Validation of genes identified by microarray which showed to be differentially expressed in the skin of cattle breed resistant (Nelore) or susceptible (Holandês) to ticks

• Grant number: 11/02725-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: August 01, 2011
• End date: February 28, 2013
• Field of knowledge: Biological Sciences - Immunology
• Principal Investigator: Beatriz Rossetti Ferreira
• Grantee: Nadia Caroline Sobrinho Gauna
• Host Institution: Escola de Enfermagem de Ribeirão Preto (EERP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Rhipicephalus (Boophilus) microplus ticks are considered one of the most important parasites of cattle in the world, causing major economic losses in livestock farming worldwide. They are widely distributed throughout the national territory, leading to anemia, cachexia and stress, that reduce the production of meat and milk; in addition to causing depreciation of leather by mechanical trauma due to its attachment and the transmission of various diseases. Using the technique of microarray, our group observed differences in the expression of several genes in the skin of nelore cattle (more resistant) or holandês (more susceptible) infested with ticks. Some of the differences were found were related to genes like tenascin, queratocan, type I collagen, osteoglicina, osteonectina, metalloproteinases and fibronectin, among others. Based on this identification, our aim in the present project is to study/understand better the corresponding genes to proteins: osteoglicina, queratocan and collagen type I alpha 1 during infestations with ticks. In this project we will make the validation of such differential expression by real time PCR and immunohistochemistry. The results may help to elucidate mechanisms by which the resistant animals can avoid heavy infestations with ticks, in addition to assisting in the development of biomarkers for use in programs of selective breeding of cattle and in the choice of candidate antigens for anti-tick vaccines. (AU)