3个小麦条锈菌鉴别寄主的抗性遗传分析

根据对鉴别寄主的毒性谱,选用小麦条锈病菌生理小种2E16单孢菌系为接种病菌,鉴定了小麦务锈病菌鉴别寄主Chinese166、HeinesⅦ和Vilmorin23的抗性基因构成及其遗传特征。通过对3个鉴别寄主与感病品种铭贤169杂交,分别在苗期鉴定了亲代、F1、F2、BC1及正反交后代对小种2E16的抗性反应。结果表明：供试品种Chinese166对生理小种2E16的抗性由二对显性基因,即显性基因Yr1和另一对显性基因独立或重叠控制;HeinesⅦ对生理小种2E16的抗性由一对显性基因Yr2和一对隐性基因控制;Vilmorin23对生理小种2E16的抗性则由显性基因Yr3和一对隐性基因控制。     

普通小麦Qz180中一个抗条锈病基因的分子作图

普通小麦(Triticum aestivum L.)材料Qz180具有良好的抗条锈病特性,经基因推导发现其含有一个优良的抗条锈病的基因,暂定名为YrQz.用Qz180与感病材料铭贤169和WL1分别杂交构建了两个F2群体,用条中30号条锈菌小种对这两个群体进行的抗性测验表明,YrQz为显性单基因遗传.通过SSR和AFLP结合BSA的方法对这个基因进行了分子作图,结果鉴定出与YrQz连锁的2个SSR标记和2个AFLP标记.根据SSR标记的染色体位置,该基因被定位在2B染色体的长臂上,位于两个SSR位点Xgwm388和Xgwm526之间;两个AFLP标记P35M48(452)和P36M61(163)分别位于该基因的两侧,遗传距离分别为3.4 cM和4.1cM.     

普通小麦Qz180中一个抗条锈病基因的分子作图(英文)

普通小麦(Triticum aestivum L.)材料Qz180具有良好的抗条锈病特性,经基因推导发现其含有一个优良的抗条锈病的基因,暂定名为YrQz。用Qz180与感病材料铭贤169和WL1分别杂交构建了两个F_2群体,用条中30号条锈菌小种对这两个群体进行的抗性测验表明,YrQz为显性单基因遗传。通过SSR和AFLP结合BSA的方法对这个基因进行了分子作图,结果鉴定出与YrQz连锁的2个SSR标记和2个AFLP标记。根据SSR标记的染色体位置,该基因被定位在2B染色体的长臂上,位于两个SSR位点Xgwm388和Xgwm526之间;两个AFLP标记P35M48(452)和P36M61(163)分别位于该基因的两侧,遗传距离分别为3.4cM和4.1cM。     

小麦农家品种红麦(京2747)主效抗条锈病基因的RAPD标记

小麦农家品种红麦(京2747)可抗中国小麦条锈菌多个生理小种。遗传分析表明,该品种对于小麦条锈菌条中19号生理小种的抗性由1对显性基因控制。本研究采用铭贤169×红麦的F2分离群体建立抗、感DNA池,用RAPD方法进行DNA多态性分析。共筛选236个10碱基随机引物,其中引物S1167所扩增出的1条约245 bp的多态性DNA片段只出现在抗病DNA池和红麦中,而不出现在感病DNA池和感病品种铭贤169中。经用201株杂交F2植株对多态性DNA片段S1167245与目的基因的遗传连锁性进行分析,在164株抗病单株中有156株可稳定扩增出该特异DNA片段,而在37株感病单株中则有34株不能扩增出该特异DNA片段,经统计共有11株发生了交换,标记S1167245与目的抗病基因间的遗传距离为6.1cM。本研究得到的RAPD标记S1167245表现稳定、重复性强,可用于小麦抗锈育种中的标记辅助选择,促进红麦的抗条锈基因的利用。     

小麦抗条锈基因Yr69的连锁标记开发

抗条锈病基因Yr69对我国小麦条锈菌(Puccinia striiformis f.sp.tritici)小种具有广谱抗性,在小麦抗条锈病育种中具有重要价值.为提高分子标记辅助选择育种的效率,加快Yr69在小麦抗病育种中的应用,本研究利用条锈菌小种CYR34对包含340个小麦家系的'Taichung29/CH7086'...     

