Specificity characteristics of monoclonal antibodies to wheat grain storage proteins

The isopropanol-soluble seed storage proteins, prolamins, were studied in 18 different genera of the tribe Triticeae by gel electrophoresis, Coomassie staining, and immunoblot assays. The monoclonal antibodies were originally raised against cultivated barley (Hordeum vulgare L.) hordein, and their reactions had been tested earlier on wild Hordeum species. The study showed that all the investigated Triticeae species produce prolamins and that structural similarities can be found throughout the tribe. The presence of the same antigenic sites in all the species indicates that the polypeptides contain well-conserved regions. They also indicate that the prolamins of the Triticeae species have a common evolutionary origin. In all the investigated species an antigenic site that is common to the B- and C-hordeins of barley was detected. Some of the reacting polypeptides also contained a site that is only present in the B-hordeins. The B-hordein specific site was found in all genera except Agropyron, Hordelymus, and Secale. This shows that although there are similarities between individual polypeptides, the composition of the various prolamin groups may vary between different genera. In the polyploid Elymus species different banding patterns were observed depending on what basic genomes were represented. The results suggest a direct correlation between the presence of a fast migrating polypeptide containing the B-hordein specific site and the presence of the H genome.Key words: Triticeae, prolamin, monoclonal antibodies, evolution, multigene family.

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The endosperm-specific transcription factor TaNAC019 regulates glutenin and starch accumulation and its elite allele improves wheat grain quality

The Plant Cell ◽

10.1093/plcell/koaa040 ◽

2021 ◽

Author(s):

Yujiao Gao ◽

Kexin An ◽

Weiwei Guo ◽

Yongming Chen ◽

Ruijie Zhang ◽

...

Keyword(s):

Transcription Factor ◽

Grain Quality ◽

Storage Proteins ◽

Seed Storage Proteins ◽

Starch Accumulation ◽

Processing Quality ◽

Starch Metabolism ◽

Wheat Grain ◽

Knock Out ◽

Elite Allele

Abstract In wheat (Triticum aestivum L.), breeding efforts have focused intensively on improving grain yield and quality. For quality, the content and composition of seed storage proteins (SSPs) determine the elasticity of wheat dough and flour processing quality. Moreover, starch levels in seeds are associated with yield. However, little is known about the mechanisms that coordinate SSP and starch accumulation in wheat. In this study, we explored the role of the endosperm-specific NAC transcription factor TaNAC019 in coordinating SSP and starch accumulation. TaNAC019 binds to the promoters of TaGlu-1 loci, encoding high molecular weight glutenin (HMW-GS), and of starch metabolism genes. Triple knock-out mutants of all three TaNAC019 homoeologs exhibited reduced transcript levels for all SSP types and genes involved in starch metabolism, leading to lower gluten and starch contents, and in flour processing quality parameters. TaNAC019 directly activated the expression of HMW-GS genes by binding to a specific motif in their promoters and interacting with the TaGlu-1 regulator TaGAMyb. TaNAC019 also indirectly regulated the expression of TaSPA, an ortholog of maize Opaque2 that activates SSP accumulation. Therefore, TaNAC019 regulation of starch- and SSP-related genes has key roles in wheat grain quality. Finally, we identified an elite allele (TaNAC019-BI) associated with flour processing quality, providing a candidate gene for breeding wheat with improved quality.

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The study of the quality of flour obtained from wheat at the stages of long-term storage

10.33920/igt-01-2106-07 ◽

2021 ◽

pp. 449-456

Author(s):

K.B. Guryeva ◽

S.L. Beletskiy ◽

N.A. Khaba

Keyword(s):

Wheat Flour ◽

Physicochemical Parameters ◽

Grain Storage ◽

Wheat Grain ◽

Long Term Storage ◽

Term Storage

This article presents an analysis of the results of the study of flour obtained from batches of wheat grain at the stages of storage. It is shown that during the observed period of grain storage, the quality of the obtained wheat flour was stable and corresponded to the highest grade in terms of physicochemical parameters. Wheat of the 3rd class after 6 years of storage can be used for milling purposes for the production of bakery flour.

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Cell-Free Synthesis of Wheat Prolamins

Functional Plant Biology ◽

10.1071/pp9820059 ◽

1982 ◽

Vol 9 (1) ◽

pp. 59 ◽

Cited By ~ 6

Author(s):

GR Donovan ◽

JW Lee ◽

TJ Longhurst

Keyword(s):

Storage Proteins ◽

Signal Sequence ◽

Polyacrylamide Gel Electrophoresis ◽

Wheat Grain ◽

Synthesis System ◽

Molecular Weight Range ◽

Post Translational Modifications ◽

Membrane Bound ◽

Protein Synthesis System ◽

Cell Free Protein Synthesis

Total RNA, polyribosomes and polyribosomal RNA have been isolated from immature wheat grain and used to prime the wheat-germ cell-free protein synthesis system to produce storage protein. The synthesis of wheat prolamins, a major fraction of storage proteins, was mainly associated with membrane-bound polyribosomes. The ratio of bound to free polyribosomes increased from one at 8 days to approximately three at 32 days post-anthesis. SDS polyacrylamide gel electrophoresis and fluorography of the prolamins showed that the same components were being synthesized and accumulated from 12 days post-anthesis onward. Evidence is presented that prolamins within the molecular weight range 35 000-45 000 may be translated with a signal sequence attached. These signal sequences are rapidly removed during translation and further post-translational modifications may occur over longer periods.

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