150个小麦品种高分子量谷蛋白亚基组成与蛋白质含量和沉降值关系的研究

对150个不同小麦品种高分子量麦谷蛋白亚基与蛋白质含量、沉降值之间的关系进行了研究,结果表明:Glu-1三位点控制的亚基等位变异与品质性状关系密切.A1位点亚基出现频率高于N,对品质效应以1>N;B1位点7+9亚基对出现频率最高,其次为7+8,各亚基对蛋白质含量效应以8>17+18>7+8>13+19>7+9>14+15,对沉降值效应以8>13+19>7+8>7+9>14+15>7>17+18;D1位点2+12亚基对频率高于5+10,各亚基对品质效应以5+10>5+12>2+12.具有亚基1,8或7+8,5+10组合类型的小麦品种可望为品质较好的品种.     

西北春麦区小麦地方品种高分子量麦谷蛋白亚基组成分析

为了给品质改良提供基础材料,并了解西北春麦区小麦地方品种的遗传多样性,采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)方法,分析了493份小麦地方品种的高分子量麦谷蛋白亚基(HMW-GS)的组成.结果表明:在供试材料中,Glu-1位点共有26个等位基因,其中Glu-A1位点3个,Glu-B1位点9个,Glu-D1位点14个,亚基null、7+8、2+12在各自的位点上出现频率最高,分别达到了94.53%、92.92%、86.24%;亚基组成类型共有30种,主要为null/7+8/2+12,频率达79.76%;同时筛选出一些含有1、2*、13+16、14+15、5+10、1.5+10等优质亚基或亚基对的材料,可作为优质基因源;西北春麦区小麦地方品种间Glu-1位点的遗传多样性,以Glu-D1位点最高,其次是Glu-B1位点,Glu-A1位点最低.     

西藏半野生小麦高分子量麦谷蛋白亚基组成分析

应用SDS-PAGE分析了50份西藏半野生小麦(Triticum aestivum ssp.tibetanum Shao)的高分子量麦谷蛋白亚基等位基因组成。结果表明,43份材料的HMW-GS组成是同质的,7份材料为异质。供试材料共有7种HMW GS组合,以Null、7 8、2 12为主要类型,占所分析材料的68．4％。在Glu-1位点共检测到10种等位基因,Glu- A1位点2种,Glu～B1位点4种,Glu～D1位点4种。Null(96％)、7 8(80．4％)和2 12(94．9％)分别是Glu-A1、 Glu-B1和Glu～D1位点上主要的等位基因。在Glu-B1位点还新发现2个亚基,暂时分别命名为8*和7**。说明西藏半野生小麦中存在着较广泛的HMW-GS等位基因变异,是小麦品质育种潜在的可利用的遗传资源。     

湖北推广小麦品种(系)高分子量麦谷蛋白亚基组成分析

应用SDS-PAGE技术分析了45份湖北推广小麦品种(系)籽粒的高分子量麦谷蛋白亚基组成。40份材料的高分子量麦谷蛋白亚基组成为同质,5份为异质。在Glu-1位点共检测到9种等位基因变异类型,其中Glu-A1位点有“1、2^ 、Null”3种变异类型,Glu-B1位点有“7、7 8、7 9、14 15”4种,Glu-D1位点有“2 12、5 10”2种。“Null、7 8、2 12”是主要亚基,它们的频率分别是62．5％、60％和72．5％。亚基组合类型有12种,其中(Null,7 8,2 12)亚基组合占30．0％,(1,7 8,2 12)、(1,14 15,2 12)、(Null,7 9,2 12)、(Null,7 8,5 10)4种组合的频率都在10％以上,这5种亚基组合占总组合的72．5％。供试小麦材料品质评分在5～10之间,平均评分为7．0。含5 10亚基的品种(系)所占比例低,是湖北小麦烘烤品质较差的部分原因。     

