rbcL sequence divergence and phylogenetic relationships in Saxifragaceae sensu lato.
rbcL sequence divergence and phylogenetic relationships in Saxifragaceae sensu lato.
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虎耳草科 rbcL 序列分歧和系统发育关系。
DOI：
10.1073/pnas.87.12.4640
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发表时间：
1990
影响因子：
11.1
通讯作者：
M. Durbin
中科院分区：
文献类型：
--
作者：
D. Soltis;P. Soltis;M. Clegg;M. Durbin
尽管进行了深入的形态学分析，但在更高的分类学水平（科及以上）上，系统发育关系往往知之甚少。广义虎耳草科就是一个很好的例子，它代表了被子植物在更高分类水平上的主要系统发育问题之一。根据最初的定义，该科是由15个亚科组成的草本和木本分类群的异质组合。虽然最近的分类从根本上修改了这一方案，关于这些亚科的界限，分类等级或关系存在很少的协议。虎耳草科的分类处理中经常出现的差异，促使叶绿体基因序列的权力，以解决这个家庭和虎耳草科和其他主要植物谱系之间的系统发育关系的调查。基因rbcL（核酮糖-1，5-二磷酸羧化酶，大亚基）的序列数据显示：（i）广义虎耳草科至少是并系的，可能是多系的，（ii）梅花草属和Brexia属只是与虎耳草科的其他成员远亲，和（iii）茄科（Asteridae亚类）的代表似乎比传统上保持更密切相关的虎耳草科（糖苷酶亚类）。这些数据说明了价值的叶绿体基因序列数据在解决遗传，因此系统发育，最复杂的分类群体的成员之间的关系。
Phylogenetic relationships are often poorly understood at higher taxonomic levels (family and above) despite intensive morphological analysis. An excellent example is Saxifragaceae sensu lato, which represents one of the major phylogenetic problems in angiosperms at higher taxonomic levels. As originally defined, the family is a heterogeneous assemblage of herbaceous and woody taxa comprising 15 subfamilies. Although more recent classifications fundamentally modified this scheme, little agreement exists regarding the circumscription, taxonomic rank, or relationships of these subfamilies. The recurrent discrepancies in taxonomic treatments of the Saxifragaceae prompted an investigation of the power of chloroplast gene sequences to resolve phylogenetic relationships within this family and between the Saxifragaceae and other major plant lineages. Sequence data from the gene rbcL (ribulose-1,5-bisphosphate carboxylase, large subunit) reveal that (i) Saxifragaceae sensu lato is at least paraphyletic, and probably polyphyletic, (ii) the genera Parnassia and Brexia are only distantly related to other members of Saxifragaceae, and (iii) representatives of the Solanaceae (subclass Asteridae) appear more closely related to Saxifragaceae (subclass Rosidase) than traditionally maintained. These data illustrate the value of chloroplast gene sequence data in resolving genetic, and hence phylogenetic, relationships among members of the most taxonomically complex groups.