青鱼■和三角鲂不同亚科之间的杂交研究——Ⅱ、青鱼(?)、三角鲂(?)及其子一代乳酸脱氢酶同工酶的比较研究

本文是从生化遗传学的角度来研究青鱼■与三角鲂■杂交所产生的子一代中存在两种性状个体的机理。用聚丙烯酰胺凝胶盘状电泳和CS_(910)双波长扫描仪,研究青鱼、三角鲂及其子一代七种组织的乳酸脱氢酶(LDH)同工酶谱。实验表明:青鱼、三角鲂及其子一代各组织的LDH同工酶存在着组织的特异性,亲本之间LDH同工酶谱存在着很大的差异,为两种不同的谱型;子一代中具有母本青鱼性状的青鱼型个体,其LDH同工酶谱型与母本青鱼基本相同;而子一代兼有父母双亲性状的中间型个体,其LDH同工酶谱比青鱼型个体明显增加,类似父本。根据以往细胞遗传学、形态解剖学(拟另文发表)以及本实验的研究,可以断定具有中间型特征的鱼是真正的杂种,其LDH同工酶父本呈显性,而与母本青鱼相似的青鱼型鱼,可能是由青鱼卵子行雌核发育而来。     

Evolutionary and ecological consequences of interspecific hybridization in cladocerans

The evolutionary process of interspecific hybridization in cladocerans is reviewed based on ecological and population genetic data. The evolutionary consequences of hybridization, biogeographic patterns and fitness comparisons are analyzed within the conceptual framework of theories on hybridization. Among species of theD. longispina complex no interpopulational transition zones (hybrid zones) have been detected, but rather patchy distributions of hybrids and parentals have been found. Hybrids occur across broad geographic ranges and can be more abundant than parental species. Due to asexual reproduction (ameiotic parthenogenesis), hybrid breakdown can be avoided, and hybrids can even (temporarily) combine advantageous traits of both parental species. Evolutionary consequences may arise from repeated backcrossing, which in some cases results in introgression and patterns of reticulate evolution.Those forms which possess in some considerable degree the character of species, but which are so closely similar to some other forms, or are so closely linked to them by intermediate gradations, that naturalists do not like to rank them as distinct species, are in several respects the most important to us (Charles Robert Darwin 1859)     

牛酪蛋白cDNA基因克隆的改建

牛酪蛋白全长cDNA克隆pB_aS_1C184经Bgl Ⅰ和EcoR Ⅰ双酶切,回收其中的酪蛋白基因编码片段,与经BamH Ⅰ、SmaⅠ双酶切的植物表达载体pBI121.2分两步连接:第一步载体的BamHⅠ末端与酪蛋白基因的BglⅠ粘性末端连接;第二步用T_4DNA多聚酶补平酪蛋白基因的EcoR Ⅰ末端,再与载体SmaⅠ进行平末端连接而环化,转化JM109菌株,从得到的33个转化子中,通过~(32)P标记的酪蛋白cDNA基因为探针,点杂交筛选到一个阳性克隆。经酶切鉴定,确认酪蛋白cDNA基因编码区已正确插入到pBI121.2中。     

国兰杂交育种研究概况

对国产兰属植物中的春兰、蕙兰、建兰、墨兰、寒兰以及莲瓣兰的杂交育种情况进行了综述,并对地生兰在兰属植物新品种培育中的应用提出了设想,以期对兰属植物花卉新品种开发提供参考。     

纳米金在DNA电化学传感器中的应用研究

利用自组装单分子膜原理,通过层层组装的方法将金纳米粒子(AuNPs)和DNA探针分别固定到金电极表面制备成探针电极。结果表明纳米金可以使响应电流大大增强,有利于提高检测的灵敏度;同时DNA自组装到纳米金修饰的金电极上,形成一层致密的分子膜,可使响应电流下降。     

分子生物学技术在水产养殖动物细菌性病原检测中的应用

回顾了核酸杂交、基因芯片、PCR等分子生物学技术在水产养殖动物细菌性病原检测中的应用,并对水产养殖细菌性疾病诊断技术的发展方向作了展望。     

胡萝卜与川西獐牙菜不对称体细胞杂交

川西獐牙菜(Swertia musstii Franch)原生质体经260μw／cm^2紫外线照射30s、1min、2min、3rain后，与胡萝卜(Daucus carota L.var.sative DC)原生质体在PEG诱导下融合．融合再生的110个单细胞克隆形态学、染色体、同功酶分析表明，35个含有酯酶及／或过氧化物酶同工酶的双亲特征带，部分杂种产生新带，染色体数目多为16-18，确证它们为体细胞杂种．     

基于细胞色素b基因研究两种石鸡的渐渗杂交

大石鸡是我国特有种,分布区狭窄;石鸡为广布种;两者都是我国北方干旱、半干旱荒漠环境的指示鸟类。利用线粒体DNA细胞色素b基因标记分析了大石鸡106个、石鸡48个样品,获得大石鸡单倍型9个,石鸡单倍型13个;在大石鸡种群中发现8个个体呈现石鸡基因模式（Hap-1和Hap-2）,但是在石鸡种群中没有发现大石鸡的基因模式,确认为石鸡和大石鸡之间的渐渗杂交;确认杂交带从六盘山脉向南到陇南地区的礼县一带,杂交带长度为400km,宽度为130km。结果表明目前渐渗杂交对大石鸡种群遗传多样性影响不大,在不长的进化时期内,对增加物种多样性是有好处的。建议进行长期野外监测,以便弄清发生渐渗杂交的野外生态学数据,为物种进化研究提供参考依据。     

Localization and expression of TR3 orphan receptor protein and its mRNA in rat

The cellular localization and specific expression of TR3 mRNA in rat testis were investigated by the method of immuno- histochemistry andin situ hybridization. It was demonstrated that orphan receptor TR3 was expressed in a significant amount in rat testis and TR3 protein and mRNA were specifically localized in germ cells, suggesting that TR3 may have an important function in regulating rat germ cell development.