Glutenin Subunit Genes Research Articles

Detection of high-molecular-weight glutenin subunit genes for 1Dx2 and 1Dx5 using loop-mediated isothermal amplification assay

High-molecular-weight glutenin subunits (HMW-GS) in wheat grain are the major determinants of dough elasticity and viscosity and thus of bread-making quality. PCR-based molecular markers designed based on DNA polymorphisms were used to analyze HMW-GS genes in wheat. The loop-mediated isothermal amplification (LAMP) assay is a simple and rapid method for specific detection of genomic DNA target sequences. In the present study, we designed a set of LAMP markers by targeting the unique sequences of 1Dx2 and 1Dx5 genes. The primers could effectively distinguish the 1Dx2 and 1Dx5 genes from other genes at the Glu-1 locus. The results were confirmed by agarose gel electrophoresis. For visualization, ethidium bromide was used, and fluorescence only appeared in the positive samples. Under optimal conditions, the detection could be finished in 1 h. Thirty-eight wheat cultivars with known HMW-GS were used to validate LAMP markers for 1Dx2 and 1Dx5 genes. Only DNA samples with target genes could be amplified, and the results could be read easily using this method. The tests using LAMP were easy to perform, rapid, and sensitive. Thus, the current study results have the potential to be a powerful tool for the detection of HMW-GS genes in wheat.

Functional Characterization of TaFUSCA3, a B3-Superfamily Transcription Factor Gene in the Wheat.

The end-use quality of wheat, including its unique rheology and viscoelastic properties, is predominantly determined by the composition and concentration of gluten proteins. While, the mechanism regulating expression of the seed storage protein (SSP) genes and other related genes in wheat remains unclear. In this study, we report on the cloning and functional identification of TaFUSCA3, a B3-superfamily transcription factor (TF) gene in wheat. Sequence alignment indicated that wheat and barley FUSCA3 genes are highly conserved. Quantitative reverse-transcription (qRT)-PCR analysis showed that the transcript of TaFUSCA3 was accumulated mostly in the stamens and the endosperms of immature wheat seeds. Yeast-one-hybrid results proved that the full-length TaFUSCA3 and its C-terminal region had transcriptional activities. Yeast-two-hybrid and bimolecular fluorescence complementation assays indicated that TaFUSCA3 could activate the expression of the high molecular weight glutenin subunit gene Glu-1Bx7 and interact with the seed-specific bZIP protein TaSPA. DNA-protein-interaction enzyme-linked immunosorbent assay demonstrated that TaFUSCA3 specifically recognizes the RY-box of the Glu-1Bx7 promoter region. Transient expression results showed that TaFUSCA3 could trans-activate the Glu-1Bx7 promoter, which contains eight RY-box sequences. TaFUSCA3 was unable to activate the downstream transcription when the RY-box was fully mutated. TaFUSCA3 could activate the transcription of the At2S3 gene promoter in a complementation of loss-of-function experiment using the Arabidopsis thaliana line fus3-3, which is a FUSCA3 mutant, demonstrating the evolutionary conservation of the TaFUSCA3 gene. In conclusion, the wheat B3-type TF, TaFUSCA3, is functional conserved between monocot and dicot, and could regulate SSP gene expression by interacting specifically with TaSPA.

Definition of the low molecular weight glutenin subunit gene family members in a set of standard bread wheat (Triticum aestivum L.) varieties

Low-molecular-weight glutenin subunits (LMW-GS) are a class of seed storage proteins that play a major role in the determination of the viscoelastic properties of wheat dough. The LMW-GSs are encoded by multi-gene families at the Glu-A3, Glu-B3 and Glu-D3 loci, with more than 15 genes present in most bread wheat varieties. However, the genic profile associated with different alleles has not been clearly defined. Here, the LMW-GSs in a set of standard varieties were analyzed using molecular markers. In most cases, each Glu-3 allele was represented by a specific haplotype; however, some alleles were undistinguishable. The Glu-A3e and Glu-A3g alleles showed an identical marker haplotype, as did the alleles Glu-B3c and Glu-B3d, and Glu-B3f and Glu-B3ab. In contrast, two haplotypes among varieties designated Glu-D3c were differentiated. The marker profiles present at the Glu-D3 locus exhibited less variation compared to the genes at the Glu-A3 and Glu-B3 loci. Results show the potential of the LMW-GS gene marker system in the characterization of the LMW-GS alleles present in specific bread wheat varieties, and its reconciliation with protein-based nomenclature. This approach will advance the understanding of the contribution of each of the LMW-GS gene alleles in the control of the end-use quality.

