Allelic Variation of High-Molecular-Weight Glutenin Genes in Triticum Species and Triticale (× Triticosecale Wittmack)
Penko Spetsov 1, *, Nadia Daskalova 2
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Aksakovo Center, Aksakovo, Varna region, 9154 Bulgaria
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Plant Production Department, Technical University, Varna, 9010 Bulgaria
* Correspondence: Penko Spetsov
Academic Editor: Pedro Martínez-Gómez
Collection: Genetic Testing
Received: February 27, 2024 | Accepted: April 01, 2024 | Published: April 09, 2024
OBM Genetics 2024, Volume 8, Issue 2, doi:10.21926/obm.genet.2402225
Recommended citation: Spetsov P, Daskalova N. Allelic Variation of High-Molecular-Weight Glutenin Genes in Triticum Species and Triticale (× Triticosecale Wittmack). OBM Genetics 2024; 8(2): 225; doi:10.21926/obm.genet.2402225.
© 2024 by the authors. This is an open access article distributed under the conditions of the Creative Commons by Attribution License, which permits unrestricted use, distribution, and reproduction in any medium or format, provided the original work is correctly cited.
Abstract
High-molecular-weight glutenin subunits (HMW-GS) encoded by alleles at the Glu-A1, Glu-B1, and Glu-D1 loci confer unique bread-making properties of common wheat (Triticum aestivum L.). The identification of HMW-GS is the prerequisite for pyramiding high-quality glutenin genes. The present review is designed to list all published HMW-GS alleles in Triticum species and triticale (A- and B genomes), focusing on methods for their identification. T. monococcum is characterized by 37 alleles at the Glu-1 locus versus four alleles in T. thaoudar and 39 in T. urartu. In total, 80 alleles at Glu-A1 of diploid Triticum species and about 42 alleles found in polyploid wheat landraces and varieties (4x and 6x), including triticale, were listed. Allelic variation at the Glu-B1 locus is divided into 3 groups: a – z, aa – az, and ba – ct, comprising 121 alleles, of which 26 subunits have unspecified alleles. At least 51 allelic variants at locus Glu-D1 of Triticum species were indicated, along with carriers of the species level. In addition, subunit-specific genetic loci have been tagged, facilitating molecular marker development of high-gluten wheat cultivars through marker-assisted breeding.
Keywords
HMW-glutenins; allelic variation; Triticum species; triticale
1. Introduction
Three components, high-molecular-weight glutenins (HMW-GS), low-molecular-weight glutenins (LMW-GS), and gliadins, make up gluten, the major protein in the endosperm of wheat seeds [1]. The elasticity of the dough depends on the HMW-GS, while the low-molecular-weight glutenins mainly provide the elasticity and extensibility of the dough. Gliadins are factors affecting dough extensibility. Since the 1970s, the influence of these significant gluten components on the baking process of bread wheat has received much attention [2,3].
Figure 1 Schematic diagram of the gene loci of HMW-GS in wheat 1A, 1B and 1D chromosomes.
The Glu-1 loci on the long arms of wheat group 1 (1A, 1B, 1D) chromosomes encode HMW-GS and are named Glu-A1, Glu-B1, and Glu-D1 based on their chromosome names. Two genes are linked together, encoding two different types of HMW-GS, x- and y-type subunits at each locus (Figure 1). In sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), x-type subunits generally have a slower electrophoretic mobility and higher molecular weight than y-type subunits. Each subunit is assigned a unique number that is part of the numbers of all subunits in SDS-PAGE. A single locus is indicated as the critical carrier from which the subunit is derived, and whether it is an x-type or y-type subunit. For clearer distinction, HMW-GS alleles can also be expressed as simple numbers, for example 5 + 10 (meaning Dx5 + Dy10) [4,5].
Hexaploid wheat is typically characterized by three to five subunits, and this variation is due to both cultivar protein composition and presence of silent genes in the genotype. The Glu-A1 locus encodes one subunit or none, Glu-B1 two or one, and Glu-D1 two subunits. In the 1980s, the Glu-A1 locus was represented by three alleles, namely a, b, and c, versus eleven (a – k) at Glu-B1 and six (a – f) at the Glu-D1 locus [4,6]. The last mentioned one has the strongest effect on wheat quality, followed by loci Glu-B1 and Glu-A1. The variation in the protein composition is usually due to the high-molecular-weight glutenins, regardless of their small amount in the seeds, about 10%. Therefore, increasing the variation of HMW-GS alleles will potentially lead to more attention of researchers to wheat grain quality in crops breeding [7,8]. This article aims to review all published HMW-glutenin alleles in Triticum species, including triticale A- and B genomes, focusing on methods for their identification and practical breeding aspects of recent molecular advances.
2. Allelic Variation at Glu-A1 Locus
2.1 Diploid Triticum Species
Research on the HMW-GS in the A genome of diploid and hexaploid wheat species has begun in the second half of the last century [9]. The HMW subunits of T. monococcum ssp. boeoticum had a major x-subunit of slow mobility and several less prominent y-subunits of greater mobility, all of which fall within the mobility range of HMW subunits reported for bread wheat. In T. monococcum ssp. monococcum the range of the banding patterns for HMW subunits was similar to that of ssp. boeoticum. However, two accessions containing y-subunits were null for x-subunits. The HMW subunit banding patterns of T. urartu accessions were distinct from those of T. monococcum. All of them contained one major, and most contained one major y-subunit. The active genes for y-subunits, if transferred to bread wheat, may be useful in improving bread-making quality. 30 different alleles were described (a – z, aa – ae) at the Glu-A1m locus (Table 1) [10]. The only T. sinskajae accession had the allele o, as did some specimens of cultivated einkorn wheat. Researchers found three allelic variants (alleles a, b and c) [11], and seven subunits, three for Glu-A1x, and four for Glu-A1y [12]. A wider variation for the Glu-A1x was detected [13,14,15]. The spectrum of A1y-subunits was extended by 1Ay8* and 1Ay12* [16] and 1Ay8.2 and 1Ay8.3 [17,18]. At present, the A genome of T. monococcum (incl. ssp. monococcum, atriaristatum, flavescens, halbohornemanii, hornemanii, laetissimum, macedonicum, pseudomacedonicum, nigricultum, pseudoflavescens, sofianum, and vulgare) is characterized by 37 alleles with published 16 x-type and 8 y-type subunits.
1Ay-subunits are of great interest because they are always silent in bread wheat. Four y-type subunits in T. monococcum ssp. aegilopoides differed from those of T. urartu (Table 1) [19]. Seven y-type subunits in this species, named with Roman numbers, were additionally detected [15]. Wild diploid wheat exhibited active Ay-subunits, and consequently, they could be good sources for increasing the number of alleles encoding active subunits at the Glu-A1 locus. This procedure was exploited with two lines of T. boeoticum ssp. thaoudar for introducing active Ay subunits into common wheat [20] to increase gluten strength. This was also observed in a cross between a T. urartu accession and durum wheat cv. Yavaros and 1Ax2* + 1Ay-null subunits transferred from T. boeoticum through synthetic hexaploid wheat 8A-Tb into durum background [21,22]. Due to the single accession of T. sinskajae involved in investigations, the published data are scarce. Summarizing, two Glu-A1 allelic variants were described in T. thaoudar coding for subunits 39 – 42.
Table 1 HMW-GS variation at Glu-A1 in diploid Triticum species.
Different authors used different nomenclature of Glu-A1 allelic variation in T. urartu. Seventeen alleles for the Glu-Au1 locus (ac – as) were published [23,24]. A recent study reported different electrophoretic mobility among the 1Ax1 subunits of T. urartu compared to those of bread wheat varieties Xiaoyan-54 and Cheyenne [25]. Four 1Ax subunits in 46 accessions showed slower electrophoretic mobility than the 1Ax2* present in Cheyenne. The electrophoretic mobility of the 1Ay subunits was faster than the 1Dy10 subunit of cultivated wheat with eleven 1Ax (a – k) and eight 1Ay (a – h) alleles, resulting in 18 HMW-GS genotypes, U1-U18 (Table 1). It was evident that the 1Ay genes from T. urartu were closer to those from T. dicoccum and T. aestivum than those from T. monococcum ssp. aegilopoides [19]. Finally, 39 HMW Glu-1A alleles in T. urartu were detected.
