Chloroplast Genomic Analysis of Pyrrosia assimilis / 中国实验方剂学杂志

ABSTRACT

Objective:The complete chloroplast genome of Pyrrosia assimilis was sequenced, its sequence characteristics was analyzed and herbgenomics of P. assimilis was discussed. Method:Its complete chloroplast genome sequence was determined through high-throughput sequencing technology, and its structural characteristics and phylogenetic relationships were analyzed by bioinformatics. Result:The chloroplast genome of P. assimilis was a circular double-chain structure with a total length of 154 964 bp, and the total content of guanine and cytosine (GC) was 41.2%. A total of 131 genes were annotated, including 88 protein-coding genes, 35 transfer RNA (tRNA) genes and 8 ribosomal RNA (rRNA) genes. A total of 43 dispersed repetitive sequences and 56 simple sequence repeats (SSRs) were detected. The frequency of codon encoding leucine was the highest, while the number of codon encoding tryptophan was the lowest. Five highly divergent regions (psbA, rrn16, petA-psbJ, ndhC-trnM, and psbM-petN) were screened, phylogenetic analysis showed that P. assimilis was closely related to P. bonii. Conclusion:Comparative analysis of the complete chloroplast genome of P. assimilis reveals that non-coding regions exhibited a higher divergence than the coding regions, the large single copy region (LSC) and small single copy region (SSC) are more divergent than the reverse repeat region (IR), the selected five highly variable regions can be used as specific DNA barcodes for identification of Pyrrosia species. Study on the chloroplast genome of P. assimilis can provide a reference for the molecular identification, genetic transformation, expression of resistance protein and secondary metabolism pathway analysis of other Pyrrosia medicinal plants.