圆锥小麦（Triticum turgidumL．）贮藏蛋白的遗传多样性研究

为发掘可供利用的优异基因资源,采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和酸性聚丙烯酰胺凝胶电泳（APAGE）对来自17个国家和地区的95份圆锥小麦的贮藏蛋白进行了分析。结果表明,圆锥小麦贮藏蛋白位点存在丰富的遗传多样性。供试材料中共检测到17种高分子量麦谷蛋白亚基和34种亚基组合类型,其中亚基1和7＋8分别为Glu-A1和Glu-B1位点优势亚基,也检测到优质亚基14＋15和17＋18。亚基组合1／7＋8和null／7＋8虽为优势组合,但所占频率低;醇溶蛋白检测共分离出29条多态性带纹,其中每份材料可分离出5～20条,平均12条,平均遗传相似系数为0．471。供试材料在0．402水平上可分为五类,其聚类结果与材料来源地并不完全一致。试验结果表明,中国圆锥小麦地方品种在高分子量麦谷蛋白亚基表现上具有独特性。     

Significance of LMW-GS and HMW-GS for Dough Extensibility: «Addition» versus «Incorporation» Protocols

Low molecular weight (LMW-GS) and high molecular weight glutenin subunits (HMW-GS) were added to a base flour using both «addition» and «incorporation» protocols. «Incorporation» of glutenin subunits into the glutenin network of the base flour was performed by partial (reversible) reduction and subsequent reoxidation of the glutenin network in the presence of the added glutenin subunits whereas, in the «addition» protocol, glutenin subunits were added without reduction/oxidation. The effects of both «addition» and «incorporation» of alkylated and unalkylated LMW-GS and HMW-GS on dough extension parameters maximum resistance (MR) and extensibility (EX) were compared and thoroughly discussed. HMW-GS and LMW-GS had totally different effects on dough extensibility. «Addition» of LMW-GS significantly decreased both MR and EX whereas HMW-GS caused a significant increase in MR. «Incorporation» of LMW-GS caused a decrease in MR whereas HMW-GS clearly increased MR. The similarity in effects obtained with «addition» and «incorporation» of glutenin subunits indicated that, even with «addition», glutenin subunits can be partially incorporated into the glutenin network in the presence of oxygen. Alkylated and unalkylated glutenin subunits had different effects. This was probably caused by the effect of free sulphydryl groups in unalkylated subunits (possibility of SS/SH exchanges and/or incorporation) and/or the effect induced by introduction of alkylated derived substituents. A protocol for «incorporation with excess KIO₃» was developed to exclude the possible effect of a lowering of the available oxidant concentration by oxidation of free sulphydryl groups in glutenin subunits. However, the use of high levels of oxidant in the «incorporation with excess KIO₃» protocol seems to overrule the effects of added glutenin subunits or may force glutenin subunits to incorporate differently from what can be observed under gentle oxidation conditions. Therefore, «incorporation with excess KIO₃» is not suitable for studying the effects of incorporation of glutenin subunits on dough extensibility.     

四川小麦品种高、低分子量麦谷蛋白基因和1B/1R易位的分子标记鉴定

为给四川小麦品质育种提供参考信息,利用7个HMW-GS、17个LMW-GS和1个1B/1R易位的特异分子标记,对105份2000年后育成的四川小麦品种进行上述基因检测。结果表明:(1)针对HMWGS,在Glu-A1位点,含Ax2*的品种有2份,频率为1.9%;在Glu-B1位点,含Bx7、Bx20、Bx17、By8和By9的品种分别有73、26、4、45和30份,频率分别为69.5%、24.8%、3.8%、42.9%和28.6%,未检测到含Bx7OE的品种;在Glu-D1位点,含Dx5的品种有65份,频率为61.9%。(2)针对LMW-GS,在Glu-A3位点,含Glu-A3a、Glu-A3b、Glu-A3c、Glu-A3d和Glu-A3f的品种分别有2、2、63、29和9份,频率分别为1.9%、1.9%、60.0%、27.6%和8.6%,未检测到含Glu-A3e和Glu-A3g的品种;在Glu-B3位点,含Glu-B3b、Glu-B3d、Glu-B3f、GluB3g和Glu-B3i的品种分别有18、10、1、75和1份,频率分别为17.1%、9.5%、1.0%、71.4%和1.0%,未检测到含Glu-B3a、Glu-B3c、Glu-B3e和Glu-B3h的品种。(3)含1B/1R易位的品种有36份,频率为34.3%。(4)组合6种和5种以上优质基因的品种分别有2份(频率为3.8%)和15份(频率为14.3%)。可利用这些品种作为亲本,在四川小麦品质育种中逐步导入优质基因Ax2*、Bx7、By8、Dx5、Glu-A3d、Glu-B3d、Glu-A3b和Glu-B3b,并淘汰1B/1R易位,优化四川小麦面筋优质基因组成。     