Identification and molecular characterization of one novel 1SPl-encoded s-type low molecular weight glutenin B-subunit from 1Sl(1B) substitution line of wheat variety Chinese Spring (Triticum aestivum)

Abstract(2

A Catalog of Regulatory Sequences for Trait Gene for the Genome Editing of Wheat.

Wheat has been cultivated for 10000 years and ever since the origin of hexaploid wheat it has been exempt from natural selection. Instead, it was under the constant selective pressure of human agriculture from harvest to sowing during every year, producing a vast array of varieties. Wheat has been adopted globally, accumulating variation for genes involved in yield traits, environmental adaptation and resistance. However, one small but important part of the wheat genome has hardly changed: the regulatory regions of both the x- and y-type high molecular weight glutenin subunit (HMW-GS) genes, which are alone responsible for approximately 12% of the grain protein content. The phylogeny of the HMW-GS regulatory regions of the Triticeae demonstrates that a genetic bottleneck may have led to its decreased diversity during domestication and the subsequent cultivation. It has also highlighted the fact that the wild relatives of wheat may offer an unexploited genetic resource for the regulatory region of these genes. Significant research efforts have been made in the public sector and by international agencies, using wild crosses to exploit the available genetic variation, and as a result synthetic hexaploids are now being utilized by a number of breeding companies. However, a newly emerging tool of genome editing provides significantly improved efficiency in exploiting the natural variation in HMW-GS genes and incorporating this into elite cultivars and breeding lines. Recent advancement in the understanding of the regulation of these genes underlines the needs for an overview of the regulatory elements for genome editing purposes.

Flour Quality and Related Molecular Characterization of High Molecular Weight Glutenin Subunit Genes from Wild Emmer Wheat Accession TD-256.

To clarify the effect of high molecular weight glutenin subunit (HMW-GS) from wild emmer wheat on flour quality, which has the same mobility as that from common wheat, the composition and molecular characterization of HMW-GS from wild emmer wheat accession TD-256, as well as its flour quality, were intensively analyzed. It is found that the mobilities of Glu-A1 and Glu-B1 subunits from TD-256 are consistent with those of bread wheat cv. 'XiaoYan 6'. Nevertheless, dough rheological properties of TD-256 reveal its poor flour quality. In the aspect of molecular structure from HMW-GS, only two conserved cysteine residues can be observed in the deduced protein sequence of 1Bx14* from TD-256, while most Glu-1Bx contain four conserved cysteine residues. In addition, as can be predicted from secondary structure, the quantity both of α-helixes and their amino acid residues of the subunits from TD-256 is fewer than those of common wheat. Though low molecular weight glutenin subunit (LMW-GS) and gliadin can also greatly influence flour quality, the protein structure of the HMW-GS revealed in this work can partly explain the poor flour quality of wild emmer accession TD-256.

Low molecular weight glutenin subunit gene Glu-B3h confers superior dough strength and breadmaking quality in wheat (Triticum aestivum L.).

Low molecular weight glutenin subunit is one of the important quality elements in wheat (Triticum aestivum L.). Although considerable allelic variation has been identified, the functional properties of individual alleles at Glu-3 loci are less studied. In this work, we performed the first comprehensive study on the molecular characteristics and functional properties of the Glu-B3h gene using the wheat cultivar CB037B and its Glu-B3 deletion line CB037C. The results showed that the Glu-B3h deletion had no significant effects on plant morphological or yield traits, but resulted in a clear reduction in protein body number and size and main quality parameters, including inferior mixing property, dough strength, loaf volume, and score. Molecular characterization showed that the Glu-B3h gene consists of 1179 bp, and its encoded B-subunit has a longer repetitive domain and an increased number of α-helices, as well as higher expression, which could contribute to superior flour quality. The SNP-based allele-specific PCR markers designed for the Glu-B3h gene were developed and validated with bread wheat holding various alleles at Glu-B3 locus, which could effectively distinguish the Glu-B3h gene from others at the Glu-B3 locus, and have potential applications for wheat quality improvement through marker-assisted selection.

