Mitochondrial Genomic Characteristics and Phylogenetic Analysis of 21 Species of Poaceae
The mitogenomes of different plants have their unique genomic characteristics and evolutionary patterns.Based on the NCBI-Genome database,the comparative genomics method was used to analyze the genomic characteristics and phylogenetic relation-ships of 21 Poaceae mitogenomes.The results showed that the mitogenomes of 21 Poaceae species ranged in size from 443 to 705 kb,with(A+T)content ranging from 50％to 70％,exhibiting significant base bias.The number of open reading frame(ORF),RNA edi-ting sites,coding proteins,tRNA,and repeat sequences varied in different Poaceae mitogenomes,meanwhile the copy numbers of the same type of coding protein,tRNA,and repeat sequence also vary among different mitogenomes.Among different Poaceae mitoge-nomes,the codon usage of protein-coding genes prefer using AGA(R),UCU(S),CUU(L),ACU(T),and GCU(A).Meanwhile,the protein-coding genes were also subjected to different directions and degrees of genetic selection during the mitochondrial genetic evolution in Poaceae,among which,18 protein coding genes such as mttB,ccmFn,and rpl16 were subjected to different degrees of purification(negative)selection(Ka/Ks＜1).The results of mitogenome collinearity and phylogenetic evolutionary tree constructed by neighbor joining method,which indicate that there are close phylogenetic relationships among the species from genus Oryza and Bambu-sa,the species from Aegilops,Triticum,Hordeum,and Lolium genus,as well as the species from Zea,Sorghum,Tripsacum,Chryso-pogon,Saccharum,and Eleusine genus.The results provide a reference for further revealing the structural variations and functional studies of mitogenomes during the evolutionary process of Poaceae.
NETL
NSTL
万方数据
