Molecular Cloning, Classification And Development Of Molecular Markers Of Wheat LMW-GS Genes

The wheat low-molecular-weight glutenin subumts (LMW-GS) are among the major components of the wheat seed storage proteins and are close associated with wheat quality.In the present study, we attempt to isolate novel LMW-GS gene clones from wheat. On the basis of the sequence information, the known LMW-GS genes are divided into groups and their chromosome locations are also determined. The genome specific markers, which are also specific to each of LMW-GS gene groups, have been subsequently developed. One of these markers is subjected to detect length variations of LMW-i genes in A-genome diploid wheats.The main results are presented as following:1. Molecular Cloning of LMW-GS Genes from WheatBased on the conserved sequences of the known LMW-GS gene, a primer set was constructed for PCR cloning of LMW-GS genes from wheat cultivar 'Chuannong 16', 'Chuanmai42' and one accession of T.aestevum ssp.tibet shao. Six novel LMW-GS genes, AY296752 (LMWCN16-1), AY296753 (LMWCN16-2), DQ415644 (LMWCM42-1), AY299458 (LMW908-1), AY299457 (LMW908-2) and AY299459 (LMW908-3) were isolated, among which LMWCN16-1 and LMW908-3 are putative pseudogenes due to the presence of in frame stop condons. The differences between LMWCN16-2, LMW908-1 and known LMW-GS are the substitutions of amino acids. However, LMWCN16-2 and LMW908-2 have significant difference on sequence and structure, and thus possess the potential effects on the formation of the glutenin polymers.