Sequencing and expression analysis of a novel HMW-glutenin gene Kx from Crithopsis delileana / 生物工程学报

ABSTRACT

Using SDS-PAGE analysis, the High-molecular-weight (HMW) glutenin subunits of two Crithopsis delileana accessions were detected. It was found that the two accessions had the same HMW glutenin subunits. Only one HMW glutenin subunit with the similar electrophoresis mobility to the y-type HMW glutenin subunit of hexaploid wheat was observed in C. delileana. However, It was indicated that this glutenin subunit was an x-type glutenin subunit Kx by gene sequence analysis. The full coding region of Kx gene is 2052bp and could encodes a mature protein with 661 amino acid residues. The Kx gene could be expressed in the bacterial expression system, and the expressed protein had the same electrophoresis mobility as that in the seed of C. delileana. The primary structure of Kx subunit was very similar to the x-type HMW glutenin subunits encoded by the A, B and D genomes of wheat, the C and U genomes of Aegilops, and the R genome of Secale cereale. In the phylogenetic analysis, Kx subunit was clustered together with Ax1 subunit by an interior parallelled branch. In conclsion, Kx gene is a novel x type glutenin subunit gene from C. delileana.