Kuznedelov K D, Timoshkin O A
Laboratory of Molecular Enzymology, Limnologycal Institute RAN, Irkutsk, Russia.
Mol Mar Biol Biotechnol. 1993 Oct;2(5):300-7.
The polymerase chain reaction (PCR) and direct sequencing of RNA genes were applied for phylogenetic relationship analysis among Turbellaria (flatworms). Representatives of 10 species of the genus Geocentrophora (Prorhynchidae family) were used to establish homology between nucleotides in the 5'-end portion of the 18S rRNA gene sequences. Sequence data were subdivided into 3 subsets--unpaired and basepaired (according to rRNA secondary structure) and transversion, including only transversion substitutions--that were independently analyzed to construct phylogenetic trees. Distance matrix and maximum parsimony approaches were applied to infer phylogenies. Trees were examined in terms of morphological taxonomy. The DNA sequences support the taxonomy and systematics of Baikalian flatworms. The hypothesis of Geocentrophora origin in Baikal is discussed.
聚合酶链反应（PCR）和RNA基因直接测序被应用于涡虫纲（扁形虫）的系统发育关系分析。使用了地中心涡虫属（原吻科）10个物种的代表来确定18S rRNA基因序列5'端部分核苷酸之间的同源性。序列数据被细分为3个子集——未配对和碱基配对的（根据rRNA二级结构）以及颠换，仅包括颠换替代——对这些子集进行独立分析以构建系统发育树。应用距离矩阵和最大简约法来推断系统发育。根据形态分类学对树进行了检验。DNA序列支持贝加尔湖扁形虫的分类学和系统学。讨论了地中心涡虫起源于贝加尔湖的假说。