小麦新抗源贵农775抗条锈性特征与遗传分析

发掘并利用不同类型抗条锈病基因,构建区域间抗病基因多样性差异布局,是阻遏条锈菌大区域传播、实现小麦条锈病持续控制的重要策略。为了明确小麦新抗源贵农775抗条锈性特征和抗性遗传规律,为其合理布局应用提供依据,文章利用10个条锈菌菌系进行苗期分小种鉴定;构建贵农775与感病品种Avocet(S)杂交后代F2:3及回交BC1遗传群体,利用小麦条锈菌流行小种CYR32和最近发现的对Yr26基因有毒性的新致病类型CH42,对贵农775进行抗条锈性遗传分析。结果表明,贵农775对包括CH42致病类型在内的所有10个供试菌系均表现为免疫或近免疫的抗病性反应,而中国当前主要条锈病抗源品种92R137、川麦42(YrCH42)、贵农22(YrGN22)及Yr24等均不抗CH42;抗病遗传分析结果表明,贵农775对小麦条锈菌小种CYR32和CH42的抗性分别由一对显性核基因控制,并且为不同的小种专化抗性基因。     

两系杂交小麦恢复系MR168抗条锈病基因遗传分析及分子标记定位

小麦条锈病是影响杂交小麦普及推广的重要因素。文章利用基因推导法和SSR分子标记技术,研究了温光型两系杂交小麦恢复系MR168的抗条锈性遗传规律及其控制基因染色体位置。结果表明,MR168对CY29、CY31、CY32、CY33等条锈菌生理小种表现高抗至免疫;对SY95-71/MR168杂交组合的正反交F1、BC1、F2和F3群体分单株接种鉴定显示,MR168对CY32号小种的抗性受1对显性核基因控制,该抗病基因来源于春小麦品种辽春10号。利用集群分离分析法(Bulked segregant analysis,BSA)和简单重复序列(Simple sequence repeat,SSR)分子标记分析抗病亲本MR168、感病亲本SY95-71及183个F2代单株,发现了与MR168抗条锈病基因连锁的5个微卫星标记Xgwm273、Xgwm18、Xbarc187、Xwmc269、Xwmc406,并将该基因初步定位在1BS着丝粒附近,暂命名为YrMR168;构建了包含YrMR168的SSR标记遗传图谱,距离YrMR168最近的两个微卫星位点是Xgwm18和Xbarc187,遗传距离分别为1.9 cM和2.4 cM,这两个微卫星标记可用于杂交小麦抗条锈病分子标记辅助育种。     

小麦背景中来自华山新麦草的抗条锈病基因的遗传学分析和分子标记

H9020—17—5是一个通过杂交和回交选育的普通小麦—华山新麦草易位系,接种鉴定表明其对条锈病具有优良抗性。遗传学分析证明易位系H9020—17—5的抗条锈性是由单基因控制的显性性状,抗性基因来自于华山新麦草,暂定名为YrHua。为了标记这个来自华山新麦草的抗条锈病基因,利用H9020—17—5与感病小麦品种铭贤169杂交,建立了F2分离群体。应用81对AFLP引物对119个经条锈菌生理小种CY30接种鉴定的F2单株进行了分析,结果得到两个与YrHua基因连锁的AFLP标记PM14(301)和PM42(249),遗传距离分别为5．4cM和2．7cM,并分别位于目标基因的两侧。将标记片段克隆、测序后,根据序列信息和酶切位点多态性设计特异性引物,将AFLP标记PM14(301)转换成了简单的PCR标记。研究结果为标记辅助育种提供了分子选择工具,同时也为进一步精细定位和图位克隆YrHua基因奠定了基础。     