2.2 Tetraploid and Hexaploid Triticum Species
Early studies initially identified several alleles at the Glu-1 loci as 3, 11, and 6 for Glu-1A, Glu-1B, and Glu-1D, respectively [4]. The authors compared the subunits derived from the four nomenclature systems and recommended allele designations for the three loci. Since this catalog of alleles was published at Glu-1 loci, more alleles have been identified [26,27,28,29]. One adopted nomenclature [30] for the alleles encountered in T. dicoccum was used for the new ones in T. durum [31]. The authors reported seven HMW subunits of Glu-1A alleles in the 520 durum wheat varieties. To date, 31 alleles at the Glu-A1 locus plus 11 others encoding named subunits have been published (Table 2).
Table 2 HMW-GS variation at Glu-A1 locus in Triticum species (4x and 6x) and triticale.
Allelic variation at the Glu-A1 locus affects grain end-use quality. A new high-molecular-weight glutenin subunit at the Glu-A1 locus (designated 21*) has been published that is of better quality than the common allelic variants 2* and 1 [44]. Using the electrophoretic, reversed-phase high-performance liquid chromatographic (RP–HPLC) analyses and polymerase chain reaction (PCR), the authors revealed genes encoding the subunits 21* and 21*y [45]. When the two y-type subunits were transferred into the Australian bread wheat cultivar Livingston, one of them (1Ay21*) showed a higher quality potential than 1AyT1. According to the authors, both alleles increased grain protein content, dough properties, and bread loaf volume [47].
Some molecular markers, such as allele-specific polymerase chain reaction (AS-PCR) based on single nucleotide polymorphisms (SNPs), have proven to be a rapid and efficient screening tool for desirable HMW-GS. Various genes in the Glu-A1 locus, such as 1Ax2*, 1Ax2.1*, 1Ax1, and 1Ax, can be selected by AS-PCR markers for efficient use in breeding. Three locus-specific sequence-tagged locus markers showed distinctive features for marking selected Glu-A1 and Glu-D1 alleles. For example, UMN19 marker was created to differentiate Glu-A1b (Ax2*) from Glu-A1a (Ax1) on Glu-A1 locus [7,64,65]. Additionally, some primers have been described to precisely detect the 2* subunit and discriminate it from null and 1 glutenin subunit [65,66]. Wheat lines with Glu-A1a or Glu-A1b showed higher dough strength than lines with null allele Glu-A1c [67]. The use of Glu-A1 markers to screen wheat cultivars worldwide has shown that more than 50% of cultivars from different countries carry Glu-A1b. Several end-use seed quality markers are diagnostic as they have been established based on the sequences of the relevant genes [51,68]. A new set of DNA markers helped to establish 11 haplotypes at the Glu-A1 locus (H1 to H11) in three wheat species [69]. The major haplotypes in tetraploid wheat (T. turgidum) are H1, H8, and H9, containing both 1Ax and 1Ay subunits. The developed DNA markers are helpful in studying molecular variation and evolutionary mechanisms of orthologous Glu-A1 regions in common wheat and related species.
A novel x-type HMW-GS encoded by the Glu-A1 locus was published as 2•• [54]. The authors describe its structure and function as highly favorable for grain quality, equal to subunit 2*. Subunit 2•• was later discovered in Spanish wheat cultivars [70]. For easy and fast identification of 2••, a PCR screening method was created. Alignment comparison of 2•• with 2* shows an 18 bp deletion present in the nucleotide sequence of 2*, but not in the 2•• sequence. This subunit scored higher qualitative values than protein 2*: high sedimentation volume, the low percentage difference between maximum peak height and 3 min post-peak height, and higher mixograph values. New subunits (1Ax2.2 and 1Ay) were recorded in the wild emmer accession D97. The 1Ax1.2 protein fraction was introduced into one of two newly obtained lines from the cross of the common wheat variety Chuannong 16 with the wild strain emmer [61]. Adding to the list of new genes is Glu-A1x, found in native wheat cultivars, encoding a subunit called 1‴. Recently, in T. dicoccoides acc. K5199, another subunit, 1AxTd, was identified using primers to reveal its sequence of nucleotides [58,62].
3. Allelic Variation at Glu-B1 Locus
3.1 HMW-GS Alleles a – z
In this group, 26 alleles were published for about 40 years. At first, 11 alleles (a – k) were revealed in T. aestivum, compared to subunit designations of various authors [4]. Another 9 alleles (I – IX) annotated by the proposed system in durum and common wheat cultivars were added, making their total number 20 [30,31]. Later, alleles m, n, o, q, x, and y encoding I, II, III, V, VII, and VIII subunits were listed (Table 3). The established o and s alleles in bread wheat (6 + 22 and By18* subunits) were in conflict with the previously published s allele expressing 7 + 11 subunits [37,42]. There is no information for two alleles (t and v) about their subunits. The Glu-B1e allele is responsible for Bx20 or 20x + 20y [27,46].
The following four methods, SDS-PAGE, RP-HPLC, high-performance capillary electrophoresis (HPCE), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) were employed to analyze the HMW-GS compositions of 60 genotypes belonging to different 4x- and 6x-wheats [5].
Table 3 HMW-GS alleles a – z at Glu-B1 locus in Triticum species and triticale.
A key objective was to compare and evaluate these methods regarding resolution, sensitivity, accuracy, and throughput. Comparative analysis demonstrated that each methodology has its advantages and disadvantages. The materials expressed a variety of 17 Glu-B1 alleles, 9 of which belong to the group of a – z. Bx7 is one of the most critical subunits encoded by the Glu-B1 locus and related to baking quality. Three variants can be distinguished among Bx7: Bx7, Bx7* and Bx7OE. Novel DNA markers for accurate discrimination between the Glu-B1 locus subunits Bx7 and Bx7* were described [56,83]. The Glu-B1 locus was more variable in durum wheat, with fifteen alleles represented, of which Glu-B1b (7 + 8), -B1d (6 + 8), and -B1e (20 + 20) were the most frequently occurring [71,76].
3.2 HMW-GS Alleles aa – az
This group comprised 24 alleles, of which ab, ax, ay and az encoded XI, XV, XVI and XVII subunits found in tetraploid wheat, respectively [27,84]. There are eight single bands in the list, that is Bx6, Bx7', Bx7*, Bx13, Bx18*, Bx37, By8, and By18, and one null allele, Glu-B1ah (Table 4). Two primer sets (P3 and P4) allowed for precise determination of the occurrence of individual x-type subunits. Bx7* is the most frequently identified subunit in wheat and occurred in 65% of the tested cultivars. Bx7 was identified in 25% of genotypes and Bx7 or Bx7* (not precisely identified) - 7.5%. A wide distribution of the Bx7* in wheat was recorded [76,83,85]. The Bx6 subunit is associated with poor baking quality and occurs with a relatively low frequency [86]. There were two variants of Glu-B1b (7 + 8), Glu-B1u (7* + 8) and Glu-B1al (7OE + 8*), that could be differentiated by the presence of an 18 bp indel at a repetitive domain of hexapeptide motif [87]. The Glu-B1al lines with Bx7OE subunit well identified by SDS-electrophoresis, had higher dough strength than the lines with other Glu-B1 alleles, and markers have been designed [88,89]. A survey of diploid, tetraploid, and hexaploid wheat using SDS-PAGE showed that the overexpressed phenotype of Glu-B1a (Bx7) and Glu-B1al, only occurred in T. turgidum and T. aestivum [67,89,90].
Table 4 HMW-GS alleles aa - az at Glu-B1 locus in Triticum species and triticale.
Three y-type subunits were identified at the Glu-B1 locus. Primer sets were designed and used for 1By subunit determination [104]. A comparison of the results obtained for primers P5 and P6 indicated that the By9 subunit was present in 59% of cultivars studied against twice less content of By8 and By-null in them. The researchers drew attention to the discrimination of Bx7, Bx7* and Bx7OE. The allele Glu-B1i encoding 17 + 18 subunits has been considered the most significant effect on gluten quality among 11 Glu-B1 alleles in bread wheat [105]. Two SNP-based AS-PCR markers for 1By18 gene identification were developed and validated using many bread wheat varieties and RILs [68]. A set of 17 SNP markers representing the most frequent SDS-PAGE alleles at each locus was designed [46]. Four markers at the Glu-B1 locus constituted a valuable toolbox for breeding wheat to improve end-use quality.
