Evidence of intralocus recombination at the Glu-3 loci in bread wheat (Triticum aestivum L.)

Authors: IBBA, MARIA ITRIA - Washington State University; Kiszonas, Alecia; Morris, Craig

Submitted to: Annual International Plant & Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2016
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The low-molecular weight glutenin subunits (LMW-GSs) are a class of wheat seed storage proteins that play a critical role in the determination of wheat flour bread-making quality. These proteins are encoded by multigene families located at the orthologous Glu-3 loci (Glu-A3, Glu-B3 and Glu-D3), on the short arm of the homoeologous group 1 chromosomes. Due to the complexity of these chromosomal regions and the high sequence similarity between different LMW-GS genes, their genetic organization and recombination characteristics are still incompletely understood. In this study, the presence of intralocus recombination at the Glu-3 loci was investigated in two bread wheat recombinant inbred line (RIL) populations and one doubled haploid (DH) population, all segregating for the Glu-A3, Glu-B3 and Glu-D3 loci. The analysis was conducted using a LMW-GS gene marker system that consists of the amplification of the complete set of the LMW-GS genes and their successive visualization by capillary electrophoresis. Recombinant marker haplotypes were detected in the two RIL and the DH populations with different recombination rates depending on the locus and the population. Tight linkage was observed between amplicons representing i-type and s-type LMW-GS genes located, respectively, at the Glu-A3 and Glu-B3 loci. Results of this study will help to elucidate the genetic linkage present between different LMW-GS genes, the structure of this portion of the genome, and to develop more specific molecular markers that better represent the genetic diversity of these loci.