番茄复三螺旋基因响应外源激素和非生物胁迫的研究

复三螺旋(double trihelix)基因在植物形态建成和植株抗逆性方面发挥关键作用。该研究以番茄自交品种AC⁺⁺为试验材料,运用生物信息学方法与qRT PCR技术对5个复三螺旋成员(SlGTL1~SlGTL5)在番茄体内不同器官的表达模式、以及基因对激素与非生物胁迫的响应进行表达分析,以探讨番茄复三螺旋基因的功能。结果表明：(1)生物信息学分析显示,番茄中含有5个复三螺旋基因(SlGTL1~SlGTL5);进化树分析表明,番茄复三螺旋基因具有物种特异性。(2)qRT PCR分析显示,番茄SlGTL3基因在根和茎中特异表达,其他4个基因均在果实中较高表达,表明不同番茄复三螺旋基因的表达具有组织特异性。(3)激素诱导表达结果显示,SlGTL1只响应ABA(1种)激素,而SlGTL5基因可响应4种激素,且速度较快。(4)非生物胁迫诱导证实,SlGTL3、SlGTL5基因可响应盐胁迫,SlGTL3~SlGTL5基因可响应极端温度,SlGTL3和SlGTL4基因可响应机械损伤;SlGTL1、SlGTL4和SlGTL5可响应脱水胁迫。研究认为,SlGTL3的功能可能与植株形态建成和非生物胁迫有关,其他4个基因的功能可能与果实的发育有关;推测SlGTL1可能与ABA信号途径有关,SlGTL5快速响应多种激素,可能位于信息传递的节点,其功能可能与信号传递有关。     

饲料中转基因成分对家蚕生长发育的影响

采用家蚕（Bombyx mori）H9品种作为实验动物,分别用转基因和非转基因大豆粉制作的人工饲料进行饲育。通过饲育试验,比较分析了不同处理后家蚕的龄期经过时间、全茧量、茧层量、茧层率、蛹体重、疏毛率、死亡率、每龄眠起体重等经济性状指标。同时采用PCR方法对转基因饲料饲育后家蚕组织中外源基因的表达情况进行了检测。结果显示,含转基因大豆粉的人工饲料对家蚕的生长发育并无显著影响,且不存在外源基因的污染。     

Mapping QTLs for seed yield and drought susceptibility index in soy-bean（Glycine max L.） across different environments

Drought stress has long been a major constraint in maintaining yield stability of soybean （Glycine max （L.） Merr.） in rainfed ecosystems. The identification of consistent quantitative trait loci （QTL） involving seed yield per plant （YP） and drought susceptibility index （DSI） in a population across different environments would therefore be important in molecular marker-assisted breeding of soybean cultivars suitable for rainfed regions. The YP of a recombinant line population of 184 F2：7：11 lines from a cross of Kefengl and Nannong1138-2 was studied under water-stressed （WS） and well-watered （WW） conditions in field （F） and greenhouse （G） trials, and DSI for yield was calculated in two trials. Nineteen QTLs associated with YP-WS and YP-WW, and 10 QTLs associated with DSI, were identi- fied. Comparison of these QTL locations with previous findings showed that the majority of these regions control one or more traits re- lated to yield and other agronomic traits. One QTL on molecular linkage group （MLG） K for YP-F, and two QTLs on MLG C2 for YP-G, remained constant across different water regimes. The regions on MLG C2 for YP-WW-F and MLG H for YP-WS-F had a pleiotropic effect on DSI-F, and MLG A1 for YP-WS-G had a pleiotropic effect on DSI-G. The identification of consistent QTLs for YP and DSI across different environments will significantly improve the efficiency of selecting for drought tolerance in soybean.     

中国不同年代食品动物大肠杆菌耐药性调查研究

收集到20世纪70,80,90年代和2000年食品动物大肠杆菌共326株,对不同年代的大肠杆菌进行耐药性、整合子／基因盒测定,结果表明在过去的30多年里,食品动物大肠杆菌耐药性呈逐渐增长的趋势．从1970～2000年,对青霉素类的耐药率从19．0％增长到81．3％;对四环素类药的耐药率从61．9％～63．5％增长到89．5％～93．1％;对氨基糖甙类的耐药率从0-9．5％增长到5．0％～63．1％,对氟喹诺酮类的耐药率从0％增长到50.2％-53．0％;对磺胺类药的耐药率从11．7％～57．1％增长到77．7％～79．7％;对氯霉素的耐药率从39．7％增长到51．8％．整合子的携带率从20世纪70年代的17．5％增长到2000年的79．1％,其中大多数为I型整合子,也有少数Ⅱ型整合子（90年代为4．4％,2000年为11．8％）．在20世纪70和80年代,大多数I型整合子的基因盒编码aadAI基因,比例分别为72．7％和70．0％．20世纪90年代和2000年基因编码dfrA—aadA的占多数,分别为80．0％和74．7％．近4个世纪以来,细菌的多重耐药谱也逐渐增宽．本项研究给兽医从业者滥用抗菌药提出了警示,同时提出中国动物源细菌耐药性的监测和控制是必要的．     

