小麦谷蛋白聚合体的MS-SDS-PAGE及其与面包烘烤品质的关系

选用品质(微量SDS沉淀值、稳定时间)优劣不同的10个"9311168///81831-1/pernell//京411"的F6品系, 探索多层浓缩胶SDS-PAGE(MS-SDS-PAGE)的实验方法, 初步探讨可溶性谷蛋白的分子量分布状况和不溶性谷蛋白(GMP)与面包烘烤品质的关系. 结果表明, 通过SDS-磷酸缓冲液可将谷蛋白聚合体分成两部分: 分子量较小的SDS-可溶性谷蛋白     

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

To 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.     

Survey and new insights in the application of PCR‐based molecular markers for identification of HMW‐GS at the Glu‐B1 locus in durum and bread wheat

Wheat, among all cereal grains, possesses unique characteristics conferred by gluten; in particular, high molecular weight glutenin subunits (HMW‐GS) are of considerable interest as they strictly relate to bread‐making quality and contribute to strengthening and stabilizing dough. Thus, the identification of allelic composition, in particular at the Glu‐B1 locus, is very important to wheat quality improvement. Several PCR‐based molecular markers to tag‐specific HMW glutenin genes encoding Bx and By subunits have been developed in recent years. This study provides a survey of the molecular markers developed for the HMW‐GS at the Glu‐B1 locus. In addition, a selection of molecular markers was tested on 31 durum and bread wheat cultivars containing the By8, By16, By9, Bx17, Bx6, Bx14 and Bx17 Glu‐B1 alleles, and a new assignation was defined for the ZSBy9_aF1/R3 molecular marker that was specific for the By20 allele. We believe the results constitute a practical guide for results that might be achieved by these molecular markers on populations and cultivars with high variability at the Glu‐B1 locus.     

Introduction of high molecular weight glutenin subunits 5 + 10 for the improvement of the bread-making quality of hexaploid triticale

In an earlier study, chromosome 1D of the hexaploid breadwheat cultivar ‘Chinese Spring’ was introduced into hexaploid triticale to improve its bread‐making quality. That specific chromosome, 1D, carried the a allele at the Glu‐D1 locus coding for high molecular weight (HMW) glutenin subunits 2 + 12, and since subunits 2 + 12 are associated with poor bread‐making quality in wheat, in the present study hexaploid 1D substitution triticale was crossed with octoploid triticale with the d allele at the Glu‐D1 locus encoding HMW glutenin subunits 5 + 10. Following backcrosses to different triticale varieties, 1D substitution lines were established that had Glu‐D1 allele a or d in an otherwise genetically similar background, and the influence of these two different alleles on bread‐making quality of hexaploid triticale was compared. The agronomic performance of 76 selected lines was evaluated in a field trial. The Zeleny sedimentation value was determined as a parameter for bread‐making quality, and related to the presence of chromosome 1D, the different glutenin alleles and the nature of the substitution. The presence of chromosome 1D had a significant and positive effect on the Zeleny sedimentation value, but the difference between the two glutenin alleles 2 + 12 and 5 + 10 was not as obvious as in wheat. Owing to its high cytological stability and minimal effect on agronomic performance, substitution 1D(1A) appears to be the most desirable one to use in triticale breeding.     

Effect of Shading from Jointing to Maturity on High Molecular Weight Glutenin Subunit Accumulation and Glutenin Macropolymer Concentration in Grain of Winter Wheat