小麦新品种(系)Glu-1位点等位基因变异研究

应用SDS-PAGE技术分析了40份小麦新品种(系)的高分子量麦谷蛋白亚基等位基因变异。在Glu-1位点共检测到10种变异类型,其中Glu-Al位点有3种类型：Null、1、26 ,Glu-B1位点有5种类型：7 8、7 9、14 15、7、17 18,Glu-D1位点有2种类型：2 12、5 10;Null(54．3％)、7 8(51．4％)和2 12(62．9％)分别是Glu-Al、Glu-B1和Glu-D1位点上的主要亚基变异类型。另外,在2份材料的Glu-B1和Glu-D1位点各检测到1个新的亚基,分别命名为1By8．1和1Dx5^ 。Glu-1位点的Nei‘s遗传变异指数平均为0,5648,Glu-B1的遗传多样性最高,Glu-D1最低。供试小麦材料Glu-1位点的HMW-GS组合共有17种类型,以(Null,7 8,2 12)组合为主要类型,占31．4％;有9种亚基组合类型分别只在1份材料中出现,占26.1％。结果表明,这些小麦新品种(系)存在着丰富的亚基组合类型。     

外引小麦种质资源HMW-GS组成及品质评价

为有效利用外引小麦种质资源,本研究对引自国际玉米小麦改良中心、法国、巴基斯坦等区域的393份小麦种质资源进行高分子量麦谷蛋白亚基组成及品质性状的分析,结果表明,在供试材料中共检测到23种亚基类型和50种亚基组合类型;资源品质评分在4～10分之间,平均为7.68分,其中品质评分为10分、9分、8分的材料分别有74份、76份、96份,包含的亚基组合类型分别有8种、2种、14种,品质评分为8分及以上的材料共计246份,占总材料的62.6%;此外,9份材料检测出新的亚基及组合类型:F14(2*,14*+15*/6*+16*,Null)、F33(2*,14*+15*/6*+16*,Null)、C119(1,7*+16*,5+10)、C120(Null,7*+16*,5+10)、C125(2*,7+8,5′+10)、C51(2*,7+9,5′+10)、O13(2*,7+16,2+12)、O17(2*,7+16,2+12)和P27(2*,7+18,2+12)。总体上这些外引材料优质亚基分布频率高、组合类型丰富,可作为优异资源进一步开发利用,并为我国小麦品质改良提供材料基础及理论依据。     

西南冬麦区地方品种HMW-GS组成遗传多样性研究

采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)对西南冬麦区(云南、贵州、四川)3个省份共计560份小麦地方品种的高分子量谷蛋白亚基(HMW-GS)组成进行了研究。结果表明:Glu-1位点共有22种等位基因,其中Glu-A1位点4种、Glu-B1位点11种、Glu-D1位点7种;亚基null、7 8和2 12在各自位点的频率最高,分别为89.64%、68.21%和96.43%。亚基组成类型共有46种,以null/7 8/2 12和null/7 9/2 12为主,频率分别为50.89%和11.79%。在这些材料中筛选出一些含有1、2*、17 18、14 15、5 10等优质亚基的材料,其中有52份材料含有优质亚基组合。     

云南铁壳麦高分子量麦谷蛋白亚基组成及其遗传多样性分析

以36份云南铁壳麦为试验材料,采用SDS-PAGE法分析了Glu-1位点编码的高分子量麦谷蛋白亚基(HMW-GS)及组成。结果表明,在Glu-A1位点上检测到3种(N,2*和1)亚基类型,Glu-B1位点上共检测到5种(7、7 8、17 18、13 16和6 8)亚基类型,Glu-D1位点上只检测到1种(2 12)亚基类型。共检测到6种亚基组成类型,即:N、7、2 12,N、7 8、2 12,2*、7 8、2 12,2*、17 18、2 12,1、6 8、2 12和1、13 16、2 12。云南铁壳麦的HMW-GS为普通小麦已知变异类型的18%,3个位点的Nei's遗传变异系数顺序为Glu-B1(0.5734)>Glu-A1(0.2484)>Glu-D1(0),表明云南铁壳麦属较原始类型,Glu-D1位点未发生变异。品质评分最高分为8分(3份材料),平均为5.2分。同时86%的云南铁壳麦具有适合制作优质手工馒头的高分子量麦谷蛋白亚基(N和2 12),42%的云南铁壳麦具有亚基组成类型(1、7 8、2 12和N、7 8、2 12),这些材料可作为云南小麦馒头品质改良的材料。     