运用分子生物学技术监测水环境中产毒蓝藻

有毒蓝藻在形成水华破坏水体环境的同时,也对人畜产生危害。运用分子生物学技术对水环境中产毒蓝藻进行监测,由于其简单、快速和经济等优点,逐渐成为各国学者关注的热点。本文从以下3个方面对其进行了综述:1)早期分子生物学技术在产毒蓝藻诊断中的运用;2)以产毒基因为靶标进行的产毒蓝藻诊断;3)运用基因芯片技术对产毒蓝藻进行检测。与传统的分子生物学技术相比,生物芯片技术具有体积小、重量轻、便于携带、分析自动快速、高通量等许多传统方法所不能比拟的优势。因此,该技术在蓝藻毒素检测中的运用必将给目前的产毒蓝藻的检测带来一场新的革命。     

蜘蛛拖牵丝蛋白基因的克隆与表达

蜘蛛丝具有极高的强度和韧度,工业和医学应用价值很高,但由于蜘蛛的不可驯养性使其应用受到限制.因此,本文尝试利用基因工程的方法获得蛛丝蛋白的表达.我们利用巢式PCR技术从大腹圆蛛Araneus ventricosus基因组中克隆了长度为837 bp的拖牵丝蛋白基因(ASP),并分别将其构建至原核表达载体pGEX-6p-1和真核表达载体pGFP-N2上,分别命名为pASG和pASN.pASG在大肠杆菌中16℃下24 h诱导表达后,经蛋白质印迹证明成功地表达了GST-ASP融合蛋白;pASN转染昆虫sf9细胞48 h后观察到了绿色荧光蛋白GFP的表达,表明ASP基因在大肠杆菌和真核细胞中分别得到了正确表达.本研究为利用基因工程的方法开发蛛丝蛋白的生产途径提供了有益的尝试.     

Panicle Water Potential, a Physiological Trait to Identify Drought Tolerance in Rice

Two upland rice varieties （IRAT109, IAPAR9） and one lowland rice variety （Zhenshan 97B） were planted in summer and treated with both normal （full water） and drought stress in the reproductive stage. Panicle water potential （PWP） and leaf water potential （LWP） were measured every 1.0-1.5 h over 24 h on sunny days. Both PWP and LWP of upland varieties started to decrease later, maintained a higher level and recovered more quickly than that of the lowland variety. The results show that PWP can be used as an indicator of plant water status based on the parallel daily changes, and the high correlation between PWP and LWP. Similar correlations were also observed between PWP, LWP and eight traits related to plant growth and grain yield formation. PWP seemed to be more effective for distinguishing the upland rice varieties with different drought-tolerant ability. Differences in PWP and LWP between upland and lowland rice varieties were also observed at noon even under normal water conditions, implying the incorporation of the drought-tolerant mechanism to improve the photosynthesis and yield of traditional paddy rice.     

蚕豆主要数量性状的遗传主成份和数量分类

对50个蚕豆品种的7个数量性状进行了遗传主成份分析, 初步提出了评选蚕豆品种的遗传主成份标准,并筛选出18个综合性状优良的亲本品种。测定了50个蚕豆品种的遗传距离, 根据遗传距离大小,将50个蚕豆品种聚类为2群、 3类、9组。分类结果指出,蚕豆品种的遗传距离大小与地理差异有些似有一定关系,但在总体上,二者间无必然联系。 Abastract:Analysis of major Genetic component analysis was performed for 7 quantitative characters of 50 faba bean lines and according to the analysis,18 lines were selected as parents.The 50 lines were classified into 2 subpopulations,3 types and 9 groups according to their genetic distance.The results showed that there was seemly a correlation between geographical distribution and genetic distance,nevertheless most lines within the same cluster were close in genetic distance but far in geographic sites.