ABSTRACT
As abscisic acid (ABA) receptor, the pyrabactin resistance 1-like (PYR/PYL) protein (named PYL for simplicity) plays an important part to unveil the signal transduction of ABA and its regulatory mechanisms. Glycyrrhiza uralensis, a drought-tolerant medicinal plant, is a good model for the mechanism analysis of ABA response and active compound biosynthesis. However, knowledge about PYL family in G. uralensis remains largely unknown. Here, 10 PYLs were identified in G. uralensis genome. Characterization analysis indicated that PYLs in G. uralensis (GuPYLs) are relatively conserved. Phylogenetic analysis showed that GuPYL1-3 belongs to subfamily I, GuPYL4-6 and GuPYL10 belong to subfamily II and GuPYL7-9 belongs to subfamily III. In addition, transcriptome data presented various expression levels of GuPYLs under different exogenous ABA stresses. The expression pattern of GuPYLs was verified by Quantitative real-time polymerase chain reaction (qRT-PCR). The study proved that GuPYL4, GuPYL5, GuPYL8 and GuPYL9 genes are significantly up-regulated by ABA stress and the response process is dynamic. This study paves the way for elucidating the regulation mechanism of ABA signal to secondary metabolites and improving the cultivation and quality of G. uralensis using agricultural strategies.
ABSTRACT
Pyrrosia petiolosa, Pyrrosia lingua and Pyrrosia sheareri are recorded as original plants of Pyrrosiae Folium (PF) and commonly used as Chinese herbal medicines. Due to the similar morphological features of PF and its adulterants, common DNA barcodes cannot accurately distinguish PF species. Knowledge of the chloroplast (cp) genome is widely used in species identification, molecular marker and phylogenetic analyses. Herein, we determined the complete cp genomes of three original species of PF via high-throughput sequencing technologies. The three cp genomes exhibited a typical quadripartite structure with sizes ranging from 158 165 to 163 026 bp. The cp genomes of P. petiolosa and P. lingua encoded 130 genes, whilst that of P. sheareri encoded 131 genes. The complete cp genomes were compared, and five highly divergent regions of petA-psbJ, matK-rps16, ndhC-trnM, psbM-petN and psaC-ndhE were screened as potential DNA barcodes for identification of Pyrrosia genus species. The phylogenetic tree we obtained indicated that P. petiolosa and P. lingua are clustered in a single clade and, thus, share a close relationship. This study provides invaluable information for further studies on the species identification, taxonomy and phylogeny of Pyrrosia genus species.
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.