小麦农家品种大籽糙抗条锈性的遗传分析

以抗条锈病的农家品种大籽糙作父本、感病品种铭贤169作母本杂交获得F1代杂交种,F1代植株自交获得F2代种子,F1代植株与铭贤169回交获得 BC1代种子。在人工控制条件下,用我国小麦条锈菌优势小种条中28号和条中32号,分别对F1、F2、BC1代及其亲本的幼苗进行人工接种,研究了它们的抗性表现和杂交后代中抗条锈性的分离情况。结果表明,大籽糙对条中32号小种的抗性由一对隐性基因控制;对条中28号小种的抗性由一对显性基因和一对隐性基因的互补作用控制。 Abstract:Dazicao,a native wheat variety with stripe rust resistance from Henan,China,was crossed with susceptible cultivar Mingxian 169 as the female parent.The F1 progeny was selfed to produce F2 progeny and backcrossed with Mingxian 169 to produce BC1 progeny.In air-conditioned greenhouse,seedlings of the F1,F2,BC1 progenies and their parents were inoculated with the prevalent races CY28 and CY32 of Puccinia striiformis respectively.The phenotypes of the F1,F2 and BC1 plants were analyzed for resistance to the two races.The results indicated that the resistance in the Dazicao to race CY32 was controlled by one recessive gene,and the resistance to race CY28 by complementary action of one dominant gene and one recessive gene.     

西科麦2028抗条锈性的遗传分析

西科麦2028是地理远缘小麦材料的杂交后代,具有突出的抗条锈病性能。为了解西科麦2028对小麦条锈病的抗性遗传规律,以西科麦2028和铭贤169的杂交群体为研究对象,采用我国目前小麦条锈菌流行小种CYR31、CYR32、CYR33、Su11-4对供试群体进行成株期接种,分析杂交后代的抗病性及分布情况。结果表明:西科麦2028对CYR31的抗病性由3对显性基因控制;对CYR32由2对显性和1对隐性基因控制;对CYR33由1对显性基因控制;对Su11-4由1对显性和1对隐性基因控制。     

非编码的mRNA

非编码的mRNA是近年发现的一类不含典型ORF的mRNA.目前已发现或克隆的这类基因主要有：H19基因,XIST基因,XLSIRT基因,His-1基因,bic基因,rox1和rox2基因等.它们与胚胎发育,肿瘤发生及X染色体失活密切相关.     

白菜CesA基因家族鉴定及表达模式分析

为探究CesA基因家族在白菜生长发育及纤维素合成过程中的作用机制,该文通过生物信息学的方法,以白菜的全基因组序列为研究区域,进行理化特征、基因结构、进化特征、保守基序及结构域、顺式作用元件和组织表达等鉴定分析。结果表明:(1)共鉴定出16个编码纤维素合成酶亚基的CesA基因,该家族成员所编码蛋白的理论等电点为4.76～9.12,相对分子量为17.76～122.67 kD,长度为153～1 089 aa。(2)15个基因不均匀地分布于白菜的7条染色体上,Bra036008定位于scaffold上。(3)大部分成员包含4～14个外显子,1～11个保守基序。(4)该家族具有保守的DDD-QXXRW 保守功能域。(5)该家族编码蛋白主要分布在质膜上,二级结构以无规则卷曲与α-螺旋为主,多数成员都含有CesA蛋白典型的N端、C端和跨膜区。(6)CesA基因在茎中表达量相对较高,其中Bra011865、Bra023952和Bra029874在茎、叶、花中显著表达。该研究结果为后续深入研究CesA基因功能以及白菜生长发育研究奠定了基础。     