3.3 HMW-GS Alleles ba – ct
The section contains 46 alleles, of which 6 (Glu-B1bl, -bw, -bz, -ck, -cn, and -cp) encode single bands (Table 5). Data for -bk/be, -bl/bf, and -bm/bg alleles in the wheat gene catalog [27] and other studies [51,52] are conflicting. Similar situations in Glu-B1bh encoded by 13 + 22 or 13 + 22* subunits [27,52] and Glu-B1cp characterized by 20* or 14* subunits [50,106]. The Glu-B1al gene (Bx7OE + By8*) improves dough strength over the more common allele Glu-B1b (7 + 8) and another promising allele Glu-B1i (17 + 18) [107]. Subunit Bx7OE is found only in high-gluten wheat materials.
Table 5 HMW-GS alleles ba - ct at Glu-B1 locus in Triticum species and triticale.
SDS-PAGE has difficulty distinguishing HMW glutenins with similar electrophoretic mobilities, such as By8 and By8* [104]. Multiplex PCR can simultaneously detect different target genes in one PCR reaction, improving efficiency and reducing costs compared to single PCR markers. Positive results were obtained when multiplex PCR detected the presence of Ax2*, Bx7OE, and Dx5 [87,120] on an agarose gel-based codominant attachment region marker for the Bx7OE subunit homozygosity test at the Glu-B1 locus [7]. Researchers used a combined method (MALDI-TOF–MS and genotyping markers) to identify lines containing 1Bx7OE from an experiment with 217 wheat genotypes [117]. This approach is of practical importance when the goal is to select plants with the Glu-B1al allele for creating lines with increased dough strength in the wheat breeding programs.
Different authors marked differently the subunit expression of Glu-B1al: 7 + 8*, 7OE + 8, and 7OE + 8* [46,98,121]. The allele encoding the overexpression of the 7OE subunit was previously found to have a large positive influence on bread-making quality [97,122]. MALDI-TOF-MS is a powerful technique to rapidly identify the diversity of HMW-GS alleles at the Glu-B1 locus. Its high resolution also led to the identification of a novel HMW-GS 7b* + 8 in the Japanese germplasm Eshimashinriki [98], as well as the discrimination of protein subunits 7OE, 8a* and 8b* associated with superior seed quality, which was not possible by the use of SDS-PAGE method.
Glu-B1al is not the only allele in Glu-B1 with a duplication of the x-type glutenin gene. Glu-B1al, Glu-B1br, and Glu-B1bs provide overexpression of subunits of the same size and electrophoretic mobility as Bx7, but Glu-B1br appear to differ from the others in its effect on glutenin polymerization. The similarity in the DNA sequences of the three alleles, as well as the identical duplication linkages in the three alleles to the same places found in diploid, tetraploid, and hexaploid Triticum species [88], indicate that these alleles originated from a common ancestor. In wheat, the Argentinian wheat cultivar Klein Universal II has been shown to be a Glu-B1al donor in several common wheat cultivars [87]. The VQ0437 genotype probably inherited Glu-B1bs from the CD87 variety [114].
The Glu-B1ch (7 + 22) allele was reported in one Mediterranean strain and three Iranian landraces [100]. Recent authors have also linked Glu-B1ch to low gluten quality. Conversely, some haplotypes carrying 7 + 15 or 7 + 22 banding patterns gave excellent glutenin profiles with elevated SDSS (sodium dodecyl sulfate micro sedimentation assay) values. Their use in selection should be more careful in durum wheat breeding programs [82]. The Italian Polesine (14 + 22*) has a unique protein pattern associated with low gluten quality but with a high grain protein content value. Subunit 22* has been published as a rare protein variant [100].
Another unique banding pattern (6* + 15*) was obtained in the local variety Haurani. A previous study described this wheat variety's 6 + 16 pairs [123]. The authors found that subunit 6* had a higher mobility than subunit 6 in the SDS-PAGE. Various quality parameters were investigated over 2 years to establish that the 6* + 15* subunits could be a helpful breeding resource for grain quality. A new combination of subunits at the Glu-B1 locus (6 + 20y) was published, found only in the Italian cultivar Capeiti 8. However, previous studies reported different patterns for this cultivar, such as 20x + 20y and 7 + 8 [93]. The 6 + 20y pair was not evaluated phenotypically, which also applies to the 14 + 22*, 6 + 20y, and 6* + 15* glutenins, tentatively designated as -B1cr, -B1ct, and -B1cs alleles, respectively [27].
Interesting subunits were identified in the European spelt wheat, such as 1By19*. The allele structure was analyzed by cloning and sequencing. SNP-based molecular markers have been developed using different F2 populations derived from crosses between spelt and bread wheat cultivars and recombinant inbred lines [51].
3.4 HMW-GS Unspecified Alleles
This group includes 27 subunit patterns involving 12 single bands. Six of them are y-type subunits, By8*, By8.1, By8.1*, By16*, By20, and ByTd (Table 6).
Table 6 HMW-GS subunits at Glu-B1 locus with unspecified alleles.
The germplasms used generally expressed good match between the MALDI-TOF-MS determined molecular masses and these deduced from the coding sequences [5]. The authors compared lines with different subunits at Glu-1 loci, demonstrating that MALDI-TOF-MS is suitable for screening HMW glutenins and identifying new genotypes. In Syrian durum genotypes, Glu-B1b and Glu-B1d were the most frequent alleles, and the 6 + 15 subunit was found at high frequencies [124]. A comparison showed the effects of several Glu-B1 subunits, including 6.1 + 22, on dough strength (W) and tenacity (P) wheat flour. Three other subunits, 1Bx14, 14 + 19 and 23 + 8 occurred less frequently, between 0.2 and 0.5 percent. Two subunits, 6 + 8** and By8* were very scarce, found in Asian wheat genotypes, while 1Bx14.1 was designated as a new subunit [42].
The Chinese wheat landraces contained novel alleles (1Bx7.1* and 1By8.1*), indicating that this group was also a potential resource for improving wheat quality [78,128]. A novel high-molecular-weight glutenin subunit encoded by the Glu-1B locus was identified in the French genotype Bagou, named 1Bx6.5. This subunit differed in SDS-PAGE from the well-known 1Bx6 and 1Bx7 subunits, encoded at this locus [127]. Several other subunits with unspecified alleles are shown in Table 6.
4. Allelic Variation at Glu-D1 Locus
At least 51 alleles were identified at the Glu-D1 locus of hexaploid Triticum species (Table 7). Carriers of alleles involved T. aestivum (exclusively wheat landraces, historical and modern varieties), T. macha, T. compactum, T. spelta, T. sphaerococcum, and T. petropavlovskyi. Aegilops tauschii (DD, 2n = 14) genes representing 42 alleles (t, x, y, z, aa – ak, aq – az, ba – bn, and br – bt) were listed here without subunits following the accepted order [27]. There were several single subunits: 1Dx2, 2.2*, 5, 36, 38 and 1Dy subunits, 10, 10.1, 11, 12, 12*, 12.1, 12.1* and 12.2. Allele i encoded null at Glu-D1-1 as found in Nap Hal variety expressing both high protein and high lysine contents [27,129], and in cultivar Lontoi from Finland [46]. The first six alleles (a – f) were identified earlier [4]. Some conflicts were found in Glu-D1am allele (subunits 2 + 12'or 2 + 12*) and Glu-D1br (2.8 + 12 or 5*t + 10.1t).
Table 7 HMW-GS allelic variation at Glu-D1 locus.
In the past decades, various techniques have been developed to characterize the allelic variation of HMW-GS. These include SDS-PAGE, two-dimensional electrophoresis (2-DE), PCR, high-performance capillary electrophoresis (HPCE), RP-HPLC, MALDI-TOF-MS, and lab-on-a-chip capillary electrophoresis [5,130,145]. MALDI-TOF-MS was characterized as an accurate and high-throughput method for determining the HMW-GS composition of wheat varieties. Until now, only five active Glu-1Dy genes have been cloned and characterized from bread wheat. The allelic variation at the Glu-1 locus in 485 Chinese wheat landraces using MALDI-TOF-MS method characterized and identified several novel Glu-1D subunits [60,143]. Researchers successfully separated 1Dx subunits 2, 2.2, 5, and 1Dy10, 12 in HMW-GS profiles of 38 Korean wheat cultivars [130]. The identified HMW-GS of each variety precisely agreed with the results previously obtained using RP-HPLC combined with SDS-PAGE [146].
