Chloroplast genomes of key species shed light on the evolution of the ancient genus Isoetes  

作　　者：Jovani B.S.Pereira Ana Maria Giulietti Eder S.Pires Marcele Laux Maurício T.C.Watanabe Renato R.M.Oliveira Santelmo Vasconcelos Guilherme Oliveira 

机构地区：[1]Biodiversity and Ecosystems Services Group,Instituto Tecnológico Vale,Belém,Pará,Brazil [2]Instituto de Botânica de São Paulo,São Paulo,Brazil [3]Depto.Botânica,Universidade Estadual de Feira de Santa,Feira de Santana,Bahia,Brazil [4]Environmental Genomics Group,Instituto Tecnológico Vale,Belém,Pará,Brazil

出　　处：《Journal of Systematics and Evolution》2021年第3期429-441,共13页植物分类学报（英文版）

基　　金：The authors thank the following institution for financially supporting this study:Vale(Projeto Isoetes RBRS000603.86),CAPES(88887.130628/2016-00),GCRF-RCUK(BB/P027849/1-CABANA)to GO;GO is a CNPq fellow(307479/2016-00);Additionally,this study was supported through a postdoctoral fellowship from Capes/ITV(88887.130616/2016)to JBSP.

摘　　要：Although phylogenetic studies have revealed major clades,the deepest relationships in Isoetes remain unresolved.The use of next-generation sequencing provides enormous amounts of gene sequences,which allows not only clarification of the basal relationships but also rapid radiations.Plastomes of six key Isoetes species were annotated,revealing a total of 129 or 130 genes,depending on the species.Our phylogenomic analyses comprising representatives of all major clades yielded well-supported nodes and identical topologies using maximum likelihood and Bayesian inference.The phylogenetic reconstructions detangled the deep relationships in Isoetes and illuminated the more recent radiations in the genus.A basal dichotomy was found that grouped Isoetes spp.from Brazil and South Africa into a clade sister to the remaining Isoetes groups.Interestingly,I.andicola was found to be sister to the North American species complex.Genomic trait mapping analysis showed that the missing introns in the atpF and clpP genes were well conserved in two major clades.The absence of trnK-UUU was observed in the Brazilian tropical species and in I.velata.Among lycophytes,the gene trnR-CCG was missing only in I.eludens.In general,genomic traits such as the presence or absence of internal stop codons,a tRNA,and an intron were revealed to be conserved within groups,suggesting that these genomic traits might reveal vital information about the evolution of the genus.This study will contribute to understanding the diversification of Isoetes and the establishment of a better framework to address the evolutionary history of the genus.

关 键 词：internal stop codons ISOETES LYCOPHYTES next-generation sequencing phylogenomic RNA editing TRNA 

分 类 号：Q94[生物学—植物学]