Relationships between dough strength,polymeric protein quantity and composition for diverse durum wheat genotypes

Five different Glu-B1 HMW-GS patterns were identified among a collection of diverse durum wheat genotypes grown in 2001 in two locations in western Canada. The durum wheat lines exhibited a wide range of dough and gluten strength characteristics as measured by alveograph and 2 g mixograph parameters, gluten index (GI), and protein composition as measured by unextractable polymeric protein (UPP) content and the ratio of high-molecular weight (HMW) glutenin subunits (GS) to low-molecular weight (LMW) GS. HMW-GS subunits patterns represented within the genotypes were 6+8, 7+8, 7+16, 14+15 and 20. Two of the genotypes expressed Glu-A1 HMW-GS 2* in combination with other HMW-GS. Approximately 95% of the durum genotypes were γ-gliadin 45 types. Analysis of variance indicated that genotype was a greater source of variation in all measurements than was growing location, with the exception of protein content which showed less variation contributed by genotype and more contributed by location than for other quality parameters. UPP was strongly associated with all strength measurements. All of the γ-gliadin 42 types were low in UPP and weak. Among the γ-gliadin 45 types, those possessing HMW-GS 20 were typically in the lower half of the UPP and strength range. There was no clear evidence of an association between any of the other HMW-GS patterns and gluten strength. The majority exhibited HMW to LMW-GS ratios that were within the relatively narrow range of 0.15–0.25, yet there were wide variations in dough strength among genotypes within that range. Increasing proportions of HMW-GS resulting in ratios of greater than 0.30 were generally associated with weak dough and gluten and low UPP content.     

HMW-GS分子标记多重PCR体系的建立及新疆春小麦的检测

为给新疆优质春小麦品种选育提供参考依据,利用小麦优质高分子量谷蛋白亚基(HMW-GS)基因的特异性标记,基于17份已知HMW-GS组成的品种(系),构建了3套多重PCR,体系Ⅰ可用于同时检测AxNull和Dx5基因,体系Ⅱ可同时检测Ax2*和By8基因,体系Ⅲ可同时检测Bx14和Dx5基因;用3套多重PCR体系分别检测...     

Isolation and Characterisation of Single Chain Amylose

Five amylose preparations of different origins (cassava, potato, smooth seeded pea, wheat and maize), obtained from native starch granules by thymol complexation, were ultracentrifuged as the final decontamination step to remove a high molecular weight population contaminating the amylose solutions. The efficiency of this ultracentrifugation procedure was assessed by dynamic light scattering (DLS): decreases in apparent hydrodynamic radii,R?_H, from 46·1–72·6 nm before ultracentrifugation to 16·1–29·3 nm after were observed. Amylose solutions were then characterised by size exclusion chromatography coupled on-line to multi-angle laser light scattering (SEC–MALLS). Under these conditionsM?_wof cassava, potato, smooth seeded pea, wheat and maize amyloses were, respectively, 1·05×10⁶, 7×10⁵, 6·2×10⁵, 5·1×10⁵and 3·4×10⁵g/mol. Using a specific optimisation algorithm, experimental molecular weight distributions (MWD) were fitted by two mathematical models of ‘Most Probable’ distribution and ‘log-normal’ distribution. The best fit was obtained for the second model, but fittedM?_wwere higher than experimentalM?_w. When a ‘Most Probable’ model was used, the fittedM?_wwere consistent with experimentalM?_wbut with a lower quality of fit. Exponentscin the power lawR_G=KM^cwere between 0·6 and 0·7, indicating an extended linear random coil in the range of MW analysed (3×10⁵–9×10⁶g/mol). This procedure was also applied to the characterisation of different commercial amylose products.     