To facilitate early selection of HMW-GS alleles in breeding programs, DNA-based molecular markers were developed by KASPar assays with a high degree of concordance between HMW-GS identified by SDS-PAGE and molecular markers, despite several discrepancies between the two methods [46]—the Mk-D1-2-1 marker at Glu-D1-2 distinguished subunits 10 and 12 as in SDS-PAGE identification. Further, a new agarose gel-based multiplex PCR system for detecting three high-quality HMW-GS of Ax2*, Bx7OE, and Dx5 was established. These multiplex markers will effectively develop strong-gluten wheat cultivars via marker-assisted breeding [7,147].
Wheat lines missing one subunit at Glu-D1, either x- or y-subunit, attract great interest for the potential grain quality [148]. The effect of subunit Dy10 on wheat dough properties and end-use quality was studied by generating and analyzing a deletion mutant with the Dy-null allele. The Dy-null allele might be exploited by wheat breeding programs [149].
5. Conclusion
The analysis and characterization of HMW-GS banding patterns in wild Triticum specimens and landraces of wheat and their comparison with cultivated wheat is a successful strategy to introduce exotic genes into elite germplasms to improve wheat grain quality. Production of lines with different x- and y-subunits through the pyramiding of subunit-specific genetic loci may be facilitated by molecular markers for the specific glutenin fraction variants. Breeders can now efficiently select the desirable subunit in the early generations of wheat quality crosses using AS-PCR markers. In practice, it is preferable to have more information about subunits for each gene related to quality in individual forms and the subsequent evaluation of these proteins for best quality parameters. This will increase the selection efficiency and facilitate the creation of elite wheat and triticale lines with high glutenin subunit contents for quality improvement in breeding programs.
Author Contributions
The authors contributed to the study conception and design. Alleles at Glu-A1 and Glu-B1 loci were performed by P. Spetsov, and alleles at Glu-D1 – by N. Daskalova. The first draft of the manuscript was written by PS and both authors commented on the final version of the manuscript.
Funding
The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.
Competing Interests
The authors have no relevant financial or non-financial interests to disclose.
References
- Shewry PR. Wheat. J Exp Bot. 2009; 60: 1537-1553. [CrossRef]
- Branlard G, Giraldo P, He Z, Igrejas G, Ikeda TM, Janni M, et al. Contribution of genetic resources to grain storage protein composition and wheat quality. In: Wheat quality for improving processing and human health. Cham, Switzerland: Springer International Publishing; 2020. pp. 39-72. [CrossRef]
- Guzmán C, Crossa J, Mondal S, Govindan V, Huerta J, Crespo-Herrera L, et al. Effects of glutenins (Glu-1 and Glu-3) allelic variation on dough properties and bread-making quality of CIMMYT bread wheat breeding lines. Field Crops Res. 2022; 284: 108585. [CrossRef]
- Payne PI, Lawrence GJ. Catalogue of alleles for the complex gene loci, Glu-A1, Glu-B1, and Glu-D1 which code for high molecular-weight subunits of glutenin in hexaploid wheat. Cereal Res Commun. 1983; 11: 29-35.
- Gao L, Ma W, Chen J, Wang K, Li J, Wang S, et al. Characterization and comparative analysis of wheat high molecular weight glutenin subunits by SDS-PAGE, RP-HPLC, HPCE, and MALDI-TOF-MS. J Agric Food Chem. 2010; 58: 2777-2786. [CrossRef]
- Payne PI, Nightingale MA, Krattiger AF, Holt LM. The relationship between HMW glutenin subunits composition and bread-making quality of British grown wheat varieties. J Sci Food Agric. 1987; 40: 51-65. [CrossRef]
- Yao C, Zhang C, Bi C, Zhou S, Dong F, Liu Y, et al. Establishment and application of multiplex PCR systems based on molecular markers for HMW-GSs in wheat. Agriculture. 2022; 12: 556. [CrossRef]
- Mohamed IE, Oe H, Kamal NM, Mustafa HM, Gorafi YS, Tahir IS, et al. Enhancing wheat flour quality through introgression of high-molecular-weight glutenin subunits from Aegilops tauschii accessions. Front Sustain Food Syst. 2022; 6: 887795. [CrossRef]
- Waines JG, Payne PI. Electrophoretic analysis of the high-molecular-weight glutenin subunits of Triticum monococcum, T. urartu, and the A genome of bread wheat (T. aestivum). Theor Appl Genet. 1987; 74: 71-76. [CrossRef]
- Saponaro C, Pogna NE, Castagna R, Pasquini M, Cacciatori P, Redaelli R. Allelic variation at the GliA1m, Gli-A2m and Glu-A1m loci and breadmaking quality in diploid wheat Triticum monococcum. Genet Res. 1995; 66: 127-137. [CrossRef]
- Alvarez JB, Moral A, Martin LM. Polymorphism and genetic diversity for the seed storage proteins in Spanish cultivated einkorn wheat (Triticum monococcum L. ssp. monococcum). Genet Resour Crop Evol. 2006; 53: 1061-1067. [CrossRef]
- Şan SK, Özbek Ö, Eser V, Taşkin BG. Polymorphism in seed endosperm proteins (gliadins and glutenins) of Turkish cultivated einkorn wheat (Triticum monococcum ssp. monococcum) landraces. Cereal Res Commun. 2015; 43: 108-122. [CrossRef]
- Li HY, Li ZL, Zeng XX, Zhao LB, Chen G, Kou CL, et al. Molecular characterization of different Triticum monococcum ssp. monococcum Glu-A1mx alleles. Cereal Res Commun. 2016; 44: 444-452. [CrossRef]
- Li ZL, Li HY, Chen G, Liu XJ, Kou CL, Ning SZ, et al. Molecular characterization of seven novel Glu-A1mx alleles from Triticum monococcum ssp. monococcum. Cereal Res Commun. 2017; 45: 647-654. [CrossRef]
- Huertas-García AB, Castellano L, Guzmán C, Alvarez JB. Potential use of wild einkorn wheat for wheat grain quality improvement: Evaluation and characterization of Glu-1, Wx and Ha loci. Agronomy. 2021; 11: 816. [CrossRef]
- Guo XH, Wu BH, Hu XG, Bi ZG, Wang ZZ, Liu DC, et al. Molecular characterization of two y-type high molecular weight glutenin subunit alleles 1Ay12* and 1Ay8* from cultivated einkorn wheat (Triticum monococcum ssp. monococcum). Gene. 2013; 516: 1-7. [CrossRef]
- Li ZL, Li HG, Chen G, Kou CL, Ning S, Yuan Z, et al. Characterization of a novel y-type HMW-GS with eight cysteine residues from Triticum monococcum ssp. monococcum. Gene. 2015; 573: 110-114. [CrossRef]
- Chen G, Zhang MH, Liu XJ, Fu JY, Li HY, Hao M, et al. Characterization of an expressed Triticum monococcum Glu-A1y gene containing a premature termination codon in its C-terminal coding region. Cereal Res Commun. 2018; 46: 201-210. [CrossRef]
- Jiang QT, Wei YM, Wang F, Wang JR, Yan ZH, Zheng YL. Characterization and comparative analysis of HMW glutenin 1Ay alleles with differential expressions. BMC Plant Biol. 2009; 9: 16. [CrossRef]
- Rogers WJ, Miller TE, Payne PI, Seekings JA, Sayers EJ, Holt LM, et al. Introduction to bread wheat (Triticum aestivum L.) and assessment for bread-making quality of alleles from T. boeoticum Boiss. ssp. thaoudar at Glu-A1 encoding two high-molecular subunits of glutenin. Euphytica. 1997; 93: 19-29. [CrossRef]
- Alvarez JB, Caballero L, Nadal S, Ramirez MC, Martín A. Development and gluten strength evaluation of introgression lines of Triticum urartu in durum wheat. Cereal Res Commun. 2009; 37: 243-248. [CrossRef]
- Daskalova N, Doneva S, Stanoeva Y, Belchev I, Spetsov P. Progress in tetraploid wheat breeding through the use of synthetic hexaploid amphiploids. Cereal Res Commun. 2019; 47: 157-169. [CrossRef]
- Caballero L, Martin MA, Alvarez JB. Allelic variation for the high- and low molecular-weight glutenin subunits in wild diploid wheat (Triticum urartu) and its comparison with durum wheats. Aust J Agric Res. 2008; 59: 906-910. [CrossRef]
- Caballero L, Martín MA, Alvarez JB. Genetic diversity forseed storage proteins in Lebanon and Turkey populations of wild diploid wheat (Triticum urartu Thum. ex Gandil.). Genet Resour Crop Evol. 2009; 56: 1117-1124. [CrossRef]
- Wang X, Luo GB, Yang WL, Li Y, Sun J, Zhan K, et al. Genetic diversity, population structure and marker-trait associations for agronomic and grain traits in wild diploid wheat Triticum urartu. BMC Plant Biol. 2017; 17: 112. [CrossRef]
- Daskalova N, Doneva S, Stanoeva Y, Spetsov P. Characterisation of synthetic hexaploid wheat (BBAuAuAmAm) and its potential use in wheat breeding. Zemdirbyste Agric. 2022; 109: 237-244. [CrossRef]
- McIntosh RA, Yamazaki Y, Dubcovsky J, Rogers WJ, Morris C, Appels R, et al. Catalogue of gene symbols for wheat: 2013–2014. Proceedings of the 12th International Wheat Genetics Symposium; 2013 September 8-13; Yokohama, Japan.
