Phylogentic Relationships of Living Amphibians Among Three Orders Based on the Mitochondrial tRNA Genes

现存两栖类 3个目的系统发生关系仍然没有统一意见 ,最广泛被接受的假说是单系起源 ,并且无尾类和有尾类为姐妹群关系而排斥蚓螈类 (蛙类假说 )。然而 ,这一假说一直存在争议。我们在测定了泽蛙线粒体基因组全序列的基础上 ,与已知其他的 6种两栖类进行详细的比较分析 ,同时选择了 11种高等脊椎动物的线粒体全基因序列 ,以硬骨鱼类作外群 ,用 2 2个tRNA基因合并数据进行系统发生重建分析 ,结果表明MP、ML树都强力地支持现生两栖类动物为单系群 ,并且有尾目和蚓螈目为姐妹群关系。这个结果与蛙类假说是相矛盾的 ,与Bolt (1991)在形态学基础上提出的有尾类和蚓螈类为姐妹群关系的假说相一致 ,并得到建立在线粒体和核rRNA基因数据基础上的许多分子研究的支持。另外还探讨了本结果与前人的研究不一致的原因 ,以及利用线粒体全基因序列进行系统发生分析可能存在的偏差To date,there still is lack of a general consensus regarding the phylogenetic relationships of three living orders of amphibian among herpetologists.The most widely accepted hypothesis is the monophyletic origin in the class Amphibia,which proposed a sister-group relationship between Caudata and Anura (the Batrachia hypothesis) to the exclusion of the Gymnophiona.However,the phylogenetic relationship among living amphibians is still a controversial issue.The complete nucleotide sequence of the mitochondrial genome of Fejervarya limnocharis was detailedly compared with those of 6 other amphibians.The nucleotide sequences of 22 tRNA encoded by 7 amphibians mitochondrial genomes were combined and aligned to the homologous sequences of the 11 veterbrate taxa.Teleosts selected as outgroup,the phylogenetic analyses results show that MP and ML trees all strongly support the monophyly of living amphibians with respect to other living tetrapods and favor a sister group relationship for caecilians and urodeles.Robustness of our results was confirmed by high bootstrap support of all nodes in the trees.This result contradicts the Batrachia hypothesis,and is consistent with Bolt's hypothesis (1991) basing on the morphological data.The result was also supported by previous molecular studies based on the data from mitochondrial and nuclear rRNA genes.In addition,the reason for our result inconsistent with previous works and the shortcomings of phylogenetic analyses based on the complete mitochondrial genomes were also discussed.教育部骨干教师资助计划项目 (GG -180 -2 10 0 2 40 3 -1740 );; 教育部留学回国人员启动基金资助~

Phylogenetic Relationships of Cervinae Based on Sequence of Mitochondrial Cytochrome b Gene

鹿亚科共有 4个属 ,各属间和属内特别是鹿属内的系统进化关系存在疑义。根据Cytb基因序列分析 ,探讨了鹿亚科及中国鹿属、马鹿亚种的进化关系。结果分析表明 :现行分类系统中 ,斑鹿属可能并非单系发生 ,暗示应将豚鹿并入鹿属 ;麋鹿属与鹿属有较近的进化关系 ,也应并入鹿属 ;鹿属的进化地位有待进一步研究 ;归并后的鹿属为单系发生。中国马鹿各亚种在系统发生上是一单系群 ,其中马鹿天山亚种和阿尔泰亚种聚为最原始的一支。The phylogenetic relationships among and within genera Dama,Axis,Elaphurus ,and Cervus in subfamily Cervinae remain controversial,particularly within genus Cervus .We analyzed the sequence of Cyt b gene of the genera,5 species of Cervus ,and 6 subspecies of C elaphus distributing in China.The results suggest that:Genus Axis might not be monophyletic and A porcinus should be merged into Cervus .A close genetic relationship between Elaphurus and Cervus indicated that two taxa should be incorporated into the same genus,whereas the classification status of Dama dama still remained uncertain. Cervus ,including Père Davids deer and hog deer,comprised a monophyletic clade.Subspecies of Chinas C elaphus ,which derived from C nippon ,formed a monophyletic group.Among them, C e songaricus and C e sibiricus clustered together and diverged early.国家自然科学基金资助项目 (3 9870 913 ) ;; 国家教育部骨干教师资助计划项目 ;; 江苏省“3 3 3工程”人才培养基金资

TS-1分子筛催化苯乙酮氨肟化反应

研究了钛硅分子筛(TS-1)催化苯乙酮氨肟化反应中溶剂、反应温度、助催化剂(氧化铝和乙酸铵)、氨水及H2O2用量对反应的影响.结果表明,适宜的溶剂为乙醇,最佳反应温度为80℃,助催化剂乙酸铵在溶液中的浓度不低于0.43%(ω)时能显著提高苯乙酮氨肟反应的转化率,而Al2O3的作用不明显.为了获得较高的转化率,物料中NH3/苯乙酮以及H2O2/苯乙酮的摩尔比应分别控制在2.00和1.27以上

TS-1分子筛催化苯乙酮氨肟化反应

研究了钛硅分子筛(TS-1)催化苯乙酮氨肟化反应中溶剂、反应温度、助催化剂(氧化铝和乙酸铵)、氨水及H2O2用量对反应的影响.结果表明,适宜的溶剂为乙醇,最佳反应温度为80℃,助催化剂乙酸铵在溶液中的浓度不低于0.43%(ω)时能显著提高苯乙酮氨肟反应的转化率,而Al2O3的作用不明显.为了获得较高的转化率,物料中NH3/苯乙酮以及H2O2/苯乙酮的摩尔比应分别控制在2.00和1.27以上

TS-1分子筛催化苯乙酮氨肟化反应

研究了钛硅分子筛(TS-1)催化苯乙酮氨肟化反应中溶剂、反应温度、助催化剂(氧化铝和乙酸铵)、氨水及H2O2用量对反应的影响.结果表明,适宜的溶剂为乙醇,最佳反应温度为80℃,助催化剂乙酸铵在溶液中的浓度不低于0.43%(ω)时能显著提高苯乙酮氨肟反应的转化率,而Al2O3的作用不明显.为了获得较高的转化率,物料中NH3/苯乙酮以及H2O2/苯乙酮的摩尔比应分别控制在2.00和1.27以上