Molecular cloning and characterization of an up-regulated UDP-glucosyltransferase gene induced by DON from Triticum aestivum L. cv. Wangshuibai.

ABSTRACT

Fusarium head blight, also called scab, is a serious disease of small grain cereals and maize. Scab can not only cause yield loss, more seriously is that it can also deteriorate seed quality by contaminating the infected grains with trichothecenes toxins harmful to human and animal health. Deoxynivalenol (DON) is one of the most important toxin members. It was proposed that DON acted first as a virulence factor during fungal pathogenesis and then accumulated in grain to levels posing a threat to human and animal health. In the present research, by expression analysis of DON-induced samples using GeneChip Wheat Genome Array ( http//www.affymetrix.com/products/arrays/specific/wheat.affx ), a DON-resistance related gene TaUGT3 (GenBank accession FJ236328) was cloned and characterized from a scab resistant wheat (Triticum aestivum L.) variety Wangshuibai. The full-length cDNA of TaUGT3 was 1,755 bp and contained a putative open reading frame (ORF) with 496 amino acids encoding a UDP-glucosyltransferase (UGT). TaUGT3 showed high similarity in amino acid level with DOGT1 gene in Arabidopsis, which is able to detoxify DON. TaUGT3 was located on the group 3 chromosomes of wheat using nulli-tetrasomic lines and deletion lines of Chinese Spring. Co-transformed of TaUGT3 with GFP genes to onion epidermis cells using transient transformation technique by microprojectile bombardment indicated the subcellular location of the protein encoded by TaUGT3 was in the plasma membrane and nuclear. Transformation and overexpression of the TaUGT3 gene in Arabidopsis could enhance tolerance against DON.