青海省小麦品种阿勃高分子量麦谷蛋白遗传多样性研究

为了研究小麦品种阿勃在青海省不同生态区种植的广适性,本试验采用十二烷基硫酸钠聚丙烯酰胺凝胶电泳(SDSPAGE)技术,以青海省不同生态区15份阿勃为材料进行高分子量麦谷蛋白亚基(HMW-GS)的遗传多样性分析。结果表明:阿勃HMW-GS的亚基组合类型有8种,主要为1/7+8/2+12;有11种亚基,各个亚基出现的频率范围6.67%~100%;Glu-B1位点遗传多样性指数较大,为0.239;供试材料群体间GS的变化范围为0.35~1.00,平均为0.675,所有阿勃聚为3类,其中13份阿勃材料聚在第Ⅰ类,另2份分别聚在第Ⅱ和第Ⅲ类,说明在青海不同生态区本土种植保留下的阿勃HMW-GS遗传多样性丰富。     

67份美国小麦种质资源的HMW-GS组成与品质分析

为了挖掘新的种质资源,对引自美国的67份小麦种质材料进行了高分子量麦谷蛋白亚基组成与品质性状分析。HMW-GS组成分析表明,在供试材料中共检测到20种亚基类型和25种亚基组合,表明这批材料的遗传多样性较高。在GluA1位点上,亚基1与2*的出现频率分别为16.4%与35.8%;Glu-B1位点有9个等位变异,其中出现频率最高的为7+9亚基对(47.8%);Glu-D1位点有8个等位变异,以5+10亚基对为主要类型,出现频率高达74.6%。在Glu-B1位点上发现3个不常见亚基7*、8*、8**和3个未知亚基a、b、c,还发现1个未知亚基,暂时将其标记为5*,可能位于Glu-D1位点上。亚基组合类型中,"null,7+8,5+10"的出现频率最高,为22.4%。亚基评分在5~10分之间,平均8.2分,得分在8分及其以上的材料有42份(62.69%),其中得10分的材料有9份(13.43%)。利用DA7200近红外成分分析仪对这批小麦材料的品质性状进行初步分析,结果表明其品质指标较低。这67份美国小麦材料含有的优质亚基比例较高,可作为中间材料以改良我国黄淮麦区小麦品种的亚基组成。     

Molecular marker-assisted selection of HMW glutenin alleles related to wheat bread quality by PCR-generated DNA markers

While quality in hexaploid wheat (Triticum aestivum L. em Thell.) is a very complex trait, it is known that the water-insoluble gluten proteins are responsible for the elasticity and chohesiveness (strength) of dough and are therefore important determinants of breadmaking quality. High-molecular-weight (HMW) glutenin subunits encoded by genes on the long arm of group 1 chromosomes have been associated with gluten strength, and a portion of the variability between cultivars can be attributed to glutenin subunit composition. Good or poor wheat breadmaking quality is associated with two allelic pairs at the Glu-D1 complex locus, designated 1Dx5–1Dy10 and 1Dx2–1Dy12, respectively. Among the HMW glutenin subunits encoded at Glu-B1, Bx7 is quite common, being associated with either of two subunits, By8 or By9. Both allelic pairs contribute moderately well to good breadmaking quality by increasing dough elasticity. Glutenin subunit screening is accomplished using electrophoresis (SDS-PAGE). In this paper, I report the development of an alternative screening method based on glutenin genes themselves using the polymerase chain reaction (PCR). This easy, quick and non-destructive PCR-based approach is an efficient alternative to standard procedures for selecting bread-wheat genotypes with good breadmaking characteristics. Received: 14 August 1999 / Accepted: 21 March 2000     

Expression of epitope-tagged LMW glutenin subunits in the starchy endosperm of transgenic wheat and their incorporation into glutenin polymers

