Genes PR5: caracterização molecular in silico de extração de DNA de plantas do semiárido para isolamento por PCR.

Abstract

The search for news antifungal PR-5 genes is interesting due to possible biotechnological applications in agricultural and health to control fungal diseases. In this context, Caatinga plants represent a rich source of genetic resources unexploited. The aim of this work was to perform the in silico molecular characterization of PR-5 genes and to extract DNA from Paraiba Semiarid plants genome, aiming PCR amplification. Hence, genomic DNAs were isolated from 16 plants collected from Caating Forest garden Olho D’água da Bica and the CES/UFCG, by using the CTAB and SDS protocols. The quantity and quality of extracted DNA varied according to species plant tissue, the protocols and methods used to analyze, electrophoresis and spectrophotometry. For some species, the DNA extraction by CTAB protocol reveled is more efficient, however carbohydrates and RNA contaminations and also degradations were observed. The use of SDS protocol is also efficient for obtaining of free contamination samples with proteins. Preliminary assays for DNA amplification by PCR were performed using two combinations of specific primers for PR-5 genes, but unsuccessful, probably more due to viability of utilized primers than quality and quantity of extracted DNAs. The absence of deposits in GenBank of PR-5 genes from studied plant species of the Caatinga revealed the need for this prospective study. Comparative in silico analysis of nucleotide and PR-5 proteins sequences are fundamental to the design of specific primers functional.