小麦显性矮源对株粒重及产量构成因素的影响

利用8个普通小麦品种与5个不同显性矮源进行回交产生的8套近等基因系，进行了株粒重及产量构成因素的研究，结果表明，显性矮源对有效穗数没有显著影响，对株粒重、穗粒数和千粒重都有显著的降低作用，降幅最小的是具有奥尔森矮源的近等基因系，分别降低19．6％、26．9％和10．5％；降幅最大的是具有矮变1号矮源的近等基因系，分别降低68．9％、66．7％和24．7％。携带Rht10基因的西农02和矮变1号矮源转育的近等基因系之间的株粒重、穗粒数和千粒重的差异都显著或极显著，说明它们对普通小麦品种的影响不一致。具有显性矮源的近等基因系株粒重偏低的主要原因是穗粒数减少和千粒重降低。具有显性矮源近等基因系的株粒重与株高的回归分析表明，适当提高显性矮源的株高可以提高株粒重。     

乌拉尔图和栽培一粒小麦抗病基因向普通小麦转移的研究

乌拉尔图小麦（Triticum urartu Tum．）和栽培一粒小麦（Triticum monococcum L．）是普通小麦的两个二倍体野生种，是进行小麦遗传改良的重要遗传资源。为了将其抗白粉病和抗条锈病基因转移到普通小麦中，用普通小麦分别与两份乌拉尔图小麦材料1010013和1010015及一份栽培一粒小麦材料1010048配制杂交组合。结果表明，乌拉尔图小麦与普通小麦杂交不能正常结实，必须进行幼胚拯救。成胚率为14．77％；而栽培一粒小麦与普通小麦杂交可正常结实，但结实率很低。杂种F1自交不育，与普通小麦回交可正常结实．但BC1自交结实率极低。对普通小麦与乌拉尔图小麦杂种F1花粉母细胞减数分裂中期Ⅰ的观察结果表明，平均单价体为17．36个．二价体为5．32个。进一步对杂种后代进行抗病鉴定和遗传分析，乌拉尔图小麦1010013和1010015分别含有一对显性抗白粉病基因。栽培一粒小麦1010048含有两对独立遗传的显性抗条锈病基因，并分别在杂种后代BC2F1和BC1F2中获得了染色体正常（2n=42）、细胞学稳定且抗性与供体亲本一致的抗白粉病和抗备锈病植株。说明来自二倍体乌拉尔图和栽培一粒小麦的抗病基因已通过遗传重组导入到普通小麦中。研究还发现普通小麦莱州953与乌拉尔图小麦和栽培一粒小麦杂交的结实率与中国春的同样高，表明其可能携带有远缘杂交亲和基因。     

菠萝果重与营养器官的相关性分析

用回归和相关分析法对菠萝果重与营养器官的相关性进行了研究。结果表明:菠萝果重与茎叶重量的相关关系达到极显著水平。茎叶越重,果实就越大越重。果重与裔芽数、裔芽重量、吸芽数、吸芽重和冠芽重等营养芽均呈正相关,其中,果重与裔芽重关系最为密切,与裔芽数次之,都达极显著水平;但在排除茎叶重的影响后,对果重与营养芽的关系进行偏相关分析表明,果重与冠芽重、裔芽数、裔芽重、吸芽数、吸芽重均未达到显著的相关水平。在茎叶重一定的情况下,果重与裔芽数、裔芽重量和吸芽重及冠芽重的关系不大。不同菠萝种类、不同杂交种其营养芽的数量不等。大果类型其营养芽的数量明显少于小果类型,应是一种遗传特性;此外,裔芽与吸芽间存在负相关关系。因此,在菠萝生产中除芽是否能达到显著增产,有待进一步研究。      

普通小麦与Elymus rectisetus衍生后代的细胞遗传学和形态学研究

披碱草（Elymus rectisctus,以下简写为E．rectiselus)具有二倍性无融合生殖特性,为了获得小麦-E．rectisetus稳定的异附加系或异代换系,对(小麦-E．rectiselus)BC2F2衍生后代的细胞学和形态学进行了研究。结果表明,在BC2F5～BC2F7镜栓的单株中,体细胞染色体数目在22～50条之间,其中42条和44条染色体所占的比例最大,分别占鉴定植株总数的38．0％和35．9％。三个2n=42=21″的稳定株系与普通小麦Fukuhokomugi杂交F1的花粉母细胞染色体构型为2n=18″ 6′,表明有三对E．rectiselus染色体代换到普通小麦中;三个2n=44=22″的稳定株系与Fukuhokomugi杂交F1的花粉母细胞染色体构型为21″ 1′,表明它们为二体异附加系。此外,衍生后代的形态学特征趋向于普通小麦。     