- McIntosh RA, Hart GE, Gale MD. Catalogue of gene symbols for wheat (supplement). Ann Wheat Genet Newsl. 1994; 40: 362-375.
- Yang ZJ, Li GR, Feng J. Molecular cytogenetic characterization and disease resistance observation of wheat—Dasypyrum breviaristatum partial amphiploid and its derivatives. Hereditas. 2005; 142: 80-85. [CrossRef]
- Vallega V, Waines JG. High molecular weight glutenin subunit variation in Triticum turgidum var. dicoccum. Theor Appl Genet. 1987; 74: 706-710. [CrossRef]
- Branlard G, Autran JC, Monneveux P. High molecular weight glutenin subunit in durum wheat (T. durum). Theor Appl Genet. 1989; 78: 353-358. [CrossRef]
- Amiour N, Dardevet A, Khelifi D, Bouguennec A, Branlard G. Allelic variation of HMW and LMW glutenin subunits, HMW secalin subunits and 75K gamma-secalins of hexaploid triticale. Euphytica. 2002; 123: 179-186. [CrossRef]
- Rasheed A, Mahmood T, Kazi AG, Ghafoor A, Mujeeb-Kazi A. Allelic variation and composition of HMW-GS in advanced lines derived from D-genome synthetic hexaploid/bread wheat (Triticum aestivum L.). J Crop Sci Biotechnol. 2012; 15: 1-7. [CrossRef]
- Kozub NA, Boguslavskii RL, Sozinov IA, Tverdokhleb YV, Xynias IN, Blume YB, et al. Alleles at storage protein loci in Triticum spelta L. accessions and their occurrence in related wheats. Cytol Genet. 2014; 48: 33-41. [CrossRef]
- López-Fernández M, Pascual L, Faci I, Fernández M, Ruiz M, Benavente E, et al. Exploring the end-use quality potential of a collection of Spanish bread wheat landraces. Plants. 2021; 10: 620. [CrossRef]
- Alvarez JB, Caballero L, Martín LM. Variability for morphological traits and high molecular weight glutenin subunits in Spanish spelt lines. Plant Genet Resour. 2007; 5: 128-130. [CrossRef]
- Gupta RB, Shepherd KW. Inheritance of novel high-molecular-weight glutenin subunits in the Tunisian bread wheat BT-2288. Genome. 1988; 30: 442-445. [CrossRef]
- Lukow OM, Payne PI, Tkachuk R. The HMW glutenin subunit composition of Canadian wheat cultivars and their association with bread-making quality. J Sci Food Agric. 1989; 46: 451-460. [CrossRef]
- Ng PK, Pogna NE, Mellini F, Bushuk W. Glu-1 allele compositions of the wheat cultivars registered in Canada. J Genet Breed. 1989; 43: 53-59.
- Chacón EA, Vázquez FJ, Giraldo P, Carrillo JM, Benavente E, Rodríguez-Quijano M. Allelic variation for prolamins in Spanish durum wheat landraces and its relationship with quality traits. Agronomy. 2020; 10: 136. [CrossRef]
- Pogna NE, Mellini F, Beretta A, Dal Belin Peruffo A. The high-molecular-weight glutenin subunits of common wheat cultivars grown in Italy. J Genet Breed. 1989; 43: 17-24.
- Famina AA, Malyshev SV, Shylava AA, Liaudanski AO, Urbanovich OY. Study of allelic diversity of the genes encoding high molecular weight glutenins in wheat varieties and lines utilized in the breeding process in the Republic of Belarus using PCR markers. Cytol Genet. 2019; 53: 282-293. [CrossRef]
- Rogers WJ, Payne PI, Miller TE, Holt LM, Law CN, Sayers EJ, et al. Introduction to hexaploid wheat and assessment for bread-making quality of a Glu-A1 locus from Triticum thaoudar encoding two high-molecular-weight subunits of glutenin. Proceedings of the XII Eucarpia Congress Science for Plant Breeding; 1989 February 27-March 4; Göttingen, Germany. Gottingen: Leibniz Insitute of Plant Genetics and Crop Plant Research.
- Johansson E, Henriksson P, Svensson G, Heneen WK. Detection, chromosomal location and evaluation of the functional value of a novel high Mr glutenin subunit found in Swedish wheats. J Cereal Sci. 1993; 17: 237-245. [CrossRef]
- Margiotta B, Urbano M, Colaprico G, Johansson E, Buonocore F, D’Ovidio R, et al. Detection of y-type subunit at the Glu-A1 locus in some Swedish bread wheat lines. J Cereal Sci. 1996; 23: 203-211. [CrossRef]
- Ravel C, Faye A, Ben-Sadoun S, Ranoux M, Dardevet M, Dupuits C, et al. SNP markers for early identification of high molecular weight glutenin subunits (HMW‑GSs) in bread wheat. Theor Appl Genet. 2020; 133: 751-770. [CrossRef]
- Roy N, Islam S, Al-Habbar Z, Yu Z, Liu H, Lafiandra D, et al. Contribution to breadmaking performance of two different HMW glutenin 1Ay alleles expressed in hexaploid wheat. J Agric Food Chem. 2020; 69: 36-44. [CrossRef]
- Juhasz A, Tamas L, Karsai I, Vida G, Lang L, Bedo Z. Identification, cloning and characterisation of a HMW-glutenin gene from an old Hungarian wheat variety, Bankuti 1201. Euphytica. 2001; 119: 75-79. [CrossRef]
- Caballero L, Martín LM, Alvarez JB. Relationships between the HMW- and LMW-glutenin subunits and SDS-sedimentation volume in Spanish hulled wheat lines. Czech J Genet Plant Breed. 2008; 44: 114-117. [CrossRef]
- Maryami Z, Huertas-García AB, Azimi MR, Hernández-Espinosa N, Payne T, Cervantes F, et al. Variability for glutenins, gluten quality, iron, zinc and phytic acid in a set of one hundred and fifty-eight common wheat landraces from Iran. Agronomy. 2020; 10: 1797. [CrossRef]
- Cao Y, Zhang J, Wang R, Sun H, Yan Y. Molecular characterization and SNP-based molecular marker development of two novel high molecular weight glutenin genes from Triticum spelta L. Int J Mol Sci. 2022; 23: 11104. [CrossRef]
- An X, Li Q, Yan Y, Xiao Y, Hsam SL, Zeller FJ. Genetic diversity of European spelt wheat (Triticum aestivum ssp. spelta L. em Thell.) revealed by glutenin subunit variations at the Glu-1 and Glu-3 loci. Euphytica. 2005; 146: 193-201. [CrossRef]
- Yasmeen F, Khurshid H, Ghafoor A. Genetic divergence for high-molecular weight glutenin subunits (HMW-GS) in indigenous landraces and commercial cultivars of bread wheat of Pakistan. Genet Mol Res. 2015; 14: 4829-4839. [CrossRef]
- Gobaa S, Kleijer G, Stamp P. 2··, a new high molecular weight glutenin subunit coded by Glu‐A1: Its predicted structure and its impact on bread‐making quality. Plant Breed. 2007; 126: 1-4. [CrossRef]
- Babay E, Hanana M, Mzid R, Slim-Amara H, Carrillo JM, Rodríguez-Quijano M. Influence of allelic prolamin variation and localities on durum wheat quality. J Cereal Sci. 2015; 63: 27-34. [CrossRef]
- Rodríguez-Quijano M, Vargas-Kostiuk ME, Ribeiro M, Callejo MJ. Triticum aestivum ssp. vulgare and ssp. spelta cultivars. 1. Functional evaluation. Eur Food Res Technol. 2019; 245: 1561-1570. [CrossRef]
- Galili G, Feldman M. Genetic control of endosperm proteins in wheat. 2. Variation in high-molecular-weight glutenin and gliadin subunits of Triticum aestivum. Theor Appl Genet. 1983; 66: 77-86. [CrossRef]
- Ayala M, Guzmán C, Peña RJ, Alvarez JB. Diversity of phenotypic plant and grain morphological and genotypic glutenin alleles in Glu-1 and Glu-3 loci traits of wheat landraces Triticum aestivum from Andalusia Southern Spain. Genet Resour Crop Evol. 2016; 63: 465-475. [CrossRef]
