Proteomic analysis of aneuploid lines in the homeologous group 1 of the hexaploid wheat cultivar Courtot

Abstract

Three monosomic lines (MSLs) and three nullisomic lines (NSLs) of the homeologous group 1 and one euploid line of the bread wheat Triticum aestivum cultivar Courtot were used in a proteomic approach to investigate the effects of zero, one or two doses of chromosomes 1A, 1B and 1D on the amount of endosperm proteins. Polypeptides whose amounts changed significantly between each aneuploid line and the euploid line were identified using image analyses of two-dimensional gel electrophoresis patterns resulting from specific endosperm protein extractions. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry and electrospray ionization tandem mass spectrometry were also used for protein identification. Removing one chromosome or a chromosome pair allowed varying responses to be observed for the remaining endosperm protein genes. Compensation phenomena for the high molecular weight glutenin subunits (HMW-GS) were detected only in the MSLs. Subunits Bx7, By8 and Dy12 were the only HMW-GS overexpressed (from 152-737%) when chromosomes 1A or 1B or 1D were at hemizygous state. Thirteen new protein spots were detected only in the NSL1D, and seven were identified as HMW-GS analogs. These seven new spots may result from the expression of inactive genes. The HMW-GS were of significantly higher volume in MSLs, whereas the low molecular weight glutenin subunits and the gamma-gliadins were of lower volume in aneuploid lines. Most of the down-regulated proteins in the MSLs were storage proteins encoded at loci located on another chromosome pair. Complex regulations between chromosomes and loci of the homeologous groups 1 and 6 in bread wheat are discussed.

One Hundred Years of Grain Omics: Identifying the Glutens That Feed the World

“…Also related to wheat breeding, the impact of aneuploidy in wheat 85 and the effects of salicylic acid on growth and salt tolerance because exogenous salicylic acid pretreatment enhances the growth and tolerance to subsequent drought stress 86,87 , have been studied using proteomics.…”

Homoeologous recombination within bread wheat to develop novel combinations of HMW-GS genes: transfer of the Glu-A1 locus to chromosome 1D

“…By8) and Glu-D1 (Dx2 ? Dy12) loci (Dumur et al 2004). Grain protein content was not significantly different between Courtot and RR239 (data not shown).…”

“…The quantitative variations of Glu-B1 were consistent with the previous results observed in the aneuploid lines of Courtot. Subunits Bx7 and By8 had the greatest intrinsic ability to compensate for quantitative variations induced by changes in Glu-1 gene number on another homoeologous chromosome (Dumur et al 2004). …”

“…Gliadin identification was performed using acid PAGE following the method of Branlard et al (1990). Low-molecular weight glutenin subunits (LMW-GS) were extracted and identified according to the sequential extraction procedure described in Dumur et al (2004). Identification results obtained with the two previous methods were confirmed by mass spectrometer analyses.…”

“…The protocol of 2D gel electrophoresis (pH 3-10) was performed according to Dumur et al (2004) to reveal the majority of the storage proteins (glutenins and gliadins). Spots varying between the six replicates of the line RR239 and the six replicates of Courtot were identified by statistical analysis.…”