Mapping a QTL conferring resistance to Fusarium head blight on chromosome 1B in winter wheat (Triticum aestivum L.).

Fusarium head blight (FHB) is one of the most devastating diseases of wheat (Triticum aestivum L.), and the development of cultivars with FHB resistance is the most effective way to control the disease. Yumechikara is a Japanese hard red winter wheat cultivar that shows moderate resistance to FHB with superior bread-making quality. To identify quantitative trait loci (QTLs) for FHB resistance in Yumechikara, we evaluated doubled haploid lines derived from a cross between Yumechikara and a moderate susceptible cultivar, Kitahonami, for FHB resistance in a 5-year field trial, and we analyzed polymorphic molecular markers between the parents. Our analysis of these markers identified two FHB-resistance QTLs, one from Yumechikara and one from Kitahonami. The QTL from Yumechikara, which explained 36.4% of the phenotypic variation, was mapped on the distal region of chromosome 1BS, which is closely linked to the low-molecular-weight glutenin subunit gene Glu-B3 and the glume color gene Rg-B1. The other QTL (from Kitahonami) was mapped on chromosome 3BS, which explained 11.2% of the phenotypic variation. The close linkage between the FHB-resistance QTL on 1BS, Glu-B3 and Rg-B1 brings an additional value of simultaneous screening for both quality and FHB resistance using the glume color.

The wheat transcription factor TaGAMyb recruits histone acetyltransferase and activates the expression of a high‐molecular‐weight glutenin subunit gene

Glutenin proteins in wheat (Triticum aestivum L.) flour confer unique viscoelastic properties to dough products and, therefore, the concentration and composition of the glutenin proteins determine its end-use value. However, the mechanisms governing the glutenin gene expression remain elusive. In this study, we report that wheat TaGAMyb activates the high-molecular-weight glutenin subunit genes (TaGLU) through recruiting the histone acetyltransferase GCN5. By sequencing the promoters of TaGLU-1 genes from 40 modern wheat cultivars, we identified eight types of TaGAMyb binding motifs and verified these by electrophoretic mobility shift assays. The number of TaGAMyb binding motifs in TaGLU-1 genes is correlated with the abundance of glutenin in different cultivars. Chromatin immunoprecipitation plus polymerase chain reaction (ChIP-PCR) analysis reveals that TaGCN5 directly targets the promoters of TaGLU-1 genes in wheat endosperm. We find that TaGAMyb physically interacts with the wheat histone acetyltransferase TaGCN5 and also interacts with Arabidopsis thaliana AtGCN5. TaGAMyb ectopically expressed in Arabidopsis binds to the TaGLU-1Dy promoter on a TaGLU-1Dy transgene and activates its expression. AtGCN5 also targets the TaGLU-1Dy transgene and is involved in the establishment of acetylation at H3K9 and H3K14. These results demonstrate that TaGAMyb plays a dual role in activating expression of glutenin gene by directly binding to the TaGLU promoter and by recruiting GCN5 to modulate histone acetylation during wheat endosperm development.

The distribution of cotransformed transgenes in particle bombardment-mediated transformed wheat.

Although particle bombardment is the predominant method of foreign DNA direct transfer, whether transgene is integrated randomly into the genome has not been determined. In this study, we identified the distribution of transgene loci in 45 transgenic wheat (Triticum aestivum L.) lines containing co-transformed high molecular weight glutenin subunit genes and the selectable marker bar using fluorescence in situ hybridization. Transgene loci were shown to distribute unevenly throughout the genome and incorporate into different locations along individual chromosomes. There was only a slight tendency towards the localization of transgenes in distal chromosome regions. High proportions of transgenes in separate plasmids integrated at the same site and only 7 lines had 2 or 3 loci. Such loci may not segregate frequently in subsequent generations so it is difficult to remove selectable markers from transgenic lines after regeneration. We also found that three transgene lines were associated with rearranged chromosomes, suggesting a the close relationship between particle bombardment-mediated transgene integration and chromosomal rearrangements.

Stripe rust resistance and dough quality of new wheat - Dasypyrum villosum translocation lines T1DL•1V#3S and T1DS•1V#3L and the location of HMW-GS genes.

