| The low-molecular-weight glutenin subunits of wheat make up one third of the seed storage proteins, LMW-GS and HMW-GS produce glutenin polymers with the intermolecular disulphide bonds, and they have great effects on wheat processing quality. Yunnan wheat(T.aestivum ssp.yunnanense King,AABBDD,2n=6x=42) is an endemic wheat germplasm in Yunnan Province and possesses many desirable characters such as good quality, high protein content, resistance to reharvest sprouting and yellow rust, tolerance to cold and infertile soil, etc. Moreover, Yunnan wheat has the potential value in the study of wheat origin and classification. LMW-GS genes have no intron inframe and are conserved in the N-terminal and C- terminal sequences. Therefore, a pair of degenerate primers was designed, and the full coding regions of LMW-GS genes were amplified from the T.aestivum ssp.yunnanense King accession YN11. Three different genes, LMWYN-1, LMWYN-2 and LMWYN-3, were identified from the 900 bp and 1100 bp amplification products. The coding regions of LMWYN-1 and LMWYN-2 were 1056 bp and 960 bp, and encoded two mature proteins with 330 and 299 amino acid residues, respectively. LMWYN-3 was a pseudogene due to that three stop codons were in its coding region. There were many differences in repetitive domain among three genes. The numbers of repeats were responsible for some variation in amino sequence of LMW-GS. According to the N-terminal sequences, they might belong to LMW-m. Through identity of the deduced amino acid sequences, three sequences were homologous of wheat LMW-GS. Prediction for secondary structure suggested that high content ofβ-turn existed in LMWYN-2, and it might have positive influences on the quality of flour. Phylogenetic analysis indicated that LMWYN-1 and LMWYN-3 could be both located in Glu-D3 locus, while LMWYN-2 could be located within Glu-B3 locus.
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