Accumulations of high molecular weight glutenin subunits (HMW‐GS) and glutenin macropolymer (GMP) in wheat grains are important indicators of grain quality. Two wheat cultivars, Yangmai 158 (shading tolerant) and Yangmai 11 (shading intolerant) which contains the same subunit pairs of 7 + 8 and 2 + 12, were used to evaluate the impacts of shading on HMW‐GS accumulation and GMP concentration in the grain. Three shading levels were implemented from jointing to maturity, i.e. S1, S2 and S3, in which the plants received 8 %, 15 % and 23 % less radiation of the control (S0), respectively. The initial formation of HMW‐GS was pre‐dated by shading. The rapid HMW‐GS accumulation duration was shortened, and the accumulation rate during late grain filling period was lowered in the two relatively severe shaded treatments (S2 & S3). Thus, the total HMW‐GS accumulation in single grain at maturity was lower in S2 and S3 than in the control (S0). However, concentrations of HMW‐GS and GMP at maturity increased because of the reduced single grain weight in S2 and S3, as compared to S0. In contrast, the low density shading (S1) prolonged the rapid accumulation duration of HMW‐GS, hence increased the accumulation and concentration of HMW‐GS in the grains. Consequently, S1 reduced falling number and SDS‐sedimentation volume, while shortened dough development time (DDT) and dough stability time (DST). In contrast, S2 and S3 increased falling number, wet‐gluten concentration and SDS‐sedimentation volume, and lengthened the DDT and DST. In addition, the fluctuations in accumulations of HMW‐GS and GMP and most quality traits because of shading in Yangmai 158 were less than Yangmai 11. The interrelations between HMW‐GS accumulation, GMP concentration and quality of grain and dough were further discussed.     

Characterization of high-molecular-weight glutenin subunit genes from Elytrigia elongata

Three high‐molecular‐weight glutenin subunit (HMW‐GS) genes from Elytrigia elongata (Host) Nevski were characterized by determining the coding sequences of two x‐type subunit genes Ee2.1 and Ee1.9, and one y‐type subunit gene Ee1.8 with 2082, 1938 and 1788 bp, respectively. The numbers of amino acids in the central repeat domains of Ee2.1, Ee1.9 and Ee1.8 were considerably fewer than the other known HMW‐GSs with substitutions, insertions and/or deletions involving a single or more amino acid residues. Moreover, an extra cysteine (Cys) was found in the repeated domain of x‐type subunit Ee2.1. The difference in the number and position of Cys residues might be associated with the good dough quality. The extra Cys in the good‐quality subunit Dx5 was at the beginning of the repetitive domain, while the extra Cys in Ee2.1 was at the central repetitive domain. Evolutionary relationships between the HMW‐GSs from E. elongata and the known HMW‐GSs were estimated. It transpired that Ee1.9, Ee2.1 and Bx7 were clustered into one subgroup with high bootstrap values, while Ee1.8 was closely related to Ay.     

不同品质类型春小麦HWM—GS形成时间和积累强度及与品质的关系

供试材料籽粒形成过程中，麦谷蛋白低分子量亚基部分首先出现，随籽粒发育，麦谷蛋白亚基类型逐渐增多，HMW－GS各个亚基在开花后10天内没有形成，开花15天左右，出现Glu-1位点上编码的高分子量X亚基，25天时，所具有的HMW－GS全部形成，随灌浆成熟，HMW－GS各亚基积累呈递增趋势，积累高峰出现在开花20天至成熟，5＋10亚基与具有该亚基供试品种的优良品质之间存在密切关系，但具有2＋12亚基的东农7742的亚基形成早，2与12亚基的高积累量及1和7＋8亚基的高积累使其同样具有优质特性，Glu-1品质评分与沉淀值之间呈显著正相关，能够反映小麦品质，但并不绝对，小麦高分子量麦谷蛋白亚基总积累与沉淀值呈显著正相关，各高分子量亚基与沉淀值之间的相关未达显著水平，但亚基2与12的积累量与沉淀值的相关性强，尤其是12亚基的积累。     

不同品质类型春小麦HMW-GS形成时间和积累强度及与品质的关系

供试材料籽粒形成过程中, 麦谷蛋白低分子量亚基部分首先出现. 随籽粒发育, 麦谷蛋白亚基类型逐渐增多. HMW-GS各个亚基在开花后10天内没有形成, 开花15天左右, 出现Glu-1位点上编码的高分子量X型亚基. 25天时, 所具有的HMW-GS全部形成. 随灌浆成熟, HMW-GS各亚基积累呈递增趋势, 积累高峰出现在开花20天至成熟. 5+10亚基与具     

High molecular weight glutenin subunit composition of Chinese bread wheats

Summary The endosperm storage proteins of 205 Chinese bread wheat cultivars and advanced lines were fractionated by SDS-PAGE to determine their high molecular weight (HMW) glutenin subunit composition. Seventeen alleles were identified: three at Glu-A1, eight at Glu-B1, and six at Glu-D1. The most common alleles were Null, 1, 7+8, 7+9, and 2+12. The results indicate that wheats from different regions differ in their frequencies of HMW glutenin subunits, however, none of the subunits could be related to specific environments. The glutenin quality scores of Chinese wheats ranged from 3 to 10, with an average of 6.7. Increasing quality scores have implications in improving steam-bread making quality for Chinese consumers. On the basis of HMW glutenin subunit composition, Chinese wheats are close to European wheats, especially Italian wheats because several Italian introductions are widely distributed in the pedigrees of Chinese wheat.     

