Phylogeny and biogeography of the genus Ainsliaea (Asteraceae) in the Sino-Japanese region based on nuclear rDNA and plastid DNA sequence data.
OBJECTIVE
The flora of the Sino-Japanese plant region of eastern Asia is distinctively rich compared with other floristic regions in the world. However, knowledge of its floristic evolution is fairly limited. The genus Ainsliaea is endemic to and distributed throughout the Sino-Japanese region. Its interspecific phylogenetic relationships have not been resolved. The aim is to provide insight into floristic evolution in eastern Asia on the basis of a molecular phylogenetic analysis of Ainsliaea species.


METHODS
Cladistic analyses of the sequences of two nuclear (ITS, ETS) and one plastid (ndhF) regions were carried out individually and using the combined data from the three markers.


RESULTS
Phylogenetic analyses of three DNA regions confirmed that Ainsliaea is composed of three major clades that correspond to species distributions. Evolution of the three lineages was estimated to have occurred around 1.1 MYA during the early Pleistocene.


CONCLUSIONS
The results suggest that Ainsliaea species evolved allopatrically and that the descendants were isolated in the eastern (between SE China and Japan, through Taiwan and the Ryukyu Islands) and western (Yunnan Province and its surrounding areas, including the Himalayas, the temperate region of Southeast Asia, and Sichuan Province) sides of the Sino-Japanese region. The results suggest that two distinct lineages of Ainsliaea have independently evolved in environmentally heterogeneous regions within the Sino-Japanese region. These regions have maintained rich and original floras due to their diverse climates and topographies.
Mitsui
Yuki
Y
Graduate School of Human and Environmental Studies, Kyoto University, Yoshida Nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan. yuuki1009@lagoon.ocn.ne.jp
Chen
Shao-Tien
ST
Zhou
Zhe-Kun
ZK
Peng
Ching-I
CI
Deng
Yun-Fei
YF
Setoguchi
Hiroaki
H
D019659:Asteraceae / Q000145:classification* / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry*; D005202:Asia, Eastern; D049810:Genetic Speciation; D005843:Geography; D010802:Phylogeny; D018087:Plastids / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D021903:DNA, Ribosomal Spacer