Identification, Cloning and Characterisation of a HMW-Glutenin Gene from an Old Hungarian Wheat Variety, Bánkúti 1201

Abstract

Despite its good functional properties, the variety Bánkúti 1201 has been found to possess 2+12 or 3+12 allele composition on chromosome 1D. In order to determine the reason for its quality traits a gene-specific PCR technique was applied in preliminary experiments to examine the HMW glutenin allele composition of the variety. In the course of the analysis a fragment characteristic of Bánkúti 1201 was identified and the nucleotide sequence was determined. This showed the presence of a 1Ax2* gene variant which, despite near homology, differed from the original 1Ax2* gene at one important point. At 1181 bp of the 1Ax2* sequence nucleotide exchange was observed which is the middle nucleotide of the TCT-TGT base triplet, involving the exchange of serine for cysteine. The gene was designated 1Ax2*B. The presence of an extra sulphydryl group, like that of the extra cysteine in the 1Dx5 gene, facilitates the formation of further disulphide bonds, might lead to an improvement in gluten quality characters.Key wordswheatHMW-glutenincysteine residuestorage proteins