The low-molecular-weight (LMW) glutenin subunits are components of the highly cross-linked glutenin polymers that confer viscoelastic properties to gluten and dough. They have both quantitative and qualitative effects on dough quality that may relate to differences in their ability to form the inter-chain disulphide bonds that stabilise the polymers. In order to determine the relationship between dough quality and the amounts and properties of the LMW subunits, we have transformed the pasta wheat cultivars Svevo and Ofanto with three genes encoding proteins, which differ in their numbers or positions of cysteine residues. The transgenes were delivered under control of the high-molecular-weight (HMW) subunit 1Dx5 gene promoter and terminator regions, and the encoded proteins were C-terminally tagged by the introduction of the c-myc epitope. Stable transformants were obtained with both cultivars, and the use of a specific antibody to the c-myc epitope tag allowed the transgene products to be readily detected in the complex mixture of LMW subunits. A range of transgene expression levels was observed. The addition of the epitope tag did not compromise the correct folding of the trangenic subunits and their incorporation into the glutenin polymers. Our results demonstrate that the ability to specifically epitope-tag LMW glutenin transgenes can greatly assist in the elucidation of their individual contributions to the functionality of the complex gluten system.Communicated by J. W. Snape     

Bánkúti 1201—an old Hungarian wheat variety with special storage protein composition

Bánkúti 1201, an old Hungarian wheat variety with special quality traits, was analysed to determine the relationships between its storage protein composition and superior quality-attributes for breadmaking. Based on the storage protein composition, the variety appears to have the nature of a population, containing several genotypes with different gluten protein alleles. Using molecular markers, a new mutant x-type HMW glutenin allele was identified, containing an extra cysteine residue and showing a moderate, positive-effect on gluten properties. In lines possessing subunits Bx7+By8 the overexpression of the Bx-type subunit could be detected, resulting in a higher unextractable polymeric protein (UPP) content and increased dough strength. It was found that the presence or absence of subunit Bx7 has an equilibrating effect on the dough extensibility, which is generally characteristic of the Bánkúti 1201 population. The complex good bread-making quality of the variety, which has strong but highly extensible dough, is probably due to the balance between lines which express subunit Bx7 and those which do not.     

烟草花粉原生质体与叶肉原生质体的融合及培养早期变化

用ＰＥＧ—高Ｃａ高ＰＨ法诱导抗卡那霉素的烟草（Ｎｉｃｏｔｉａｎａｔａｂａｃｕｍ）品系Ｎ３６４＋Ｋｍ＋花粉原生质体和黄花烟草（Ｎｉｃｏｔｉａｒｕｓｔｉｃａ）叶肉原生质体融合。幼嫩花粉原生质体和叶肉原生质体之间的融合体培养启动胚胎发生分裂,经卡那霉素筛选后,少数多细胞团存活并形成小愈伤组织。成熟花粉原生质体与叶肉原生质体之间的融合体则仅产生管状结构。这一结果表明,作为融合一方的花粉原生质体的发育时期对融合产物的发育途径有重要影响。     

Modification of the Low Molecular Weight (LMW) Glutenin Composition of Transgenic Durum Wheat: Effects on Glutenin Polymer Size and Gluten Functionality

The low-molecular weight (LMW) glutenin subunits are major determinants of the viscoelasticity of durum wheat gluten, and therefore of its technological quality, with both quantitative effects and qualitative effects. We have modified the LMW glutenin subunit composition of the durum wheat cultivar Ofanto by expression of a transgene encoding a B-type LMW glutenin subunit and have carried out detailed analyses of two independent transformed lines in order to assess the effect of the transgene on the size distribution of the glutenin polymers and on their functional properties. In one line the expression of the transgene led to an increase in the amount of large glutenin polymers resulting in stronger and more stable dough. In the second line, however, the expression of the transgenic subunit was accompanied by decreased expression of endogenous LMW subunits with consequent detrimental effects on glutenin polymers and dough viscoelasticity. These results demonstrate that the LMW glutenin subunits contribute to the functional properties of wheat by influencing the amount and the distribution of glutenin polymers and indicate that either plant breeding or GM technology can be used to 'fine tune' the properties of durum wheat for different end uses by manipulating the amount and structures of individual LMW subunit proteins.     

