraes [UNESP]
• Data de Publicação: 2013
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/121397
• topic: Leishmaniose; Leishmania; Telômero; Calmodulina; Proteínas de ligação a Telômeros; Leishmaniasis

Among the Leishmania genus are the causative agents of leishmaniasis, a medical important disease that presents a large spectrum of clinical presentations. The protozoa nuclear genome has 70Mb distributed in 34-36 chromosomes. Telomeres of L. amazonensis, one of the main ethiologic agents of cutaneous leishmaniais in the Americas, is composed by the conserved repetitive sequence 5'-TTAGGG-3', which presents in vitro and in vivo protein:DNA complexes, called LaGT1 - 3. The proteins LaRbp38 and LaRPA -1 compose respectively, LaGT2 and LaGT3 complexes. However, the protein component of LaGT1 (~15kDa) was not characterized and was the main goal of this study. Previous results showed that the component of LaGT1 complex is the most abundant and specific for single-stranded telomeric G-rich, remained associated with telomeres even under high salt concentrations and temperature variations. The purification of the protein component of the complex and subsequent sequencing analysis de novo using mass spectrometry, resulted in a sequence annotated as putative calmodulin, which gene that encodes is in three in tandem copies (LmjF09.0910, LmjF09.0920 and LmjF09.0930) in the genome of L. Major. The identity sequence of the parasite gene with other calmodulins or calcium ligands proteins, carrying the conserved calcium binding domain (EF-hand), indicates that this may be related to some function in a scenario involving the parasite calcium telomeric context. Here we emphasize that a protein with EF-hand domain, the KIP (DNA-dependent protein kinase), was described as part of the human telomeric complex by its interaction with telomerase. Based on this information, the protein component of LaGT1 can be considered a new protein in the parasite, which may represent in the future a specific target for anti-parasitic drugs. Thus, this proposal was aimed at cloning the gene that encodes the possibly component of LaGT1 using expression plasmid bacterial system. The ...