SDS-insoluble glutenin polymer formation in developing grains of hexaploid wheat: the role of the ratio of high to low molecular weight glutenin subunits and drying rate during ripening

The accumulation of polymeric proteins and the changes in molecular size distribution of these proteins were followed during grain filling and/or premature desiccation. The accumulation behavior of polymeric proteins and their constituent polypeptides (high and low molecular weight glutenin subunits, HMW-GS and LMW-GS) was determined by reversed phase-high performance liquid chromatography using a NaI/propanol purification procedure. With this new extraction and separation procedure, we have demonstrated that there was a coordinated initiation of storage protein biosynthesis, even if the accumulation rate varied greatly between the two main classes of proteins (i.e. monomeric and polymeric fractions). Moreover, the glutenin subunit composition was largely modified during glutenin accumulation. Both the HMW-GS/LMW-GS and HMW-GS-x/HMW-GS-y ratios increased significantly during the whole cell enlargement phase (from 16 to 37 d after anthesis). By applying premature grain desiccation during this physiological phase, we demonstrated that the polymerization index (SDS-insoluble polymers/total polymers) of the glutenin polymers was closely related to the HMW-GS/LMW-GS ratio of these proteins. An increase in the relative proportion of HMW-GS in glutenins caused the proportion of SDS-insoluble polymers to rise during grain desiccation. From these studies, it appears that the modification of the desiccation rate (grain desiccation at a constant temperature with variable relative humidity levels) induced a parallel modification of the glutenin insolubilization rate but did not affect the polymerization index of the glutenins at maturity.

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Accumulation and changes in molecular size distribution of polymeric proteins in developing grains of hexaploid wheats: role of the desiccation phase

Functional Plant Biology ◽

10.1071/pp99010 ◽

1999 ◽

Vol 26 (4) ◽

pp. 301 ◽

Cited By ~ 37

Author(s):

J. L. Carceller ◽

T. Aussenac

Keyword(s):

Molecular Weight ◽

Size Distribution ◽

High Molecular Weight ◽

Molecular Size ◽

Reversed Phase ◽

Size Exclusion ◽

Glutenin Subunits ◽

Soluble Polymers ◽

Molecular Size Distribution ◽

Insoluble Polymers

Two varieties of wheat differing in high molecular weight glutenin subunit composition (Soissons, 5+10, Glu-D1a allele; Thésée, 2+12, Glu-D1a allele) were examined to follow the accumulation of polymeric proteins and the changes in molecular size distribution of these proteins during grain filling. The accumulation behaviour of polymeric proteins was determined by size-exclusion-HPLC, multistacking SDS-PAGE and the constituent polypeptides (high molecular weight and low molecular weight glutenin subunits) by reversed-phase-HPLC. For both cultivars, the accumulation of each class of protein was highly asynchronous, especially between the early deposition of SDS-soluble polymers and the late deposition of SDS-insoluble polymers, such that the average molecular size of polymeric protein increased in the period from 30 to 45 days after anthesis in natural conditions. By applying premature grain desiccations during the cell enlargement phase, it was demonstrated that the SDS-insoluble polymers formation was closely related with the process of water loss from the grain. Moreover, the rapid accumulation of SDS-insoluble polymers coincided with a rapid decrease in mass of both SDS-soluble polymers and monomers, suggesting an aggregative mechanism. Over the same period, the molecular size distribution of the polymers which can be used to differentiate the two genotypes studied, is highly correlated with the percentage of high molecular weight glutenin subunits in glutenins present in kernels when desiccation occurred. The formation of SDS-insoluble fraction is discussed in connection with the specific contribution of high molecular weight glutenin subunits to the formation of polymers (subunits linked by disulfide bonds).