The transfer of agronomically useful genes from wild wheat species into cultivated wheat is one of the most effective approaches to improvement of wheat varieties. To evaluate the transfer of genes from Dasypyrum villosum into Triticum aestivum, wheat quality and disease resistance was evaluated in two new translocation lines, T1DL•1V#3S and T1DS•1V#3L. We examined the levels of stripe rust resistance and dough quality in the two lines, and identified and located the stripe rust resistant genes and high molecular weight glutenin subunit (HMW-GS) genes Glu-V1 of D. villosum. Compared to the Chinese Spring (CS) variety, T1DL•1V#3S plants showed moderate resistance to moderate susceptibility to the stripe rust races CYR33 and Su11-4. However, T1DS•1V#3L plants showed high resistance or immunity to these stripe rusts. The genes for resistance to stripe rust were located on 1VL of D. villosum. In comparison to CS, the dough from T1DS•1V#3L had a significantly shorter developing time (1.45 min) and stable time (1.0 min), a higher weakness in gluten strength (208.5 FU), and a lower farinograph quality index (18). T1DL•1V#3S had a significantly longer developing time (4.2 min) and stable time (5.25 min), a lower weakness in gluten strength (53 FU) and a higher farinograph quality index (78.5). We also found that T1DS•1V#3L had reduced gluten strength and dough quality compared to CS, but T1DL•1V#3S had increased gluten strength and dough quality. The results of SDS-PAGE analysis indicated that Glu-V1 of D. villosum was located on short arm 1VS and long arm 1VL. These results prove that the new translocation lines, T1DS•1V#3L and T1DS•1V#3L, have valuable stripe rust resistance and dough quality traits that will be important for improving wheat quality and resistance in future wheat breeding programs.

Novel LMW glutenin subunit genes from wild emmer wheat (Triticum turgidum ssp. dicoccoides) in relation to Glu-3 evolution.

Four low-molecular-weight-isoleucine (LMW-i)-type and one novel chimeric (between LMW-i and LMW-methionine (m) types) low-molecular-weight glutenin subunit (LMW-GS) genes were characterized from wild emmer wheat (Triticum dicoccoides), designated as emmer-1 to emmer-5. All five LMW-GS genes possessed the same primary structure shared by other published LMW-GSs. The three genes emmer-1, emmer-3, and emmer-5 are similar, with the exception that emmer-3 and emmer-5 lost a few repeat motifs compared to emmer-1. Gene duplication and insertions/deletions of repeat motifs mediated through unequal crossing over may be responsible for the generation of these three Glu-3 alleles. Although the first residue of mature peptide of emmer-4 is isoleucine, it is not typical LMW-i-type LMW-GS. Phylogenetic analysis indicated that emmer-4 is located in the LMW-m subgroup, suggesting a closer relationship with LMW-m-type gene Y14104 of T. durum. Sequence alignment indicated that the emmer-4 is likely a chimeric gene generated by illegitimate recombination between LMW-i and LMW-m type. Unequal crossing over and illegitimate recombination are effective mechanisms for enriching both copy numbers and variations of LMW-GSs.

High-level expression of LMW-GS and α-gliadin genes promoted by the expressed tag sequence of 5′ end in Escherichia coli

Wheat storage protein genes, especially low molecular weight glutenin subunit (LMW-GS) and gliadin genes are difficult to be expressed in Escherichiacoli, mainly due to the presence of highly repetitive sequences. In order to establish a high efficiency expression system for these genes, five different expression plasmids combining with 9 genes, viz. 6 LMW-GS and 3 α-gliadin genes isolated from common wheat and related species, were studied for heterologous expression in E. coli. In this study, when an expressed tag sequence encoding signal peptide, His-S or GST-tag was fused to the 5′ end of LMW-GS or gliadin gene as the leading sequence, all recombination genes could be stably expressed at a high level. On the contrast, as expected, the inserted genes encoding mature protein failed without an expressed tag sequence. This result indicated that using expressed tag sequences as leading sequences could promote LMW-GS and gliadin genes to be well expressed in E. coli. Further transcriptional analysis by quantitative real-time PCR (qRT-PCR) showed transcription levels of recombination genes (e.g. GST-Glutenin, His-S-Glutenin and SP∗-His-Glutenin) were 4-fold to 33-fold higher than those of the LMW-GS genes, which suggested these expressed tag sequences might play an important role in stimulating transcription. The possible molecular mechanism under this phenomenon was discussed.

