| The types and numbers of the low molecular weight glutenin subunits(LMW-GS)have a imporent influence on the end-use quality of wheat flours.Isolated LMWglutenin sequence from T.aestivum,T.durum,T.boeoticum,T,momococum and Ae.tauschii all revealed that the coding sequence of these genes were moderate in length and conserved in the composition of nucleotide and no intron in frame.All these character led to the possibility of isolation these genes by PCR strategies.A T.durum-Ae,tauschii synthesized 6x-wheat named SHW-Z1 was studied.We isolated and sequenced six coding sequence of LMW glutenin from SHW-Z1.The main results were as follows:1.Amplified LMW glutenin coding sequence from SHW-Z1 by primer of Glu-D3 locus encoded glutenin were about 950bp and 1010bp in length.These length were nearly equal to the coding sequence of LMW glutenin from other sources.2.Six LMW glutenin sequences(named to x-1,x-2,x-3,d-15,d-17 and d-21)were obtained after positive clone screen and sequencing.The coding sequences of them were 897 bp,897 bp,915bp,1011bp,1053bp and 960bp respectively.Among them,x-3,d-15 and d-17 had open reading frame and could encoding three mature proteins including 304,336 and 350 amino acid residues,respectively,x-1,x-2 and d-21 could not encode any mature proteins because of one each inframe stop coden in their coding sequences.3.Multiple sequences alignment suggested that six isolated sequences were homologous of wheat LMW glutenin.It could be predicated that x-1,x-2,x-3 and d-15 were probably encoded by Glu-D3 locus when d-15 was probably encoded by Glu-B3,but the encoding locus of d-17 was not clear.4.Sequences between x-3 and DQ457417,between d-15 and AB062852 and between d-17 and Y14104 were very similar in primary structures and amino acids compositions suggested that three pairs might have the very similar quality functions to wheat flours.However,there were only 7 cysteine residue in x-3,which would influence the quality of wheat flours.
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