小麦新品种“川农16”低分子量谷蛋白亚基新基因的分子克隆

采用PCR方法从小麦（Triticum aestivum L.）新品种“川农16”中克隆得到一个低分子量谷蛋白亚基（LMW-GS）新基因LMWCN16-2（GenBank No.AY296753）。该基因具有LMW-GS基因的典型结构特征，编码区全长906 bp，编码301个氨基酸。推导氨基酸序列比较显示，LMWCN16-2与已报道的LMW-GS基因，尤其是Glu-A3位点编码的基因序列有很     

低分子量谷蛋白亚基GlU-A3和GlU-B3位点对小麦面筋强度和烘焙特性影响

低分子量谷蛋白亚基是小麦谷蛋白亚基的重要组成部分,黄淮麦区小麦低分子量谷蛋白亚基组成对品质的效应尚缺乏系统的研究。本研究采用SDS-PAGE方法,鉴定了黄淮麦区42个小麦品种的Glu-A3位点和Glu-B3位点低分子量谷蛋白亚基组成,分析了低分子量谷蛋白亚基对小麦面筋强度和烘烤品质的影响。结果表明,在Glu-A3位点,对面筋强度和面包烘焙品质正向效应为:d,b>a,e;在Glu-B3位点,对面筋强度正效应为:h,d>f>g,b,j,对面包烘焙品质正向效应为:h>f,d>g,b,j。Glu-A3d/Glu-B3h亚基组合具有较好的面筋强度和烘焙品质。就低分子量谷蛋白亚基单个变异位点对品质综合效应而言,Glu-B3位点对品质作用比较大,与Glu-B1位点相近,同时,高低分子量谷蛋白亚基之间存在着互作效应,以Glu-B1/Glu-A3和Glu-D1/Glu-B3位点的互作效应比较显著。Glu-A3和Glu-B3位点及其所编码的不同亚基种类对品质的效应差异显著,并且与高分子量谷蛋白亚基位点存在互作,对不同位点优质亚基的聚合将有助于小麦品质的遗传改良。     

The high and low molecular weight glutenin subunit polymorphism of Algerian durum wheat landraces and old cultivars

The high molecular weight (HMW) and B‐zone low molecular weight (B‐LMW) glutenin subunit composition of 45 Algerian durum wheat (Triticum turgidum L. var. durum) landraces and old cultivars were examined by sodium‐dodecyl‐sulphate polyacrylamide gel electrophoresis (SDS‐PAGE). Nine accessions were heterogeneous and presented two or three genotypes. All together, 33 glutenin patterns were detected, including 12 for HMW and 15 for B‐LMW glutenin subunits. Twenty‐four different alleles were identified for the five glutenin loci studied, Glu‐A1 (3), Glu‐B1 (6), Glu‐A3 (8), Glu‐B3 (5) and Glu‐B2 (2). Five new alleles were found, three at Glu‐A3 and two at Glu‐B3. At the Glu‐1 loci, the Glu‐A1c‐Glu‐B1e allelic composition was predominant (31%). For the B‐LMW glutenins, the most common allelic composition was Glu‐A3a‐Glu‐B3a‐Glu‐B2a (36%). The collection analysed shows a high percentage of glutenin alleles and allele combinations related to high gluten strength, together with some others that have not been tested so far. This information could be useful to select local varieties with improved quality and also as a source of genes to develop new lines when breeding for quality.     

