Gene Characterization of a Serine Proteases in Tribolium castanueum: Implications for Alternative Control Strategies

When stored grains are infested by post-harvest insects, they become unfit for human consumption and cause significant financial losses. We present in our work structural and functional characterization of proteases secreted from Tribolium castanueum (TricaPRO) that was investigated biochemically and by PCR and sequence analysis. Understanding the kinds of enzymes found in Tribolium castanueum is essential for effective management of insect control with appropriate proteinase inhibitor. Serine and cysteine proteinases are the two main kinds of proteinases found in this insect digestive system. An open reading frame of 792 bp translated to 263 amino acid residues was revealed by analyzing the results of the protease gene amplification from the entire adult genome using specific primers based on the NCBI projected sequence. The bioinformatics analyses showed that the deduced amino acid sequence likely corresponds to protease closely related to insect. The sequence analysis by BLAST in the NCBI databases showed high similarity scores revealing that the TricaPRO sequence shares identity rates of 72.69 % with brachyurin-like of Tribolium madens (XP_044267572.1) and 58 % with brachyurin-like of Zophobas morio XP_063913854.1 suggesting that these species may belong to the same category. The conserved domain, the secondary and three-dimensional structures of Tribolium castanueum were also predicted with iterative threading assembly refinement (I-Tasser) software. Phylogenetic analysis was carried out using Molecular Evolutionary Genetic Analysis software. The TricaPRO add to the Bank of insect protease suggest an important biocontrol applications.