Expressão gênica em bibliotecas de cDNA de pele de bovinos F2 (Holandês × Gir) infestados com o carrapato Riphicephalus (Boophilus) microplus

• Ano de defesa: 2009
• Autor(a) principal: Nascimento, Carlos Souza do
• Orientador(a): Guimarães, Simone Eliza Facioni
• Banca de defesa: Guimarães, Marta Fonseca Martins , Braccini Neto, José , Carneiro, Paulo Luiz Souza
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Zootecnia
• Departamento: Genética e Melhoramento de Animais Domésticos; Nutrição e Alimentação Animal; Pastagens e Forragicul
• País: BR
• Palavras-chave em Português: Step; QRE-OCR; Pele; Riphicephalus (Boophilus) microplus
• Palavras-chave em Inglês: Step; QRE-OCR; Skin; Riphicephalus (Boophilus) microplus
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::GENETICA E MELHORAMENTO DOS ANIMAIS DOMESTICOS
• Link de acesso: http://locus.ufv.br/handle/123456789/1721

It is known that resistance to cattle tick Riphicephalus (Boophilus) microplus is inheritable and are primarily associated with zebu animals (Bos indicus), although also present at lower levels in some breed taurine (B. taurus). The elucidation of genetic resistance is one of the most promising factors to reduce production losses and to reduce the cost of this parasite control in livestock tropical bovine. In order to characterize the functional genes in involved resistance / susceptibility of cattle to ticks, two of cDNA libraries were constructed from skin of F2 animals (Holstein × Gyr) resistant and susceptible infested with larvae of R. microplus. We sequenced 4,070 Expressed sequence tags (ESTs) from skin F2 cattle (Holstein × Gyr) infested with the tick R. microplus. From total of generated ESTs, 2,700 high quality sequences from two cDNA libraries were obtained. Clustering results generated a nonredundant set of 1.292 unique sequences. About 790 of the sequences shared significant similarity with known protein sequences and 502 of these gave no similarity to protein sequences deposited on non-redundant (nr) protein database (NCBI - National Center of Biotechnology Information). The functional profile analysis of transcripts indicated 54 Gene Ontology terms (GO-terms) significant (P<0.01) over represented on res and sus datasets in relation to B. taurus genome. We also estimated the percentage of genes presents on ESTs dataset. The gene capture predictions were 49% (RES) e 40% (SUS). Realtime polymerase chain reaction was used to determine the gene expression level to four genes identified on cDNA libraries. The relative expression of the S100A7, TPT1, TRV6 and CST6 genes was 2.01 (±0.6), 1.32 (±0.9), 1.53 (±1.2), (2.03±0.6), respectively. Our findings show that these genes were differentially expressed (P=0.001) in skin lesions from susceptible animals. However, the increased expression of these genes does not appear to confer protection against to infestation with ticks. To date, no study of functional genomics to crossbreed animals (Holstein x Gyr) has been reported. The transcripts generated in this study can contribute substantially to a better understanding of the functional genomics of host-parasite interaction in this tissue.