The Chloranthus sessilifolius genome provides insight into early diversification of angiosperms

Jianxiang Ma,Dandan Wang,Congcong Dong,Ying Wu,Ying Li,Jiao Yang,Wenjie Mu,Renping Xu,Zhenyue Wang,Yongzhi Yang,Nawal Shrestha,Pengchuan Sun,Jianquan Liu

doi:10.1038/s41467-021-26931-3

Jianxiang Ma, Dandan Wang + Show 11 more

Open Access

https://doi.org/10.1038/s41467-021-26931-3

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Journal: Nature Communications	Publication Date: Nov 26, 2021
Citations: 32	License type: open-access

Affiliation: Lanzhou University, Sichuan University

Abstract

Most extant angiosperms belong to Mesangiospermae, which comprises eudicots, monocots, magnoliids, Chloranthales and Ceratophyllales. However, phylogenetic relationships between these five lineages remain unclear. Here, we report the high-quality genome of a member of the Chloranthales lineage (Chloranthus sessilifolius). We detect only one whole genome duplication within this species and find that polyploidization events in different Mesangiospermae lineage are mutually independent. We also find that the members of all floral development-related gene lineages are present in C. sessilifolius despite its extremely simplified flower. The AP1 and PI genes, however, show a weak floral tissue-specialized expression. Our phylogenomic analyses suggest that Chloranthales and magnoliids are sister groups, and both are together sister to the clade comprising Ceratophyllales and eudicots, while the monocot lineage is sister to all other Mesangiospermae. Our findings suggest that in addition to hybridization, incomplete lineage sorting may largely account for phylogenetic inconsistencies between the observed gene trees.

Highlights

Most extant angiosperms belong to Mesangiospermae, which comprises eudicots, monocots, magnoliids, Chloranthales and Ceratophyllales
We further assessed the quality of the C. sessilifolius genome and we found that more than 99.93% of Illumina short reads could be mapped to the assembly (Supplementary Table 2)
We conclude that our C. sessilifolius genome has high degrees of both accuracy and completeness (Fig. 1b)

Summary

Introduction

Most extant angiosperms belong to Mesangiospermae, which comprises eudicots, monocots, magnoliids, Chloranthales and Ceratophyllales. A set of 1689 single-copy orthologous genes were identified with SonicParanoid[42] using genomes of 14 plants, which included one gymnosperm (Ginkgo biloba) as the outgroup, three species from the ANA-grade (A. trichopoda, Euryale ferox, and N. colorata), two magnoliids (L. chinense and Cinnamomum kanehirae), three monocots (Oryza sativa, El. guineensis, and Apostasia shenzhenica), three eudicots (Aquilegia coerulea, Prunus persica, and V. vinifera), C.

Results

Conclusion