Plant Diversity ›› 2018, Vol. 40 ›› Issue (03): 127-137.DOI: 10.1016/j.pld.2018.04.003

• Articles • Previous Articles    

Plastome characteristics of Cannabaceae

Huan-Lei Zhanga,b, Jian-Jun Jina,b, Michael J. Moorec, Ting-Shuang Yia, De-Zhu Lia   

  1. a Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China;
    b Kunming College of Life Sciences, University of Chinese Academy of Sciences, Kunming 650201, China;
    c Department of Biology, Oberlin College, Oberlin, OH 44074, USA
  • Received:2018-03-17 Revised:2018-04-18 Online:2018-06-25 Published:2018-07-13
  • Contact: Ting-Shuang Yi, De-Zhu Li
  • Supported by:

    This study was supported by grants from the National Natural Science Foundation of China,key international (regional) cooperative research project (31720103903),The Strategic Priority Research Program of the Chinese Academy of Sciences (XDPB0201).

Abstract:

Cannabaceae is an economically important family that includes ten genera and ca.117 accepted species. To explore the structure and size variation of their plastomes,we sequenced ten plastomes representing all ten genera of Cannabaceae.Each plastome possessed the typical angiosperm quadripartite structure and contained a total of 128 genes.The Inverted Repeat (IR) regions in five plastomes had experienced small expansions (330-983 bp) into the Large Single-Copy (LSC) region.The plastome of Chaetachme aristata has experienced a 942-bp IR contraction and lost rpl22 and rps19 in its IRs.The substitution rates of rps19 and rpl22 decreased after they shifted from the LSC to IR.A 270-bp inversion was detected in the Parasponia rugosa plastome,which might have been mediated by 18-bp inverted repeats.Repeat sequences,simple sequence repeats,and nucleotide substitution rates varied among these plastomes. Molecular markers with more than 13% variable sites and 5% parsimony-informative sites were identified,which may be useful for further phylogenetic analysis and species identification.Our results show strong support for a sister relationship between Gironniera and Lozanell (BS=100).Celtis,Cannabis-Humulus,Chaetachme-Pteroceltis,and Trema-Parasponia formed a strongly supported clade,and their relationships were well resolved with strong support (BS=100).The availability of these ten plastomes provides valuable genetic information for accurately identifying species,clarifying taxonomy and reconstructing the intergeneric phylogeny of Cannabaceae.

Key words: Plastome, IR expansion/contraction, Repeats, SSR, Sequence divergence, Phylogenomics