The detection of a de novo allele of the Glu-1Dx gene in wheat-rye hybrid offspring.

This study provides a link between a de novo gene and novel phenotype in wheat-rye hybrids that can be used as a model for induced de novo genetic variation. Wide hybridization can produce de novo DNA variation that may cause novel phenotypes. However, there is still a lack of specific links between changed genes and novel phenotypes in wide hybrids. The well-studied high-molecular-weight glutenin subunit (HMW-GS) genes in tribe Triticeae provide a useful model for addressing this issue. In this study, we investigated the feasibility of a wheat-rye hybridization method for inducing de novo phenotypes using the Glu-1Dx2.2 subunit as an example. We developed three hexaploid wheat lines with normal fertility and a Glu-1Dx2.2 variant, named Glu-1Dx2.2 (v) , derived from three F1 hybrids. The wild-type Glu-1Dx2.2 has two direct repeats of 295 bp length separated by an intervening 101 bp in its central repetitive region. In the mutant Glu-1Dx2.2 (v) , one copy of the repeats and the intervening sequence were deleted, probably through homology-dependent illegitimate recombination (IR). This study provides a direct link between a de novo allele and novel phenotype. Our results indicate that the wheat-rye method may be a useful tool to induce de novo genetic variations that broaden the genetic diversity for wheat improvement.

Characterisation of low molecular weight glutenin subunit genes from Pseudoroegneria spicata and Pd. strigosa.

We report the characterisation of nine novel low molecular weight glutenin subunit (LMW-GS) genes from two Pseudoroegneria species, Pd. spicata and Pd. strigosa. We found that all nine LMW-GS genes possess the same primary structure shared by other published LMW-GS. Five genes encode LMW-i type subunits, three encode LMW-m type subunits and one encodes a peptide similar to B-3 hordeins of Hordeum chilense. No LMW-s type subunit genes were found in Pseudoroegneria. One subunit, PSt24-LMW-2, contains six conserved cysteine residues, and the other eight subunits all contain eight cysteine residues. We show that one cysteine residue is located in the signal peptide of PSt24-LMW-1, suggesting a mature peptide containing only seven cysteine residues. Phylogenetic analysis indicates that the LMW-GS genes from the St genome cluster together and suggests a distant relationship with LMW-GS of the A and B genomes of wheat. Slippage/unequal crossing over and illegitimate recombination are effective mechanisms for enriching variations of seed storage proteins.

Characterization of high molecular weight glutenin subunit genes from the Ns genome of Psathyrostachys juncea.

The Ns genome of the genus Psathyrostachys possesses superior traits useful for wheat improvement. However, very little is known about the high molecular weight (HMW) subunits of glutenin encoded by the Ns genome. In this paper, we report the isolation of four alleles of HMW glutenin subunit gene from Psathyrostachys juncea. Sequence alignment data shows the four alleles have similar primary structure with those in wheat and other wheat-related grasses, with some unique modifications. All four sequences more closely resemble y-type, rather than x-type, glutenins. However, our results show three of the subunits (1Ns2-4) contain an extra glutamine residue in the N-terminal region not found on typical y-type subunits, as well as the x-type subunit specific sequence LAAQLPAMCRL. These three subunits likely represent an intermediate state in the divergence between x- and y-type subunits. Results also indicate that the Ns genome is more closely related to the St genome of Pseudoroegneria than any other Triticeae genomes.

Introgression of useful genes from Thinopyrum intermedium to wheat for improvement of bread‐making quality

AbstractTo study the influence of genes from Thinopyrum intermedium on traits affecting the bread‐making quality of wheat, two derivatives from a putative disomic addition line in cultivar ‘Vilmorin 27’ were used in cytological, biochemical and molecular characterization. Cytological analysis suggested that one of the derivatives (Line‐1) had a terminal deletion involving the long arm of chromosome 1D (2n = 42, Del‐1DL”), and the other (Line‐2) was a conventional addition line, but also carried the same deletion on chromosome 1D (2n = 44, Thi”+Del‐1DL”). Amplification and sequencing of high‐molecular‐weight glutenin subunit (HMW‐GS) genes coded by the Th. intermedium chromosome in Line‐2 indicated the presence of one x‐type with an extra cysteine and four (rather than one) unique y‐type genes. Rheological studies of Line‐1 showed significantly lower dough strength compared to ‘Vilmorin 27’, confirming the recognized role of Glu‐1D coded HMW‐GSs. Line‐2 showed significantly higher dough strength compared to the background cultivar, indicating a significant potential of Th. intermedium for improvement of bread‐making quality in wheat.