橡胶树DELLA蛋白编码基因HbGAI的克隆与表达分析

该研究采用RT-PCR与RACE技术,从橡胶树‘热研7-33-97’胶乳中克隆了1个DELLA蛋白编码基因HbGAI(GenBank登录号为KT696439)。HbGAI全长cDNA序列2 050bp,包含1个长1 842bp的完整开放阅读框。序列分析显示,HbGAI基因编码613个氨基酸,其推导的蛋白含有DELLA和GRAS结构域,分子量为66.476kD,理论等电点为5.19,无跨膜结构域,属于亲水性蛋白。进化树分析表明,HbGAI蛋白与其他植物中DELLA蛋白具有较高的相似性,与麻疯树JcGAI和蓖麻RcGAI亲缘关系较近。荧光定量PCR结果显示,割胶和茉莉酸甲酯处理下调胶乳中HbGAI基因的表达,乙烯利处理4h内显著上调胶乳中HbGAI基因的表达,表明HbGAI基因可能在橡胶树割胶、茉莉酸、乙烯响应中发挥作用。     

不结球白菜BcMPK4基因的分离及表达

为了进一步探讨植物MAPKs(mitogen-activated protein kinases)在植物防卫中的作用,该研究从不结球白菜抗病品种‘苏州青’中克隆到一个抗核盘菌(Sclerotinia sclerotiorum)相关基因,命名为BcMPK4(DDBJ登录号AB557751)。该基因核苷酸序列全长1 334bp,编码373个氨基酸,与已克隆的MPK4基因有不同程度的相似性。系统进化树分析表明,该基因在不同物种之间具有保守性。基因组DNA杂交表明,BcMPK4可能属于一个较小的多基因家族,属组成型表达。实时定量PCR检测表明,核盘菌能够诱导不结球白菜BcMPK4基因的转录表达;BcMPK4基因在不结球白菜叶片中的表达特征说明它可能参与寄主对核盘菌的抗性。     

中国水仙NtAP1基因的克隆与表达分析

采用RT-PCR和RACE技术,从中国水仙(Narcissus tazetta var.chinensis)幼嫩花芽中分离得到1个与花发育相关的MADS-box基因,将其命名为NtAP1(GenBank登录号为JN704304)。该基因全长1 155bp,含有1个762bp的开放阅读框,编码253个氨基酸。系统进化分析表明,该基因属于AP1-like基因。半定量RT-PCR分析表明,该基因在水仙品种‘金盏银台’和‘玉玲珑’的花瓣、副冠、雄蕊和雌蕊中均有表达,且在雌蕊中的表达量最高。研究认为,该实验分离出的NtAP1基因在‘玉玲珑’重瓣的形成过程中没有发挥重要的作用。     

Development of a homologous transformation system for Aspergillus niger based on the pyrG gene

Summary The development of a homologous transformation system for Aspergillus niger is described. The system is based on the use of an orotidine-5-phosphate decarboxylase deficient mutant (pyrG) and a vector, pAB4-1, which contains the functional A. niger pyrG gene as a selection marker. Transformation of the A. niger pyrG mutant with pAB4-1 resulted in the appearance of stable Pyr⁺ transformants at a frequency of 40 transformants per g of DNA. In 90% of these transformants integration had occurred at the resident pyrG locus, resulting either in replacement of the mutant allele by the wild-type allele (60%) or in insertion of one or two copies of the vector (40%). The A. niger pyrG mutant could also be transformed with the vector pDJB2 containing the pyr4 gene of Neurospora crassa, at a frequency of 2 transformants per g of DNA. Integration at the resident pyrG locus was not found with this vector. The vector pAB4-1 is also capable of transforming an Aspergillus nidulans pyrG mutant to Pyr⁺. The pyrG transformation system was used for the introduction of a non-selectable gene into A. niger.     

中国假尾孢属的研究VI.

