Appearance, molecule identification, and phylogenetic analysis of the three Leonurus species used for the treatment of gynecological diseases

Abstract

We analyzed and compared the three Leonurus species from appearance characteristics, intrinsic gene contents and functions, gene transcribed spacer regions (ITS2) in the nuclear genome, and the process of evolutionary development. The chloroplast genomes of them were found to be common circular structures with the four regions, the length range from 151236bp to 151689bp including the identical number of 37 tRNA and 8 rRNA. The special trans-spliced rps12 genes with two introns and three exons can be caught sight of L. sibiricus. The isoleucine (AUU) and cysteine (UGC) was the most and least abundant amino acid with the codons ending with most bases of A/U. The eleven hotspot divergent regions and four specific CDS genes were systematically counted with the highest nucleotide diversity. We cloned the DNA sequences of the two chosen IGS regions (atpH-atpI and rps15-ycf1) to develop the DNA barcodes, thus found that sixteen specific variable SNP sites and two Indel sites within the three Leonurus species. Furthermore, the ITS2 DNA sequences of 7 Leonurus species were varied after the 57th base in a total of 221 bases. In the aftermath of evolutional analysis, the three Leonurus species were significantly clustered into one great clade, while they were located at the different sub-branch with similar topology and close relationship of Phlomoides rotata based on the sequences of 64 shared nucleotide and ITS2 DNA. Thus above results can directly offer various evidence to better clarify the specific distinction among the three Leonurus species and their evolutionary history.