The wheat HMW-glutenin 1Dy10 gene promoter controls endosperm expression in Brachypodium distachyon

The grass species Brachypodium distachyon has emerged as a model system for the study of gene structure and function in temperate cereals. As a first demonstration of the utility of Brachypodium to study wheat gene promoter function, we transformed it with a T-DNA that included the uidA reporter gene under control of a wheat High-Molecular-Weight Glutenin Subunit (HMW-GS) gene promoter and transcription terminator. For comparison, the same expression cassette was introduced into wheat by biolistics. Histochemical staining for β-glucuronidase (GUS) activity showed that the wheat promoter was highly expressed in the endosperms of all the seeds of Brachypodium and wheat homozygous plants. It was not active in any other tissue of transgenic wheat, but showed variable and sporadic activity in a minority of styles of the pistils of four homozygous transgenic Brachypodium lines. The ease of obtaining transgenic Brachypodium plants and the overall faithfulness of expression of the wheat HMW-GS promoter in those plants make it likely that this model system can be used for studies of other promoters from cereal crop species that are difficult to transform.

ChAy/Bx, a novel chimeric high-molecular-weight glutenin subunit gene apparently created by homoeologous recombination in Triticum turgidum ssp. dicoccoides

High-molecular-weight glutenin subunits (HMW-GSs) are of considerable interest, because they play a crucial role in determining dough viscoelastic properties and end-use quality of wheat flour. In this paper, ChAy/Bx, a novel chimeric HMW-GS gene from Triticum turgidum ssp. dicoccoides (AABB, 2n=4x=28) accession D129, was isolated and characterized. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed that the electrophoretic mobility of the glutenin subunit encoded by ChAy/Bx was slightly faster than that of 1Dy12. The complete ORF of ChAy/Bx contained 1671bp encoding a deduced polypeptide of 555 amino acid residues (or 534 amino acid residues for the mature protein), making it the smallest HMW-GS gene known from Triticum species. Sequence analysis showed that ChAy/Bx was neither a conventional x-type nor a conventional y-type subunit gene, but a novel chimeric gene. Its first 1305 nt sequence was highly homologous with the corresponding sequence of 1Ay type genes, while its final 366 nt sequence was highly homologous with the corresponding sequence of 1Bx type genes. The mature ChAy/Bx protein consisted of the N-terminus of 1Ay type subunit (the first 414 amino acid residues) and the C-terminus of 1Bx type subunit (the final 120 amino acid residues). Secondary structure prediction showed that ChAy/Bx contained some domains of 1Ay subunit and some domains of 1Bx subunit. The special structure of this HMW glutenin chimera ChAy/Bx subunit might have unique effects on the end-use quality of wheat flour. Here we propose that homoeologous recombination might be a novel pathway for allelic variation or molecular evolution of HMW-GSs.

Expression of High Molecular Weight Glutenin Subunit genes correlated with gluten content in common wheat varieties from the highland of Ecuador

In this study we analyzed the performance of three wheat varieties in relation to gluten content under high-altitude growing conditions in the Andes of Ecuador. A field experiment was conducted at 3058 meters above sea level during 2009 using adapted wheat cultivar Cojitambo, cv. Carnavalero, and cv. Sibambe. Transcript accumulations of High Molecular Weight Glutenin Subunits (HMW-GS) genes were also evaluated during grain development using qRT-PCR. We recorded the expression profile of HMW-GS genes during 41 days and showed a coordinated pattern of induction with significant higher levels at 82–86 days. Transcript accumulation of 1Dx5, 1Dy10, 1Bx7, 1Ax1, and 1By9 genes were analyzed in more details during this period. The assay highlighted the specific contribution of 1Bx7, 1Dy10, and 1Dx5 during gluten formation in Ecuadorian wheat varieties. Under Andean highlands conditions, cv. Carnavalero showed the higher values of total agglomerated protein upon hydration and higher levels of expression of particular HMW-GS genes. The data suggest a correlation between wet gluten content and HMW-GS genes expression. Our study contributes to understand gluten formation in wheat endosperm under high-altitude conditions in the Andes.