- Ribeiro M, Bancel E, Faye A, Dardevet M, Ravel C, Branlard G, et al. Proteogenomic characterization of novel x-type high molecular weight glutenin subunit 1Ax1.1. Int J Mol Sci. 2013; 14: 5650-5667. [CrossRef]
- Peng YC, Yu K, Zhang Y, Islam S, Sun D, Ma W. Two novel y-type high molecular weight glutenin genes in Chinese wheat landraces of the Yangtze-River region. PloS One. 2015; 1011: e0142348. [CrossRef]
- Gong F, Qi T, Zhang T, Lu Y, Liu J, Zhong X, et al. Comparison of the agronomic, cytological, grain protein characteristics, as well as transcriptomic profile of two wheat lines derived from wild emmer. Front Genet. 2022; 12: 804481. [CrossRef]
- Orlovskaya OA, Yatsevich KK, Vakula SI, Khotileva LV, Kilchevsky AV. Characterization of high molecular weight glutenin subunits in wild emmer wheat (Triticum dicoccoides). Cytol Genet. 2020; 54: 199-205. [CrossRef]
- Cao H, Duncan O, Islam S, Zhang J, Ma W, Millar AH. Increased wheat protein content via introgression of an HMW glutenin selectively reshapes the grain proteome. Mol Cell Proteom. 2021; 20: 100097. [CrossRef]
- Ma W, Zhang W, Gale KR. Multiplex-PCR typing of high molecular weight glutenin subunit alleles in wheat. Euphytica. 2003; 134: 51-60. [CrossRef]
- Liu SX, Chao SM, Anderson JA. New DNA markers for high molecular weight glutenin subunits in wheat. Theor Appl Genet. 2008; 118: 177-183. [CrossRef]
- De Bustos A, Rubio P, Jouve N. Molecular characterisation of the inactive allele of the gene Glu-A1 and the development of a set of AS-PCR markers for HMW glutenins of wheat. Theor Appl Genet. 2000; 100: 1085-1094. [CrossRef]
- Liu S, Rudd JC, Bai G, Haley SD, Ibrahim AM, Xue Q, et al. Molecular markers linked to important genes in hard winter wheat. Crop Sci. 2014; 54: 1304-1321. [CrossRef]
- Liang X, Zhen S, Han C, Wang C, Li X, Ma W, et al. Molecular characterization and marker development for hexaploid wheat-specific HMW glutenin subunit 1By18 gene. Mol Breed. 2015; 35: 221. [CrossRef]
- Dong Z, Yang Y, Zhang K, Li Y, Wang J, Wang Z, et al. Development of a new set of molecular markers for examining Glu-A1 variants in common wheat and ancestral species. PLoS One. 2017; 12: e0180766. [CrossRef]
- Giraldo P, Rodriguez-Quijano M, Simon C, Vazquez JF, Carrillo JM. Allelic variation in HMW glutenins in Spanish wheat landraces and their relationship with bread quality. Span J Agric Res. 2010; 8: 1012-1023. [CrossRef]
- Raciti CN, Doust MA, Lombardo GM, Boggini G, Pecetti L. Characterization of durum wheat Mediterranean germplasm for high and low molecular weight glutenin subunits in relation with quality. Eur J Agron. 2003; 19: 373-382. [CrossRef]
- Zhang Y, Schonhofen A, Zhang W, Hegarty J, Carter C, Vang T, et al. Contributions of individual and combined Glu-B1x and Glu-B1y high-molecular-weight glutenin subunits to semolina functionality and pasta quality. J Cereal Sci. 2020; 93:102943. [CrossRef]
- Amiour N, Bouguennec A, Marcoz C, Sourdille P, Bourgoin M, Khelifi D, et al. Diversity of seven glutenin and secalin loci within triticale cultivars grown in Europe. Euphytica. 2002b; 123: 295-305. [CrossRef]
- Goel S, Yadav M, Singh K, Jaat RS, Singh NK. Exploring diverse wheat germplasm for novel alleles in HMW-GS for bread quality improvement. J Food Sci Technol. 2018; 55: 3257-3262. [CrossRef]
- Sharma A, Garg S, Sheikh I, Vyas P, Dhaliwal HS. Effect of wheat grain protein composition on end-use quality. J Food Sci Technol. 2020; 57: 2771-2785. [CrossRef]
- Janni M, Cadonici S, Bonas U, Grasso A, Dahab AA, Visioli G, et al. Gene-ecology of durum wheat HMW glutenin reflects their diffusion from the center of origin. Sci Rep. 2018; 8: 16929. [CrossRef]
- McIntosh RA, Hart GE, Gale MD. Catalogue of gene symbols for wheat. Proceedings of the 8th International Wheat Genetics Symposium; 1993 July 20-25; Beijing, China. Beijing: Agricultural Scientech Press.
- Wang XF, Song RL, An Y, Pei H, Gao S, Sun DK, et al. Allelic variation and genetic diversity of HMW glutenin subunits in Chinese wheat (Triticum aestivum L.) landraces and commercial cultivars. Breed Sci. 2022; 72: 169-180. [CrossRef]
- Lawrence GJ. The high-molecular-weight glutenin subunit composition of Australian wheat cultivars. Aust J Agric Res. 1986; 37: 125-133. [CrossRef]
- Pattison A, Appelbee M, Trethowan RM. Characteristics of modern triticale quality: Glutenin and secalin subunit composition and mixograph properties. J Agric Food Chem. 2014; 62: 4924-4931. [CrossRef]
- Vallega V, Mello-Sampayo T. Variation in high-molecular-weight glutenin subunits amongst cultivars of Triticum turgidium L. from Portugal. Euphytica. 1987; 36: 755-762. [CrossRef]
- Roncallo PF, Guzmán C, Larsen AO, Achilli A, Dreisigacker S, Molfese E, et al. Allelic variation at glutenin loci (Glu-1, Glu-2 and Glu-3) in a worldwide durum wheat collection and its effect on quality attributes. Foods. 2021; 10: 2845. [CrossRef]
- Espí A, Giraldo P, Rodríguez-Quijano M, Carrillo JM. A PCR-based method for discriminating between high molecular weight glutenin subunits Bx7 and Bx7* in Triticum aestivum L. Plant Breed. 2012; 131: 571-573. [CrossRef]
- Pflüger LA, Martin LM, Alvarez JB. Variation in the HMW and LMW glutenin subunits from Spanish accessions of emmer wheat (Triticum turgidum ssp. dicoccum Schrank). Theor Appl Genet. 2001; 102: 767-772. [CrossRef]
- Henkrar F, El-Haddoury J, Iraqi D, Bendaou N, Udupa SM. Allelic variation at high-molecular weight and low-molecular weight glutenin subunit genes in Moroccan bread wheat and durum wheat cultivars. 3 Biotech. 2017; 7: 287. [CrossRef]
- Nucia A, Okoń S, Tomczyńska-Mleko M. Characterization of HMW glutenin subunits in European spring common wheat (Triticum aestivum L.). Genet Resour Crop Evol. 2019; 66: 579-588. [CrossRef]
- Butow BJ, Gale KR, Ikea J, Juhasz A, Bedo Z, Tamas L, et al. Dissemination of the highly expressed Bx7 glutenin subunit (Glu-B1al allele) in wheat as revealed by novel PCR markers and RP-HPLC. Theor Appl Genet. 2004; 109: 1525-1535. [CrossRef]
- Ragupathy R, Naeem H, Reimer E, Lukow O, Sapirstein H, Cloutier S. Evolutionary origin of the segmental duplication encompassing the wheat Glu-B1 locus encoding the overexpressed Bx7 (Bx7OE) high molecular weight glutenin subunit. Theor Appl Genet. 2008; 116: 283-296. [CrossRef]
- Li J, Han C, Zhen S, Li X, Yan Y. Characterization of HMW glutenin subunit Bx7OE and its distribution in common wheat and related species. Plant Genet Resour. 2014; 12: 191-198. [CrossRef]
- Pourmohammadi K, Abedi E, Hashemi SM. Gliadin and glutenin genomes and their effects on the technological aspect of wheat-based products. Curr Res Food Sci. 2023; 7: 100622. [CrossRef]
- Vallega V. Comparative analysis of high-molecular-weight glutenin subunit composition in various Triticum species. Plant Breed. 1988; 100: 241-246. [CrossRef]
- McIntosh RA, Hart GE, Gale MD. Catalogue of gene symbols for wheat: 1989 supplement. Ann Wheat Newsl. 1989; 35: 231-241.