高分子量麦谷蛋白亚基组成与小麦烘烤品质关系研究

用SDS-PAGE方法测定了全国9个小麦主产省、市163个小麦品种和11个引进品种的高分子量麦谷蛋白亚基（HMW-GS）组成及其含量、沉降值和面粉GMP含量。结果表明，不同HMW-GS及其组合形式对小麦品质的影响显著不同，某些HMW-GS对我国小麦烘烤品质的影响不同于其他国家，如4+12亚基影响较大，而7+8亚基影响偏小。但单个亚基品质评分     

对小麦不同HMW麦谷蛋白亚基质量评分系统的评价

小麦HMW麦谷蛋白亚基组成不同是造成各品种间烘烤品质差异的主要原因。不同研究者分别依据亚基间沉淀值（Payne等，1987）、评价值（傅宾孝等．1989）、抗延伸力（赵友梅等，1990）以及包括沉淀值在内的多个性状（赵和等，1994）的差异。先后建立了各自的评分系统。比较研究结果表明，前3种亚基评分系统对亚基的质量评分具有一定的共性，个别亚基的评分则存在差异；赵和等（1994）的评分系统则侧重考虑1D控制的亚基对烘烤品质的决定性作用，1A和1B控制的亚基作用甚小，因而与其余3种评分方法存在较大分歧。相关分析结果表明，就评价中国小麦品种的品质而言，国内制订的评分系统优于国外的。除容重、灰分等性状外，HMW麦谷蛋白亚基组成与大多数品质性状呈显著或极显著相关关系．     

Relationship between common wheat (Triticum aestivum L.) gluten proteins and dough rheological properties

This paper reports the correlation between the rheological properties of bread wheat dough and the types and quantities of endosperm proteins in 28 common wheat cultivars. Different methods were used to analyse the allelic composition of these cultivars and the relative quantities of the different proteins contributing to the gluten structure. Neither dough strength (W) nor tenacity/extensibility (P/L) correlated with allelic composition. Different wheats with the same allelic composition (i.e., with respect to glutenins) showed different rheological properties. The glutenins were the most influential components of W and P/L, especially the high molecular weight (HMW) glutenin subunits and in particular the type x form. These proteins seem to increase W and are the main constituents of the gluten network. The gliadins and low molecular weight (LMW) glutenin subunits appear to act as a “solvent”, and thus modify the rheological properties of the dough by either interfering with the polymerisation of the HMW glutenin subunits, or by altering the relative amounts of the different types of glutenin available. Thus, the protein subunits coded for by the alleles Glu-B1x7 and Glu-D1x5 stabilised the gluten network, whereas those coded for by Glu-B1x17 and Glu-D1x2 had the opposite effect. Dough properties therefore appear to depend on the glutenin/gliadins balance, and on the ratio of the type x and type y HMW proteins. The influence of external factors seems to depend on the allelic composition of each cultivar.     

应用灰色关联分析法综合评估小麦高分子量麦谷蛋白亚基的研究

本文利用在河南种植的72个小麦品种面包烘烤品质指标的试验资料,借助于灰色关联分析法,对11种高分子量麦谷蛋白亚基进行了综合评估.结果表明:等权关联度与加权关联度分析结果基本吻合;Glu-1D5+10亚基对小麦烘烤品质的贡献最大;各亚基的关联度排序与其实际烘焙功能相一致.同时认为,采用多个品质指标的综合评估结果制定HMW麦谷蛋白亚基的评分系统,可能比用单一指标制定的评分方法更可靠.     

Influence of high molecular weight glutenin subunit substitution on rheological behaviour and bread-baking quality of near-isogenic lines developed from Chinese wheats

Three near‐isogenic lines (NILs) of wheat involving Glu‐B1 and Glu‐D1 alleles were used to study the genetic contribution of high molecular weight glutenin subunits (HMW‐GS) to gluten strength. The HMW‐GS composition of each NILs was determined by SDS‐PAGE. No significant differences were found in grain protein contents among the NILs. Gluten strength and dough‐mixing properties were measured by the Farinograph, the Extensograph, and SDS‐sedimentation (SDS‐SE). Results indicated that line 2, containing the Glu‐1B 14 + 15 and Glu‐1D 5 + 10 combination of subunits, had higher values for flour quality, dough rheological parameters, and bread‐baking quality when compared with lines 8 and 13. Line 8, containing Glu‐1B 7 + 9 and Glu‐1D 5 + 10, was better than line 13 with the Glu‐1B 14 + 15 and Glu‐1D 10 combination. Some major parameters appeared significantly different. The presence of Glu‐1B 14 + 15 was associated with higher dough strength based on SDS‐SE volume and several rheological parameters when compared with Glu‐1B 7 + 9. Lines with subunit 10 at Glu‐D1 performed significantly worse than those with 5 + 10 in gluten index, SDS‐SE volume, Farinograph stability time, Extensograph area and bread‐baking quality.     

