DNA序列在蕨类分子系统学研究中的应用

Application of DNA Sequences in Pteridophyte Phylogenetic Study

在分子系统学研究中,目的基因或者基因片段的选择是最关键的一步,由于进化速率的差异,不同的DNA序列适用于不同分类阶元的系统发育研究。本文综述了目前蕨类分子系统发育研究中常用的DNA序列分析,它们分别来自叶绿体基因组、核基因组和线粒体基因组,着重阐明叶绿体基因在蕨类分子系统学研究中的应用。本文还简要介绍了分子系统学研究中常见的问题及解决方法(如内类群和外类群的选择,适宜DNA片段的选择策略),总结了目前蕨类植物分子系统学研究所取得的进展和研究现状,展望了当今国际蕨类分子系统学的研究趋势。

DNA sequences,because of their disparity in rate of evolution,are suitable for phylogenetic study at different taxonomic levels.Therefore,selecting the most appropriate DNA sequence to address a certain phylogenetic issue is important.This paper summarizes the appropriate range of some DNA sequences that are commonly used in current pteridophyte molecular phylogenetics,which comprises sequences from three plant genomes(chloroplast,nucleotide,and mitochondria),especially focuses on the usage of chloroplast DNA regions.Problems in reconstructing the fern phylogeny and strategies to overcome these problems(including ingroup and outgroup selection,and the choice of the appropriate DNA region) are briefly discussed.This paper represents recent progress in molecular phylogenetics and points out the status of and prospects for pteridological research in China.