Cloning, Expression and Characterization of PnLOX2 Gene Related to Aspergillus flavus-resistance from Peanut (Arachis hypogaea L.) Seed Coat

Aspergillus flavus is one of the major diseases of peanut. The objective of the study was to clone PnLOX2 gene from peanut seed coat and analyze its expression. Real-time RT-PCR analysis indicated that the gene was overexpressed in the challenge of Aspergillus flavus and the greatest expression occurred 10 days after inoculation. The full length of PnLOX2 gene was 2592bp and encoded a 97.5kDa protein containing 863 amino acids. The fusion protein (apparent 121.5kDa) only existed in the precipitation and the maximum was obtained by inducing at 37ºC for 3.5h. As a result of response to the challenge of Aspergillus flavus, PnLOX2 gene was more greatly expressed in the resistant genotype than in the susceptible genotype. It indicated that PnLOX2 gene was closely related to Aspergillus flavus-resistance of peanut. Further investigations were needed to bacteriostatically identify the gene in vitro.