The Interactive Effects of Transgenically Overexpressed 1Ax1 with Various HMW-GS Combinations on Dough Quality by Introgression of Exogenous Subunits into an Elite Chinese Wheat Variety

Seed storage proteins in wheat endosperm, particularly high-molecular-weight glutenin subunits (HMW-GS), are primary determinants of dough properties, and affect both end-use quality and grain utilization of wheat (Triticum aestivum L). In order to investigate the interactive effects between the transgenically overexpressed 1Ax1 subunit with different HMW-GS on dough quality traits, we developed a set of 8 introgression lines (ILs) overexpressing the transgenic HMW-glutenin subunit 1Ax1 by introgression of this transgene from transgenic line B102-1-2/1 into an elite Chinese wheat variety Chuanmai107 (C107), using conventional crossing and backcrossing breeding technique. The donor C107 strain lacks 1Ax1 but contains the HMW-GS pairs 1Dx2+1Dy12 and 1Bx7+1By9. The resultant ILs showed robust and stable expression of 1Ax1 even after five generations of self-pollination, and crossing/backcrossing three times. In addition, overexpression of 1Ax1 was compensated by the endogenous gluten proteins. All ILs exhibited superior agronomic performance when compared to the transgenic parent line, B102-1-2/1. Mixograph results demonstrated that overexpressed 1Ax1 significantly improved dough strength, resistance to extension and over-mixing tolerance, in the targeted wheat cultivar C107. Further, comparisons among the ILs showed the interactive effects of endogenous subunits on dough properties when 1Ax1 was overexpressed: subunit pair 17+18 contributed to increased over-mixing tolerance of the dough; expression of the Glu-D1 allele maintained an appropriate balance between x-type and y-type subunits and thereby improved dough quality. It is consistent with ILs C4 (HMW-GS are 1, 17+18, 2+12) had the highest gluten index and Zeleny sedimentation value. This study demonstrates that wheat quality could be improved by using transgenic wheat overexpressing HMW-GS and the feasibility of using such transgenic lines in wheat quality breeding programs.     

“龙麦15”2＋12与5＋10亚基近等基因系面粉品质差异的研究

通过对小麦栽培品种龙麦１５中的同形小种进行ＳＤＳ－ＰＡＧＥ和Ａ－ＰＡＧＥ的分析,在国内首次获得了一对Ｇｌｕ－Ｄ１位点高分子量麦谷蛋白亚基分别为２＋１２和５＋１０的近等基因系。对该近等基因系面粉品质的分析表明,带有５＋１０亚基的龙麦１５比事有２＋１２亚基的龙麦１５的Ｚｅｌｅｎｙ沉淀值高１２％,沉淀值／湿面筋的比值由１．０３提高到１．３２。该实验结果证明,５＋１０亚基对面粉品质贡献确实优于２＋１２亚基     

Altered functional properties of tritordeum by transformation with HMW glutenin subunit genes

The high-molecular-weight (HMW) subunits of wheat glutenin are the major determinants of the gluten visco-elasticity that allows wheat doughs to be used to make bread, pasta and other food products. In order to increase the proportions of the HMW subunits, and hence improve breadmaking performance, particle bombardment was used to transform tritordeum, a fertile amphiploid between wild barley and pasta wheat, with genes encoding two HMW glutenin subunits (1Ax1 and 1Dx5). Of the 13 independent transgenic lines recovered (a transformation frequency of 1.4%) six express the novel HMW subunits at levels similar to, or higher than, those of the endogenous subunits encoded on chromosome 1B. Small-scale mixograph analysis of T₂ seeds from a line expressing the transgene for 1Dx5 indicated that the addition of novel HMW subunits can result in significant improvements in dough strength and stability, thus demonstrating that transformation can be used to modify the functional properties of tritordeum for improved breadmaking. Received: 15 January 1999 / Accepted: 5 February 1999