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Genetic diversity of high and low molecular weight glutenin subunits in Saharan bread and durum wheats from Algerian oases

Czech Journal of Genetics and Plant Breeding ◽

10.17221/105/2011-cjgpb ◽

2012 ◽

Vol 48 (No. 1) ◽

pp. 23-32 ◽

Cited By ~ 11

Author(s):

I. Bellil ◽

M. Chekara Bouziani ◽

D. Khelifi

Keyword(s):

Genetic Diversity ◽

Molecular Weight ◽

Durum Wheat ◽

Bread Wheat ◽

Allelic Variation ◽

Low Molecular Weight ◽

Glutenin Subunits ◽

Lmw Glutenin Subunits ◽

Genotypic Identification ◽

Diversity Studies

Saharan wheats have been studied particularly from a botanical viewpoint. Genotypic identification, classification and genetic diversity studies to date were essentially based on the morphology of the spike and grain. For this, the allelic variation at the glutenin loci was studied in a set of Saharan bread and durum wheats from Algerian oases where this crop has been traditionally cultivated. The high molecular weight and low molecular weight glutenin subunit composition of 40 Saharan bread and 30 durum wheats was determined by SDS-PAGE. In Saharan bread wheats 32 alleles at the six glutenin loci were detected, which in combination resulted in 36 different patterns including 17 for HMW and 23 for LMW glutenin subunits. For the Saharan durum wheats, 29 different alleles were identified for the five glutenin loci studied. Altogether, 29 glutenin patterns were detected, including 13 for HMW-GS and 20 for LMW-GS. Three new alleles were found in Saharan wheats, two in durum wheat at the Glu-B1 and Glu-B3 loci, and one in bread wheat at the Glu-B1 locus. The mean indices of genetic variation at the six loci in bread wheat and at the five loci in durum wheat were 0.59 and 0.63, respectively, showing that Saharan wheats were more diverse. This information could be useful to select Saharan varieties with improved quality and also as a source of genes to develop new lines when breeding for quality.

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Identification of low-molecular weight glutenin subunits of wheat associated with bread-making quality

Plant Breeding ◽

10.1111/j.1439-0523.2004.00978.x ◽

2004 ◽

Vol 123 (4) ◽

pp. 355-360 ◽

Cited By ~ 23

Author(s):

W. Maruyama-Funatsuki ◽

K. Takata ◽

Z. Nishio ◽

T. Tabiki ◽

E. Yahata ◽

...

Keyword(s):

Molecular Weight ◽

Low Molecular Weight ◽

Glutenin Subunits ◽

Bread Making

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Simultaneous Determination of Human Serum Albumin and Low-Molecular-Weight Thiols after Derivatization with Monobromobimane

Molecules ◽

10.3390/molecules26113321 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3321

Author(s):

Katarzyna Kurpet ◽

Rafał Głowacki ◽

Grażyna Chwatko

Keyword(s):

Molecular Weight ◽

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Simultaneous Determination ◽

Reversed Phase ◽

Fluorescence Labeling ◽

Detector Response ◽

Low Molecular Weight

Biothiols are extremely powerful antioxidants that protect cells against the effects of oxidative stress. They are also considered relevant disease biomarkers, specifically risk factors for cardiovascular disease. In this paper, a new procedure for the simultaneous determination of human serum albumin and low-molecular-weight thiols in plasma is described. The method is based on the pre-column derivatization of analytes with a thiol-specific fluorescence labeling reagent, monobromobimane, followed by separation and quantification through reversed-phase high-performance liquid chromatography with fluorescence detection (excitation, 378 nm; emission, 492 nm). Prior to the derivatization step, the oxidized thiols are converted to their reduced forms by reductive cleavage with sodium borohydride. Linearity in the detector response for total thiols was observed in the following ranges: 1.76–30.0 mg mL−1 for human serum albumin, 0.29–5.0 nmol mL−1 for α-lipoic acid, 1.16–35 nmol mL−1 for glutathione, 9.83–450.0 nmol mL−1 for cysteine, 0.55–40.0 nmol mL−1 for homocysteine, 0.34–50.0 nmol mL−1 for N-acetyl-L-cysteine, and 1.45–45.0 nmol mL−1 for cysteinylglycine. Recovery values of 85.16–119.48% were recorded for all the analytes. The developed method is sensitive, repeatable, and linear within the expected ranges of total thiols. The devised procedure can be applied to plasma samples to monitor biochemical processes in various pathophysiological states.

