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。     

pH值对Gigaspora margarita孢子萌发、菌丝生长与聚磷酸盐含量的影响

土壤pH值是影响AM真菌的生理与生态过程的重要因子之一,本试验在培养基上接种Gigasporamargarita的孢子,研究了pH值分别为5.2、6.0和6.8时孢子萌发率、菌丝生长和菌丝中聚磷酸盐(polyP)的含量。结果表明,不同pH条件下的孢子萌发率没有明显差异,培养12d后的萌发率为70%左右;随着pH的升高,菌丝的长度逐渐增加,表明低pH对菌丝的生长有一定的抑制效应;培养12d后,孢子中polyP含量低于菌丝中polyP含量,pH6.0和pH6.8的条件下菌丝中polyP含量明显高于pH5.2的含量,表明低pH也能降低菌丝中的聚磷酸盐含量。认为低pH对菌丝生长和polyP含量的抑制可能是其限制AM真菌功能发挥的重要机制之一。     

Isolation and cultivation of murine hematopoietic stem cells and expression of hFIX mediated by recombinant Ientiviral vectors in vitro

Hematopoietic stem cells(HSCs)are an attractive target for gene therapy,especially for inherited blood diseases.Moreover,recombinant lentiviral vectors are considered to be prospective in HSCs gene therapy for the high efficiency of infection.In this study,murine mononuclear cells(MNCs)were isolated from bone marrow and cultured in suspension.and then Lin-CDll7+HSCs were isolated by immunomagnetic beads.During culturing,cells and colonies increased in HSCS supplied with cytokines while no change was observed in the control group without cytokines.FUXW recombinant lentiviral vectors were produced by calcium phosphate-mediated transient cotransfection infected MNCs from ICR and C57 mice.The hFIX expressions were 41.7±4.2 ng/mL and 34.5±6.6 ng/mL in supematant on 7d.The hFIX expressions of HSCs infected by FUXW recombinant lentiviral vectors were 46.6±5.7 ng/mL(with cytokines)and 33.3±4.8 ng/mL(without cytokines)in supernatant on 7d.Results indicate that recombinant lentiviral vectors can infect murine MNCs and Lin-CD117+HSCs efficiently,and expression of the transgene can be improved when supplied with cytokines.     

Polymorphic microsatellite markers in the Zhikong scallop Chlamys farreri

The colony hybridization method was presented for isolating microsatellite markers in Zhikong scallop, Chlamys farreri. We designed primers to amplify 26 unique microsatellites. Fourteen primer pairs amplified clearly and were polymorphic. Based on characterization with 60 unrelated individuals, the number of alleles ranges from two to 13, and the expected heterozygosity ranges from 0.22 to 0.91. These markers have the potential for genetic studies in population structure and intraspecific variation.     

Isolation and characterization of a set of microsatellite loci in the submerged macrophyte,Vallisneria spinulosa Yan (Hydrocharitaceae)

Twenty‐six microsatellites were isolated and characterized from an AAG‐enriched genomic library of Vallisneria spinulosa, a dominant submerged macrophyte in the middle‐lower reaches of the Yangtze River. Microsatellite polymorphism was evaluated in a random population and 11 microsatellite loci were found polymorphic with 2–18 alleles per locus and observed heterozygosity ranging from 0.281 to 1.000. These polymorphic markers were expected to be valuable for population genetic and demographic analyses of V. spinulosa.     

组织因子对肝癌细胞侵袭能力的影响

组织因子（Tissue Factor,TF）是机体外源性凝血途径的启动因子,发挥生理性止血的重要作用.近来研究表明,TF除凝血功能外尚与多种恶性肿瘤的血管生成,侵袭转移及预后密切相关.为了探讨TF对人类肝癌细胞的影响,将成功构建带有正义/反义TF cDNA的真核细胞表达质粒pcDNA3.1-TF(+)/(-)转染人肝癌细胞系HepG2,经药物筛选后获得稳定细胞克隆;应用RT-PCR和Western blot检测内源性TF mRNA及蛋白质表达水平的变化;通过体外侵袭实验进一步分析对细胞侵袭能力所造成的影响.结果显示,转染pcDNA3.1-TF(+)质粒的细胞TF表达水平明显升高,相应的其侵袭能力明显增强,而转染pcDNA3.1-TF(-)质粒的细胞TF表达水平,及体外侵袭能力显著下降.研究结果表明,TF可以增强人类肝癌细胞体外侵袭和转移能力,与肝癌的进展相关,可作为原发性肝癌治疗的一个新靶点进行研究.     

