Generation of novel high quality HMW-GS genes in two introgression lines of Triticum aestivum/Agropyron elongatum

<p>Abstract</p> <p>Background</p> <p>High molecular weight glutenin subunits (HMW-GS) have been proved to be mostly correlated with the processing quality of common wheat (<it>Triticum aestivum</it>). But wheat cultivars have limited number of high quality HMW-GS. However, novel HMW-GS were found to be present in many wheat asymmetric somatic hybrid introgression lines of common wheat/<it>Agropyron elongatum</it>.</p> <p>Results</p> <p>To exploit how these new subunits were generated, we isolated HMW-GS genes from two sib hybrid lines (II-12 and 11-4-6) and compared them with those from their parents. The result shows that two genes of hybrid (<it>H11-3-3 </it>and <it>H11-4-3</it>) are directly introgressed from the donor parent <it>Agropyron elongatum</it>; one hybrid gene (<it>H1Dx5</it>) comes from point mutation of a parental wheat gene (<it>1Dx2.1</it>); two other hybrid genes (<it>H1By8 </it>and <it>H1By16</it>) are likely resulting from unequal crossover or slippage of a parental wheat gene (<it>1By9.1</it>); and the sixth novel hybrid gene (<it>H1Dy12</it>) may come from recombination between two parental genes.</p> <p>Conclusion</p> <p>Therefore, we demonstrate that novel HMW-GS genes can be rapidly created through asymmetric somatic hybridization in a manner similar with the evolution mechanism of these genes supposed before. We also described gene shuffling as a new mechanism of novel HMW-GS gene formation in hybrids. The results suggest that asymmetric somatic hybridization is an important approach for widening HMW-GS genebank of wheat quality improvement.</p

Comparison of peptide sequences deduced from three 1980 bp DNA sequences: , and

<p><b>Copyright information:</b></p><p>Taken from "Generation of novel high quality HMW-GS genes in two introgression lines of /"</p><p>http://www.biomedcentral.com/1471-2148/7/76</p><p>BMC Evolutionary Biology 2007;7():76-76.</p><p>Published online 15 May 2007</p><p>PMCID:PMC1884143.</p><p></p> Seven of 10 discrepant bases before position 1210 are the same between and , while 9 of another 12 discrepant bases after position 1210 are the same between and

Comparison of part DNA sequences from repetitive domain of three alleles and a y-type allele of

<p><b>Copyright information:</b></p><p>Taken from "Generation of novel high quality HMW-GS genes in two introgression lines of /"</p><p>http://www.biomedcentral.com/1471-2148/7/76</p><p>BMC Evolutionary Biology 2007;7():76-76.</p><p>Published online 15 May 2007</p><p>PMCID:PMC1884143.</p><p></p> and is the coding sequence of novel subunit of hybrid; is the coding sequence of 1By9.1 subunit of common wheat Jinan177

Comparison of mature peptide sequences deduced from DNA sequences of and

<p><b>Copyright information:</b></p><p>Taken from "Generation of novel high quality HMW-GS genes in two introgression lines of /"</p><p>http://www.biomedcentral.com/1471-2148/7/76</p><p>BMC Evolutionary Biology 2007;7():76-76.</p><p>Published online 15 May 2007</p><p>PMCID:PMC1884143.</p><p></p

Sketch map of possible pathway through which novel hybrid HMW-GS genes come from, a): come from via single base mutation, the arrow means the SNPs

<p><b>Copyright information:</b></p><p>Taken from "Generation of novel high quality HMW-GS genes in two introgression lines of /"</p><p>http://www.biomedcentral.com/1471-2148/7/76</p><p>BMC Evolutionary Biology 2007;7():76-76.</p><p>Published online 15 May 2007</p><p>PMCID:PMC1884143.</p><p></p> b): and of hybrid generate from duplication of a block of repeats of . c): of hybrid engender from recombination between of and of parent wheat Jinan177