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Proteomic Determination of Low-Molecular-Weight Glutenin Subunit Composition in Aroona Near-Isogenic Lines and Standard Wheat Cultivars

International Journal of Molecular Sciences ◽

10.3390/ijms22147709 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7709

Author(s):

Kyoungwon Cho ◽

You-Ran Jang ◽

Sun-Hyung Lim ◽

Susan B. Altenbach ◽

Yong Q. Gu ◽

...

Keyword(s):

Molecular Weight ◽

Allelic Variation ◽

Reversed Phase ◽

Glutenin Subunit ◽

Low Molecular Weight ◽

Near Isogenic Lines ◽

Wheat Cultivars ◽

Reliable Determination ◽

Isogenic Lines

The low-molecular weight glutenin subunit (LMW-GS) composition of wheat (Triticum aestivum) flour has important effects on end-use quality. However, assessing the contributions of each LMW-GS to flour quality remains challenging because of the complex LMW-GS composition and allelic variation among wheat cultivars. Therefore, accurate and reliable determination of LMW-GS alleles in germplasm remains an important challenge for wheat breeding. In this study, we used an optimized reversed-phase HPLC method and proteomics approach comprising 2-D gels coupled with liquid chromatography–tandem mass spectrometry (MS/MS) to discriminate individual LMW-GSs corresponding to alleles encoded by the Glu-A3, Glu-B3, and Glu-D3 loci in the ‘Aroona’ cultivar and 12 ‘Aroona’ near-isogenic lines (ARILs), which contain unique LMW-GS alleles in the same genetic background. The LMW-GS separation patterns for ‘Aroona’ and ARILs on chromatograms and 2-D gels were consistent with those from a set of 10 standard wheat cultivars for Glu-3. Furthermore, 12 previously uncharacterized spots in ‘Aroona’ and ARILs were excised from 2-D gels, digested with chymotrypsin, and subjected to MS/MS. We identified their gene haplotypes and created a 2-D gel map of LMW-GS alleles in the germplasm for breeding and screening for desirable LMW-GS alleles for wheat quality improvement.

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Composition of and variation in high- and low-molecular weight glutenin subunits, and omega gliadins in Ethiopian tetraploid wheat germplasm

Plant Genetic Resources ◽

10.1079/pgr2006110 ◽

2006 ◽

Vol 4 (2) ◽

pp. 134-143 ◽

Cited By ~ 7

Author(s):

Faris Hailu ◽

Eva Johansson ◽

Arnulf Merker ◽

Getachew Belay ◽

Harjit-Singh ◽

...

Keyword(s):

Molecular Weight ◽

Tetraploid Wheat ◽

Glutenin Subunit ◽

Low Molecular Weight ◽

Glutenin Subunits ◽

Hmw Glutenin Subunits ◽

Lmw Glutenin Subunits ◽

Hmw Glutenin ◽

Omega Gliadins ◽

High Degree

A collection of 120 Ethiopian tetraploid wheat accessions was analysed for high-molecular weight (HMW) glutenin subunit, low-molecular weight (LMW) glutenin subunit and omega gliadin composition by SDS–PAGE. For the HMW glutenin subunits, a new allelic variant, 2****, was detected which has not been previously described at the Glu-A1 locus. A high proportion of Glu-A1x banding pattern was observed in durum wheat. For the Glu-B1 locus four different banding patterns were detected. Among those HMW glutenin subunits, 7+8 were the most common, while subunits 14+15 and 6+8 were found to be rare. A high degree of variation was evident for the LMW glutenin subunits and D-zone omega gliadins. The association of the composition of the gluten with quality has been discussed. This wide variation can be used in improving the quality of wheat and to widen its genetic base.

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