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81.
对比考察了农垦58s与7001s、8902s与培矮64s及8902s与安农S1等3个光(温)敏核不育水稻杂交组合的双亲、F1、B1、B2和F2世代的样本及每一个体的PE和TE的变异。无论双亲核不育基因的等位程度及栽培环境的光、温周期如何,在多数情况下都显示了如下的规律:(1)后代样本PE、TE的大小虽然形形色色,但都取决于其双亲。F1表示完全显性甚至超显性。(2)F2个体的PE或TE、尤其同一个体PE与TE的集成类型发生有规律的分离和超亲分离,产生形形色色的育性转换类型。在纯粹由雄性不育个体组成的F2不育分样本中也发生同样分离。(3)PE或TE的广义遗传力的估值都大于50%。据此推断PE、TE是两个可遗传并可供选择的独立性状;并对育性转换现象的遗传机制也进行了讨论。  相似文献   
82.
以基因枪介导获转ps1—barnase基因的工程雄性不育水稻植株   总被引:17,自引:0,他引:17  
凌定厚 Zhang  SP 《遗传学报》1998,25(5):433-442
以ps1-barnase(brn)为目的基因,pHcintG(PG)为选择/标记基因进行共转化,以PDS-1000-氦气基因枪介导,将brn及PG基因转化到水稻台北309及秋光的核DNA中,得到了转ps1-barnase基因的工程雄性不育植株。以悬浮细胞作为基因枪轰击的靶材料,转化植株再生频率较初级愈伤组织的为高。转brn基因植株的其他主要性状与供体亲本无显著差异,但却表现不育。其不育的程度在不同的植株之间表现不同。在转brn基因植株中观察到全不育(占全部brn阳性植株的40.6%)、高不育(占15.6%)及半不育的个体(占43.7%)。全不育的转基因植株自交完全不能结实(结实率为零),除个别植株外,花粉完全不被I-KI染色;而人工授以正常的花粉则可以获得杂交种子。而brn基因的阴性植株及未进行转化的对照植株则完全可育,表明转基因植株之雄性不育乃brn基因所致。结果表明,brn基因在水稻中是完全可以正常表达的,其表达的时期推测在花粉母细胞减数分裂前至花粉形成之间的整个时期。  相似文献   
83.
表达barstar基因及bar基因的转基因油菜的研究   总被引:30,自引:0,他引:30  
从细菌Bacilusamyloliquefaciens染色体DNA中克隆了barnase抑制剂barstar的基因,构建了带有TA-29基因5′调控区(-1300-+3)与barstar基因编码区、CaMV35S启动子与除草剂抗性基因bar两个表达框架的植物表达质粒pBBS。以“双低”油菜“5-4”的子叶柄为受体,通过农杆菌介导的遗传转化,获得了在含有10mg/L卡那霉素和20mg/LPPT的筛选培养基上再生的转基因植株。PCR分析结果表明,barstar基因已整合到油菜染色体上;Northernblot检测表明,barstar基因及bar基因在转基因植物中得到了正确的调控与表达。以转基因油菜“5-4”为父本授粉给表达barnase基因的雄性不育植株,不育株能正常结实。  相似文献   
84.
转基因植物生产动物疫苗的研究及应用   总被引:6,自引:0,他引:6  
转基因植物生产动物疫苗的研究及应用范国昌1,2山松1钱凯先2沈桂芳1(1.中国农业科学院生物技术研究中心,北京100081)(2.浙江大学生物科学与技术系,杭州310027)ResearchandApplicationonTransgenicPlan...  相似文献   
85.
哺乳动物的核移植陆长富卢光(湖南医科大学人类生殖工程研究室,长沙410078)NuclearTransplantationinMammalianLUChangfuLUGuangxiu(HumanReproductiveEngineringLabor...  相似文献   
86.
以油菜细胞质雄性不育系1193A和恢复系1193R2为亲本构建F2分离群体,并运用BSA法构建了可育和不育基因池。利用1521对SSR引物进行了多态性分析,结果表明有36对引物在亲本和基因池间都表现多态性,用F2单株验证表明有11对引物与恢复基因连锁,离恢复基因较近的2个标记CB10316和Bn GMS171分布在恢复基因Rf的两侧,遗传距离分别为3.9 c M和5.7 c M,可作为恢复系标记辅助育种的候选标记。  相似文献   
87.