- Vallega V. High-molecular-weight glutenin subunit composition of Italian Triticum durum cultivars and spaghetti cooking quality. Cereal Res Commun. 1986; 14: 251-257.
- Lawrence GJ, Macritchie F, Wrigley CW. Dough and baking quality of wheat lines deficient in glutenin subunits controlled by the Glu-A1, Glu-B1 and Glu-D1 loci. J Cereal Sci. 1988; 7: 109-112. [CrossRef]
- Kolster P, Kretching CF, van Gelder WMJ. Variation in high molecular weight glutenin subunits of Triticum aestivum and T. turgidum ssp. dicoccoides. Euphytica. 1988; 39: 141-145. [CrossRef]
- Dai S, Xu D, Yan Y, Wen Z, Zhang J, Chen H, et al. Characterization of high- and low-molecular-weight glutenin subunits from Chinese Xinjiang wheat landraces and historical varieties. J Food Sci Technol. 2020; 57: 3823-3835. [CrossRef]
- Marchylo BA, Lukow OM, Kruger JE. Quantitative variation in high molecular weight glutenin subunit 7 in some Canadian wheats. J Cereal Sci. 1992; 15: 29-37. [CrossRef]
- Liu L, Wang A, Appels R, Ma J, Xia X, Lan P, et al. A MALDI-TOF based analysis of high molecular weight glutenin subunits for wheat breeding. J Cereal Sci. 2009; 50: 295-301. [CrossRef]
- Rodriguez-Quijano M, Vasquez JF, Carrillo JM. Variation of high-molecular-weight glutenin subunits in Spanish landraces of Triticum aestivum ssp. vulgare and ssp. spelta. J Genet Breed. 1990; 44: 121-126.
- Hernández-Espinosa N, Payne T, Huerta-Espino J, Cervantes F, Gonzalez-Santoyo H, Ammar K, et al. Preliminary characterization for grain quality traits and high and low molecular weight glutenins subunits composition of durum wheat landraces from Iran and Mexico. J Cereal Sci. 2019; 88: 47-56. [CrossRef]
- Morgunov AI, Rogers WJ, Sayers EJ, Metakovsky EV. The high-molecular-weight glutenin subunit composition of Soviet varieties. Euphytica. 1990; 51: 41-52. [CrossRef]
- Moragues M, Zarco-Hernández J, Moralejo MA, Royo C. Genetic diversity of glutenin protein subunits composition in durum wheat landraces [Triticum turgidum ssp. turgidum convar. durum (Desf.) MacKey] from the Mediterranean basin. Genet Resour Crop Evol. 2006; 53: 993-1002. [CrossRef]
- Daskalova N, Doneva, Spetsov P. Characterization of Triticale (× Triticosecale Wittmack) accessions and reciprocal hybrids possessing wheat 1D chromosome. Agric Conspec Sci. 2021; 86: 107-115.
- Lei ZS, Gale KR, He ZH, Gianibelli C, Larroque O, Xia XC, et al. Y-type gene specific markers for enhanced discrimination of high-molecular weight glutenin alleles at the Glu-B1 locus in hexaploid wheat. J Cereal Sci. 2006; 43: 94-101. [CrossRef]
- Jin M, Xie ZZ, Ge P, Li J, Jiang SS, Subburaj S, et al. Identification and molecular characterisation of HMW glutenin subunit 1By16* in wild emmer. J Appl Genet. 2012; 53: 249-258. [CrossRef]
- Chegdali Y, Ouabbou H, Essamadi A, Cervantes F, Ibba MI, Guzmán C. Assessment of the glutenin subunits diversity in a durum wheat (T. turgidum ssp. durum) collection from Morocco. Agronomy. 2020; 10: 957. [CrossRef]
- Zhao HB, Gao CJ, Song WF, Zhang YB, Gao DD, Zhang XM, et al. Quality differences between NILs of wheat variety Longmai 20 possessing HMW-GS 7OE + 8* and 17 + 18. Cereal Res Commun. 2020; 48: 493-498. [CrossRef]
- Caballero L, Martin LM, Alvarez JB. Allelic variation of the HMW glutenin subunits in Spanish accessions of spelt wheat (Triticum aestivum ssp. spelta L. em. Thell.). Theor Appl Genet. 2001; 103: 124-128. [CrossRef]
- Ruiz M, Carrillo JM. Relationships between different prolamin proteins and some quality properties in durum wheat. Plant Breed. 1995; 114: 40-44. [CrossRef]
- Xu SS, Khan K, Klindworth DL, Faris JD, Nygard G. Chromosome location of genes from novel glutenin subunits and gliadins in wild emmer (Triticum turgidum var. dicoccoides). Theor Appl Genet. 2004; 108: 1221-1228. [CrossRef]
- Shao H, Liu Th, Ran CF, Li LQ, Yu J, Gao X, et al. Isolation and molecular characterization of two novel HMW-GS genes from Chinese wheat (Triticum aestivum L.) landrace Banjiemang. Genes Genomics. 2015; 37: 45-53. [CrossRef]
- Tohver M, Kann A, Täht R, Mihhalevski A, Hakman J. Quality of triticale cultivars suitable for growing and bread-making in northern conditions. Food Chem. 2005; 89: 125-132. [CrossRef]
- Fang J, Liu Y, Luo J, Wang Y, Shewry PR, He G. Allelic variation and genetic diversity of high molecular weight glutenin subunit in Chinese endemic wheats (Triticum aestivum L.). Euphytica. 2009; 166: 177-182. [CrossRef]
- Gao X, Appelbee MJ, Mekuria GT, Chalmers KJ, Mather DE. A second ‘overexpression’ allele at the Glu-B1 high-molecular-weight glutenin locus of wheat: Sequence characterisation and functional effects. Theor Appl Genet. 2012; 124: 333-343. [CrossRef]
- Carmona S, Alvarez JB, Caballero L. Genetic diversity for morphological traits and seed storage proteins in Spanish rivet wheat. Biol Plant. 2010; 54: 69-75. [CrossRef]
- Caballero L, Peña RJ, Martín LM, Alvarez JB. Characterization of Mexican Creole wheat landraces in relation to morphological characteristics and HMW glutenin subunit composition. Genet Resour Crop Evol. 2010; 57: 657-665. [CrossRef]
- Jang YR, Kim S, Sim JR, Lee SB, Lim SH, Kang CS, et al. High-throughput analysis of high-molecular weight glutenin subunits in 665 wheat genotypes using an optimized MALDI-TOF-MS method. 3 Biotech. 2021; 11: 92. [CrossRef]
- McIntosh RA, Dubcovsky J, Rogers WJ, Xia XC, Raupp WJ. Catalogue of gene symbols for wheat: 2020 Supplement. Ann Wheat Newsl. 2020; 66: 109-128.