小麦 Glu A1位点1亚基和Null亚基间品质效应的差异

为了解小麦Glu-A1位点1亚基和Null亚基间的品质效应差异,用郑麦9405/郑麦98//周麦16配制杂交组合,利用系谱法辅助生化标记连续多代选择后得到纯合的1亚基和Null亚基的近等基因系,并对近等基因系1亚基和Null亚基间的面筋特性和粉质特性进行了测定和分析.结果表明,对于面筋指数、形成时间、稳定时间和粉质质量指数,1亚基的贡献明显大于Null亚基,1亚基比Null亚基的面筋指数、形成时间、稳定时间和粉质质量指数分别提高9.79％、68.73％、25.89％和13.99％,成组数据的t测验显示差异达到极显著水平(P值分别为0.007、0.000、0.002和0.006),亚基效应为1亚基＞Null亚基;对于湿面筋含量、干面筋含量和吸水率,1亚基和Null亚基的贡献无明显差别,成组数据t检验显示差异不显著(0.978、0.654和0.206).     

Molecular Weight-Dependent Immunostimulative Activity of Low Molecular Weight Chitosan via Regulating NF-κB and AP-1 Signaling Pathways in RAW264.7 Macrophages

Chitosan and its derivatives such as low molecular weight chitosans (LMWCs) have been found to possess many important biological properties, such as antioxidant and antitumor effects. In our previous study, LMWCs were found to elicit a strong immunomodulatory response in macrophages dependent on molecular weight. Herein we further investigated the molecular weight-dependent immunostimulative activity of LMWCs and elucidated its mechanism of action on RAW264.7 macrophages. LMWCs (3 kDa and 50 kDa of molecular weight) could significantly enhance the mRNA expression levels of COX-2, IL-10 and MCP-1 in a molecular weight and concentration-dependent manner. The results suggested that LMWCs elicited a significant immunomodulatory response, which was dependent on the dose and the molecular weight. Regarding the possible molecular mechanism of action, LMWCs promoted the expression of the genes of key molecules in NF-κB and AP-1 pathways, including IKKβ, TRAF6 and JNK1, and induced the phosphorylation of protein IKBα in RAW264.7 macrophage. Moreover, LMWCs increased nuclear translocation of p65 and activation of activator protein-1 (AP-1, C-Jun and C-Fos) in a molecular weight-dependent manner. Taken together, our findings suggested that LMWCs exert immunostimulative activity via activation of NF-κB and AP-1 pathways in RAW264.7 macrophages in a molecular weight-dependent manner and that 3 kDa LMWC shows great potential as a novel agent for the treatment of immune suppression diseases and in future vaccines.     

红小豆、大豆、菜豆的粒重和初期生育的相关性

红小豆在3叶期的叶面积和个体重中为最小，菜豆最大。3种豆类的两种性状与粒重之间都呈现了很高的正相关关系。但是，3叶期的叶面积和干物重的增加速度与粒重之间只有大豆呈有意正相关关系，红小豆和菜豆没有有意相关关系。本研究显示了出苗后的红小豆初期生育状况不如大豆和菜豆。从以上的结果可以判断粒重对叶面积以及干物重的影响到3叶期为止。     

安徽省小麦产业体系展示品种HMW-GS组分及GMP的研究

为了解安徽省淮北及黄淮麦区的小麦加工品质,以52个安徽省小麦产业体系展示品种为材料,分析了供试小麦品种HMW-GS的组成和分布、谷蛋白聚合体(GMP)含量、小麦蛋白质含量、Zeleny沉降值及湿面筋含量。结果表明,52个供试小麦品种的HMW-GS变异类型众多,共发现13种变异类型,包含6种优质亚基类型;共出现了21种HMW-GS组合。按照GMP、蛋白质、湿面筋含量及Zeleny沉降值可将52个供试品种分为4类。供试品种的品质评分介于4~10分之间,平均7.4分。基因位点Glu-A1含有1亚基的品种,GMP含量高于含有Null亚基的品种。     

Effect of high molecular weight glutenins and rye translocations on soft wheat flour cookie quality

