Sequence Analysis Of α-amylase Inhibitors Genes From Triticum Dicoccoides

Triticum dicoccoides (2n=4x=28) with genome constitution AABB is the progenitor of cultivated wheat (Triticum aestivum, 2n=6x=42, AABBDD) that presumably originated in and adaptively diversified from Israel. In cereal seeds, a-amylase inhibitors proteins with 120-130 amino acids, which include trypsin inhibitors as well as a-amylase inhibitors, were known as one great family on the basis of the homology of their amino acid sequence. For weevil control, a-amylase inhibitors could be used through plant genetic engineering. However, many insects have several a-amylases that differ in specificity, and successful utilization of a food source is dependent on the presence of a a-amylase for which there is no specific inhibitor. In this study, the coding sequences of 24 kDa a-amylase inhibitors with resistance to insects in three T. dicoccoides accessions were investigated, and seventy-two genes were obtained. According to sequences alignment, it was found that the 24kDa a-amylase inhibitors in T. dicoccoides were encoded by multi-gene. The distribution of inhibitor forms had no distinct difference in different accessions of T. dicoccoides by x~2 test. Due to that the a-amylase inhibitors in 24kDa family were much conserved in evolution of Triticum, the nucleotide sequences of 24kDa a-amylase inhibitors shared very high coherence.The nucleotide sequences of a-amylase inhibitors were with high coherence between the genes from T. dicoccoides and related species, which indicated that the a-amylase inhibitors in this family were conserved in evolution. Forty-four synonymous changes were found in the 55 SNPs, which induce 38 variations of...