野生植物蒲公英营养成分的研究

对野生植物蒲公英的营养成分进行了分析,结果表明,蒲公英中含有多种营养成分,丰富的矿质元素和维生素及其β-胡萝卜素。蒲公英中至少含有17种氨基酸。蒲公英营养成分分析旨在为开发利用植物资源提供科学依据。     

木聚糖酶XYNB的N46D突变、表达及酶学性质变化

对来源于Streptomyces olivaceoviridis的高比活木聚糖酶XYNB进行同源建模和同源序列比较,发现第11族木聚糖酶的催化结构域在β折叠股A3和B3之间存的一个保守的氨基酸位点,该位点与木聚糖酶的pH特性有关.据此设计了XYNB的N46D定点突变.将突变酶XYNBN46D在毕赤酵母中表达,表达的XYNBN46D经纯化后与原酶XYNB(同样经毕赤酵母表达后纯化)进行酶学性质比较,结果表明, XYNBN46D的最适pH值由5.2下降到4.2,pH稳定性也向酸性pH偏移,同时,热稳定性和最适温度也有一定的提高, 但酶的比活性显著下降.结果证实,木聚糖酶XYNB的第46位Asn与其最适pH值相关.对导致酶学性质改变的可能因素进行了分析,结果为进一步的结构与功能研究提供了资料.     

野生越南槐组织特异性内生真菌组及体外抗病原菌功能

有益微生物组能帮助宿主植物防御病害。越南槐的根、茎和种子在野外环境下健康发芽生长,而栽培越南槐各组织极易感病。为了探明利用野生越南槐有益内生真菌组防治宿主病害的可能,该文在分离健康野生越南槐根、茎和种子内生真菌的基础上,并结合形态学和ITS序列特征鉴定内生真菌,通过系统发育树、α-多样性指数和β-多样性指数分别分析各内生真菌组的系统进化、多样性和相似性,通过琼脂块法和平板对峙法测试内生真菌组的体外抗病原菌功能。结果表明:(1)从越南槐根、茎和种子内生真菌组分别分离鉴定131株23个分类单元、108株23个分类单元、64株11个分类单元;(2)特有属多且所有种均为特有种显示根、茎和种子内生真菌组在属种进化上具有组织特异性;(3)根-茎/根-种子/茎-种子间极低的β-多样性显示根、茎和种子各内生真菌组间的物种相似性极低;(4)高的α-多样性显示越南槐根、茎和种子均有丰富多样的内生真菌组;(5)各内生真菌组三分之一以上的分类单元在体外均能拮抗供试病原菌,根茎内生真菌组显示了强广谱的体外抗病原细/真菌功能,种子内生真菌组显示了强广谱的体外抗病原真菌功能。该研究结果表明健康野生越南槐根、茎和种子内部均存在有益内生真菌组,其具有生物多样性、组织特异性以及强广谱的体外抗病原菌功能,在宿主各组织的抗病性方面可能发挥重要作用。这些结果将为进一步利用有益真菌组防治栽培越南槐各组织病害提供了材料和实验基础。     

乳酸菌肽聚糖部分免疫增强作用的研究

以小鼠为实验材料研究了肽聚糖部分免疫学活性,结果表明:小鼠腹腔注射肽聚糖后,相比对照组而言, Z8、Z17肽聚糖组巨噬细胞(MΦ)吞噬率、吞噬指数都明显提高,血清溶菌酶活性显著增强,统计学分析差异极显著(P＜0．01)。肽聚糖对鸡新城疫疫苗免疫增强效果的观察表明,与对照组相比,Z8、Z17肽聚糖组能明显提高新城疫抗体水平,并使抗体高峰水平维持时间延长。同时动物实验也表明,两个肽聚糖组间活性差异不显著,没有特异性。