Males of the orb‐weaving spider species Argiope bruennichi (Araneidae) are frequently victims of sexual cannibalism. Therefore, a male spider approaching a female should have strategies to avoid being killed before copulation. Our present field study detected six types of A. bruennichi male positions vis‐à‐vis the female web. In 78% of situations (39/50), only one male attached to a female. Two males attached to the same female in 11 cases. We observed no cases of three or more males on the same female web. We most commonly observed the situation of a male staying in its own web and connecting to a female's web with its silk thread (46% of cases). Of the female webs chosen by males, 68% were decorated with both an upper and lower portion of stabilimentum – a conspicuous white silk structure that reflects much more ultraviolet light than other spider silks in the web. Only 14% (7/50) of the selected webs lacked stabilimentum. Therefore, we conducted an experiment to investigate the males' choice between females' webs with and without stabilimentum. Of the 24 males used in the experiment, 10 chose webs with stabilimentum. This result did not show a strong preference of the male for stabilimentum between equally sized webs, and thus did not support an earlier suggestion that stabilimentum in A. bruennichi might function to guide males to females for mating.  相似文献   
88.
89.
The mangrove rivulus Kryptolebias marmoratus a small cyprinodont fish native to tropical and subtropical waters from Florida to Brazil, is one of two known self-fertilizing, hermaphroditic vertebrates of which K. marmoratus displays androdioecy, a complex system of reproduction in which hermaphrodites and males are present. This study describes the behavioral repertoires observed during dyadic interactions in the laboratory. Kryptolebias marmoratus exhibited 23 distinctive acts or behaviors. Acts were divided into four categories: aggressive, submissive, neutral, and reproductive. Leading and following behaviors played important roles in the behavioral repertoires of these fish. In hermaphrodite-male dyads, males exclusively initiated the reproductive process and actively pursued hermaphrodites. When hermaphrodites were paired, there was no evidence that they behaved like other simultaneous hermaphrodites that alternate sexual roles (e.g. serranids). Hermaphrodites were extremely aggressive towards one another, and the aggressor established dominance rapidly. Male-male dyads were divided into two subdivisions based on the presence or absence of the caudal ocellus on one fish. A caudal ocellus on one male appeared to signal the possibility of a potential mating partner to males lacking it. Pairings of males without an ocellus were similar to hermaphrodite-hermaphrodite dyads in that both members of the pair were aggressive towards one another. These observations may be indicative of interactions taking place in natural communities or assemblages of fish in which both males and hermaphrodites occur and provide evidence on the role of dyadic interactions in the mixed-mating strategies [Current Zoology 56 (1): 6-17, 2010].  相似文献   
90.
Wael A. Salameh 《Steroids》2010,75(2):169-175
Accurate measurement of testosterone concentration is of critical importance when diagnosing and treating male hypogonadism, congenital adrenal hyperplasia, premature or delayed puberty, and androgen excess in polycystic ovary syndrome or other virilizing conditions. However, some assays have inherent limitations and biases that affect measurement of low-testosterone values. Therefore, we developed a highly specific online mass spectrometry method. Sera were extracted online using high-turbulence flow liquid chromatography coupled to analytical HPLC and atmospheric pressure chemical ionization tandem mass spectrometry (HTLC-APCI-MS/MS). Analyte ions were monitored by multiple reaction monitoring (MRM). Total analysis time was 1.15 min per sample when using the multiplexing system. Testosterone concentrations were measured directly from 150 μL of serum or plasma without derivatization or liquid-liquid extraction. The lower limit of quantification was 0.3 ng/dL, and the assay was linear up to 2000 ng/dL. The method compared very well with an established RIA: y = 1.02x + 1.5, r2 = 0.994. Comparison with a platform immunoassay confirmed the previously reported ICMA positive bias at low concentrations. Male and female adult and pediatric reference ranges were developed for this very sensitive and accurate high-throughput LC-MS/MS method. This method is suitable for measuring the expected low-testosterone concentrations seen in women, children, and hypogonadal males and for monitoring testosterone suppressive therapy in prostate cancer patients.  相似文献   
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