本文报道中国假尾孢属的16个种,其中有3个新种:藤山柳假尾孢(Pseudocercospora clematoclethrae),仙茅假尾孢(P. curculiginis,),豆付柴假尾孢(P. premnicola), 8个新组合:金粟兰假尾孢(P. chloranthe), 榅桲假尾孢(P. cydoniae),福岗假尾孢(P. fukuokaensis),土连翘假尾孢(P. hymenodictyonis),南五味子假尾孢(P. kadsurae), 野岛假尾孢(P. nojimae).绣线菊假尾孢(P. spiraeicola),球形假尾孢(P. sphaeriiformis)和3个中国新纪录。文中对新种进行了描述并绘图。研究的标本保存在中国科学院微生物研究所真菌标本室(HMAS)。     

In Planta Transformation of Tomato

In this study, in planta transformation of tomato (Solanum lycopersicum L.), using fruit injection and floral dip, is reported. Agrobacterium tumefaciens strain EHA 105 containing one of three constructs, i.e., pROKIIAP1GUSint (carrying the Apetala 1 [AP1] gene), pROKIILFYGUSint (carrying the LEAFY [LFY] gene), or p35SGUSint (carrying the β-glucuronidase [GUS] gene), was used for plant transformation. For fruit injection transformation, no significant effects (p > 0.05) of the construct used were observed. The highest frequency of transformation was obtained following 48-h incubation of tomato fruit with bacterial cells harboring either one of the three constructs; transformation frequencies of 17%, 19%, and 21% for AP1, LFY, and GUS gene constructs, respectively, were obtained. When fruit maturity was evaluated in fruit injection experiments, mature red fruit resulted in higher frequency of transformants than immature green fruit with 40%, 35%, and 42% for AP1, LFY, and GUS gene constructs, respectively. For floral dip transformation, a higher number of transformants was obtained when the GUS gene construct was used instead of either the AP1 or LFY gene construct, thus suggesting a possible inhibitory effect of the flowering genes used. When flowers were transformed prior to rather than following pollination, they yielded a higher transformation frequency, 12% for the LFY construct and 23% for the GUS construct (p < 0.05), although no transformant was obtained with the AP1 gene construct. All putative GUS-positive transformants were analyzed using polymerase chain reaction and confirmed for the presence of the transgene. Compared to control plants, transgenic plants carrying either the AP1 or LFY transgene flowered earlier and showed several different morphological characters.     

Osmoregulation in the model organismEscherichia coli: genes governing the synthesis of glycine betaine and trehalose and their use in metabolic engineering of stress tolerance

Glycine betaine is known to be the preferred osmoprotectant in many bacteria, and glycine betaine accumulation has also been correlated with increased cold tolerance. Trehalose is often a minor osmoprotectant in bacteria and it is a major determinant for desiccation tolerance in many so-called anhydrobiotic organisms such as baker's yeast(Saccharomyces cerevisiae). Escherichia coli has two pathways for synthesis of these protective molecules; i.e., a two-step conversion of UDP-glucose and glucose-6-phosphate to trehalose and a two-step oxidation of externally-supplied choline to glycine betaine. The genes governing the choline-to-glycine betaine pathway have been studied inE. coli and several other bacteria and higher plants. The genes governing UDP-glucose-dependent trehalose synthesis have been studied inE. coli andS. cerevisiae. Because of their well-documented function in stress protection, glycine betaine and trehalose have been identified as targets for metabolic engineering of stress tolerance. Examples of this experimental approach include the expression of theE. coli betA andArthrobacter globiformis codA genes for glycine betaine synthesis in plants and distantly related bacteria, and the expression of theE. coli otsA and yeastTPS1 genes for trehalose synthesis in plants. The published data show that glycine betaine synthesis protects transgenic plants and phototrophic bacteria against stress caused by salt and cold. Trehalose synthesis has been reported to confer increased drought tolerance in transgenic plants, but it causes negative side effects which is of concern. Thus, the much-used model organismE. coli has now become a gene resource for metabolic engineering of stress tolerance.