- Alvarez JB, Guzmán C. Recovery of wheat heritage for traditional food: Genetic variation for high molecular weight glutenin subunits in neglected/underutilized wheat. Agronomy. 2019; 9: 755. [CrossRef]
- Chen J, Zhuo GY, Yu L, Zhang AM, Sun J, Yang W, et al. Establishment of multiplex PCR system for high molecular weight glutenin subunits in wheat. Mol Plant Breed. 2008; 6: 363-369.
- Gianibelli MC, Gupta RB, Lafiandra D, Margiotta B, MacRitchie F. Polymorphism of high Mr glutenin subunits in Triticum tauschii: Characterization by chromatography and electrophoretic methods. J Cereal Sci. 2001; 33: 39-52. [CrossRef]
- Lukow OM, Forsyth SA, Payne PI. Over-production of HMW glutenin subunits coded on chromosome 1B in common wheat, Triticum aestivum. J Genet Breed. 1992; 46: 187-192.
- Bellil I, Hamdi O, Khelifi D. Diversity of five glutenin loci within durum wheat (Triticum turgidum L. ssp. durum (Desf.) Husn.) germplasm grown in Algeria. Plant Breed. 2014; 133: 179-183. [CrossRef]
- Mir Ali N, Arabi MIE, Al-Safadi B. Frequencies of high and low molecular weight glutenin subunits in durum wheat grown in Syria. Cereal Res Commun. 1999; 27: 301-305. [CrossRef]
- Dai S, Yan ZH, Wei YM, Zheng YL. Allelic variations of high molecular weight glutenin subunits HMW-GS in Tibetan wheat. Acta Agric Boreali Occident Sin. 2004; 2: 90-93.
- Yan Z, Dai S, Liu D, Wei Y, Wang J, Zheng Y. Isolation and characterization of a novel Glu-Bx HMW-GS allele from Tibet bread wheat landrace. Int J Agric Res. 2009; 4: 38-45. [CrossRef]
- Hlozáková TK, Gálová Z, Šliková S, Leišová-Svobodová L, Beinhauer J, Dyčka F, et al. Molecular characterization of novel x-type HMW glutenin subunit 1B×6.5 in wheat. Plants. 2021; 10: 2108. [CrossRef]
- Guo X, Li H, Xiang J, Xu X, Liu W, Gao A, et al. Genetic variation of high molecular weight glutenin subunits in wheat accessions in China. Crop Sci. 2011; 51: 2423-2429. [CrossRef]
- Bietz JA, Shepherd KW, Wall JS. Single-kernel analysis of gluten: Use in wheat genetics and breeding. Cereal Chem. 1975; 52: 513-532.
- Jang YR, Cho K, Kim SW, Altenbach SB, Lim SH, Sim JR, et al. Development of an optimized MALDI-TOF-MS method for high-throughput identification of high-molecular-weight glutenin subunits in wheat. Molecules. 2020; 25: 4347. [CrossRef]
- Tikhonova M, Ingver A, Koppe R. Identification of Glu-A1 and Glu-D1 high molecular weight glutenin subunits of common wheat (Triticum aestivum L.) using genetic markers. Proc Latv Acad Sci Sect B. 2018; 72: 349-357. doi: 10.2478/prolas-2018-0047. [CrossRef]
- Shin D, Cha JK, Lee SM, Ko JM, Lee JH. Validation and selection of functional allele-specific molecular markers to analyze High-Molecular-Weight glutenin subunit composition in wheat. Korean J Breed Sci. 2020; 52: 235-243. [CrossRef]
- Shin D, Cha JK, Lee SM, Kabange NR, Lee JH. Rapid and easy high-molecular-weight glutenin subunit identification system by lab-on-a-chip in wheat (Triticum aestivum L.). Plants. 2020; 9: 1517. [CrossRef]
- Terasawa Y, Kawahara T, Sasakuma T, Sasanuma T. Evaluation of the genetic diversity of an Afghan wheat collection based on morphological variation, HMW glutenin subunit polymorphisms, and AFLP. Breed Sci. 2009; 59: 361-371. [CrossRef]
- Niwa K, Suzuki H, Tominaga T, Nasim S, Anwar R, Ogawa M, et al. Evaluation of genetic variation in high molecular weight glutenin subunits of seed storage protein using landraces of common wheat from Pakistan. Cereal Res Commun. 2008; 36: 327-332. [CrossRef]
- Lagudah ES, Halloran GM. Phylogenetic relationships of Triticum taushii, the D genome donor of hexaploid wheat 1. Variation in HMW subunits of glutenin and gliadins. Theor Appl Genet. 1988; 75: 592-598. [CrossRef]
- Rogers WJ, Payne PI, Seekings JA, Sayers EJ. Effect on bread-making quality of x-type and y-type subunits of glutenin. J Cereal Sci. 1991; 14: 209-221. [CrossRef]
- Buonocore F, Hickman DR, Caporale C, Porceddu E, Lafiandra D, Tatham AS, et al. Characterisation of a novel high Mr glutenin subunit encoded by chromosome 1D of bread wheat. J Cereal Sci. 1996; 23: 55-60. [CrossRef]
- Alvarez JB. Spanish spelt wheat: From an endangered genetic resource to a trendy crop. Plants. 2021; 10: 2748. [CrossRef]
- Cong H, Takata K, Ikeda T, Yanaka M, Fujimaki H, Nagamine T. Characterization of a novel high-molecular-weight glutenin subunit pair 2.6 + 12 in common wheat landraces in the Xinjiang Uygur autonomous district of China. Breed Sci. 2007; 57: 253-255. [CrossRef]
- Guo X, Guo J, Li X, Yang X, Li L. Molecular characterization of two novel Glu-D1-encoded subunits from Chinese wheat (Triticum aestivum L.) landrace and functional properties of flours possessing the two novel subunits. Genet Resour Crop Evol. 2010; 57: 1217-1225. [CrossRef]
- Mihálik D, Gregová E, Galuszka P, Ohnoutková L, Klempová T, Ondreičková K, et al. Characterisation of a novel high-molecular-weight glutenin subunit 1Dy12.3 from hexaploid wheat (Triticum aestivum L.). Czech J Genet Plant Breed. 2012; 48: 157-168. [CrossRef]
- Zheng W, Peng YC, Ma JH, Appels R, Sun DF, Ma WJ. High frequency of abnormal high molecular weight glutenin alleles in Chinese wheat landraces of the Yangtze-River region. J Cereal Sci. 2011; 54: 401-408. [CrossRef]
- Jiang Q, Wei Y, Wang J, Yan Z, Zheng Y. Isolation and sequence analysis of HMW glutenin subunit 1Dy10.1 ecoding gene from Xinjiang wheat (Triticum petropavlovskyi Udacz. et Migusch). Agric Sci in China. 2006; 5: 81-89. [CrossRef]
- Yan Y, Hsam SL, Yu J, Jiang Y, Zeller FJ. Allelic variation of the HMW glutenin subunits in Aegilops tauschii accessions detected by sodium dodecyl sulphate (SDS-PAGE), acid polyacrylamide gel (A-PAGE) and capillary electrophoresis. Euphytica. 2003; 130: 377-385. [CrossRef]
- Jang YR, Beom HR, Altenbach SB, Lee MK, Lim SH, Lee JY. Improved method for reliable HMW-GS identification by RP-HPLC and SDS-PAGE in common wheat cultivars. Molecules. 2017; 22: 1055. [CrossRef]
- Ishikawa G, Nakamura T. A new co-dominant PCR-based marker to identify the high-molecular-weight glutenin subunit combination “5 + 10” of common wheat. Wheat Inf Serv. 2007; 103: 1-3.
- Dai S, Zhai Z, Yang W, Liu Q, Jiang J, Li J, et al. Quality of wheat lines solely expressing high-molecular-weight glutenin allelic variation of 1Dy 12. N Z J Crop Hortic Sci. 2023; 51: 93-107. [CrossRef]
- Wang Y, Guo ZR, Chen Q, Li Y, Zhao K, Wan YF, et al. Effect of high-molecular-weight glutenin subunit Dy10 on wheat dough properties and end-use quality. J Integr Agric. 2023; 22: 1609-1617. [CrossRef]