The influence of high molecular weight glutenin subunits (HMW-GS) on wheat breadmaking quality has been extensively studied but the effect of different Glu-1 alleles on cookie quality is still poorly understood. This study was conducted to analyze the effect of HMW-GS composition and wheat-rye translocations on physicochemical flour properties and cookie quality of soft wheat flours. Alleles encoded at Glu-A1, Glu-B1 and Glu-D1 locus had a significant effect over physicochemical flour properties and solvent retention capacity (SRC) profile. The null allele for Glu-A1 locus presented the highest cookie factor observed (CF = 7.10), whereas 1BL/1RS and 1AL/1RS rye translocations had a negative influence on CF. The three cultivars that showed the highest CF (19, 44 and 47) had the following combination: Glu-A1 = null, Glu-B1 = 7 + 8, Glu-D1 = 2 + 12 and no secalins. Two prediction equations were developed to estimate soft wheat CF: one using the HMW-GS composition and the other using physicochemical flour parameters, where SRCsuc, SRC carb, water-soluble pentosans, damaged starch and protein turned out to be better CF predictors. This data suggests that grain protein allelic composition and physicochemical flour properties can be useful tools in breeding programs to select soft wheat of good cookie making quality.     

Correspondence between two minor Glu-A3 genes of durum wheat and their encoded polypeptides by using a proteomic approach

The low molecular weight glutenin subunits (LMW-GS) are wheat storage proteins participating to the formation of glutenin polymers that, along with the other gluten proteins, allow the accumulation of a large quantity of protein in the endosperm tissue. The size and composition of the glutenin polymers are directly related to gluten visco-elastic properties. In particular, LMW-GS composition is the factor most influencing durum wheat quality.     

普通小麦F1代籽粒高分子量谷蛋白亚基的遗传表现

为给小麦品质改良提供依据,采用SDS-PAGE方法,以来自国内外的6个小麦品种（系）为材料,分析了15个杂交组合F1代高分子量谷蛋白亚基（HMW-GS）的遗传表现。结果表明：①HMW-GS在F1代的遗传具有剂量效应,即部分正反交组合F1代籽粒中同一亚基带的颜色深浅不同,来自母本的亚基带比来自父本的亚基带颜色深,说明来自母本的亚基比来自父本的亚基含量高;②2个国内与国内品种间的杂交组合及2个国外与国外品种间的杂交组合,其F1代HMW-GS均表现为完全共显性,11个国内和国外品种间的杂交组合,有4个组合的F1代出现了HMW-GS的不完全表达,缺失率占11个组合总数的36％。     

南疆小麦品种(系)的HMW-GS组成及分布

为了给新疆优质小麦品种的选育和改良提供科学依据，应用SDS-PAGE方法对来源于南疆的169个小麦品种(系)的HMW-GS组成与分布进行了系统分析。结果表明，Glu-A1住点有两种等位变异类型Null和1；Glu-B1住点有7、7 8、7 9、6 8、17 18、14 15、21共7种等住变异类型，且主要以7 8和7 9为主；Glu-D1位点有2 12、4 12、5 i0、2 10、2．2 12共5种等位变异类型，且以2 12和5 10为主。本文还研究了这些HMW-GS(或组成)出现的频率和特点。     

Antithrombotic Activity of Heparinoid G2 and Its Derivatives from the Clam Coelomactra antiquata

Clam heparinoid G2 (60.25 kDa) and its depolymerized derivatives DG1 (24.48 kDa) and DG2 (6.75 kDa) prepared from Coelomactra antiquata have been documented to have excellent fibrinolytic and anticoagulant activity. In this study, to further explore the antithrombotic activity of G2, DG1 and DG2, azure A, sheep plasma, and clot lytic rate assays were used to determine their anticoagulant and thrombolytic activity in vitro. The results indicated that the anticoagulant titer of G2 was approximately 70% that of heparin and the thrombolytic activity of DG2 was greater than G2, DG1, and heparin activities. Moreover, in a carrageenan-induced venous thrombosis model, oral administration of G2 and DG1 each at 20 mg/kg and 40 mg/kg for 7 days significantly reduced blacktail thrombus formation, increased tissue-type plasminogen activator, fibrin degradation products, and D-dimer levels, decreased von Willebrand factor and thromboxane B2 levels, and restored phylum and genus abundance changes of intestinal bacteria. DG2 had no antithrombotic effect. At 20 mg/kg, G2, DG1, and heparin had comparable antithrombotic activities, and DG1 at 40 mg/kg had more muscular antithrombotic activity than G2. Thus, DG1 could be an antithrombotic oral agent owing to its more robust antithrombotic activity and lower molecular weight.