PCR-based assay for detecting IB-genes for low molecular weight glutenin subunits related to gluten quality properties in durum wheat

A PCR assay has been developed for selecting low molecular weight (LMW) glutenin genes, located on chromosome 1B, and related to durum wheat quality characteristics. Most durum wheat lines possessing good technological properties can be identified on the basis of the presence of specific 1B LMW glutenin components that have been designated LMW-2 glutenin subunits. On the basis of nucleotide sequences corresponding to LMW glutenin genes, a series of specific oligonucleotide primers were prepared and used in PCR analysis. A pair of these primers gave a single amplification product which can distinguish between durum wheat lines possessing LMW-2 glutenin subunits and lines possessing other 1B-LMW allelic variants. Because the proposed PCR analysis can be carried out using part of the endosperm of a single seed, it represents a helpful approach for speeding up the selection of genotypes possessing LMW-2 glutenin subunits. This part of primers could also be very useful in genome mapping analysis and for testing the purity of wheat flour stock.     

Relationships between different prolamin proteins and some quality properties in durum wheat

The objective of this paper was to study the differences between some prolamin variants coded at the loci Glu-3/Gli-1, Glu-1 and Gli-A2 and their relative roles in durum-wheat quality. F₃ lines from four durum wheat crosses (‘Abadia’בMexicali’. ‘Oscar’בArdente’, ‘Oscar × Mexicali’ and ‘Alaga’בC. of Balazote’) were analysed for gliadin and glutenin composition by electrophoresis. Whole-grain-derived samples were analysed for SDS sedimentation (SDSS) value, mixing properties, and contents of protein and vitreousness. The glutenin patterns LMW-2. LMW-2^? and LMW-2 (CB) at Glu-B3/Gli-B1 were associated with better gluten quality than were LMW-1 and LMW-2*. The glutenin subunits LMW4 and LMW3 + 15 at Glu-A3/Gli-A1 and HMW-1 showed better mixing properties than LMW7 + 12, LMW5 and the null phenotype. respectively. The HMW glutenin subunits 20 + 8 at Glu-B1 showed a negative association with gluten quality, but the rest of the HMW glutenin subunits and α-gliadins did not show any influence on gluten quality. Correlations between the results of the SDSS test and the mixograph were highly significant, but no correlation was found between these results and protein and vitreousness contents. The results are discussed in relation to the development of durum wheat varieties with improved qualities.     

Glu-1位点缺失对小麦麦谷蛋白聚合体粒度分布及面团特性的影响

以Glu-1位点正常和部分缺失的小麦品系为材料,探讨HMW-GS和LMW-GS组成与谷蛋白聚合体粒度分布和面团特性的关系,为利用HMW-GS缺失系改良小麦品质提供理论依据。在20个供试硬白冬麦品系中,1个品系为Glu-A1位点缺失,5个品系为Glu-D1缺失,3个品系为Glu-A1和Glu-D1双缺失。所有品系的蛋白质含量皆较高(13.39%~14.12%),品系间无显著差异,缺失系与非缺失系间也无显著差异。Glu-1位点缺失显著降低了高分子量谷蛋白/低分子量谷蛋白比(HMW/LMW)、不溶性谷蛋白大聚体的含量和百分比。谷蛋白/醇溶蛋白比(GLU/GLI)在基因型间变幅较小,且在缺失系和非缺失系间无显著差异。Glu-1位点缺失显著降低了面团弹性,但显著提高了面团的延展性。部分Glu-1位点缺失系仍具有较高的面团强度和突出的延展性,谷蛋白聚合体粒度分布和面团特性受谷蛋白亚基组成和表达量的共同影响。研究结果表明,利用Glu-1位点亚基缺失可能是改善面筋延展性,提高食品加工品质的方法之一。