Based on whole-genome identification of the TPS gene family in Perilla frutescens and screening, cloning, bioinformatics, and expression analysis of the synthetic enzyme for the insect-resistant component germacrene D, this study lays the foundation for understanding the biological function of the TPS gene family and the insect resistance mechanism in P. frutescens. This study used bioinformatics tools to identify the TPS gene family of P. frutescens based on its whole genome and predicted the physicochemical properties, systematic classification, and promoter cis-elements of the proteins. The relative content of germacrene D was detected in both normal and insect-infested leaves of P. frutescens, and the germacrene D synthase was screened and isolated. Gene cloning, bioinformatics analysis, and expression profiling were then performed. The results showed that a total of 99 TPS genes were identified in the genome, which were classified into the TPS-a, TPS-b, TPS-c, TPS-e/f, and TPS-g subfamilies. Conserved motif analysis showed that the TPS in P. frutescens has conserved structural characteristics within the same subfamily. Promoter cis-element analysis predicted the presence of light-responsive elements, multiple hormone-responsive elements, and stress-responsive elements in the TPS family of P. frutescens. Transcriptome data revealed that most of the TPS genes in P. frutescens were highly expressed in the leaves. GC-MS analysis showed that the relative content of germacrene D significantly increased in insect-damaged leaves, suggesting that it may act as an insect-resistant component. The germacrene D synthase gene was screened through homologous protein binding gene expression and was found to belong to the TPS-a subfamily, encoding a 64.89 kDa protein. This protein was hydrophilic, lacked a transmembrane structure and signal peptide, and was predominantly expressed in leaves, with significantly higher expression in insect-damaged leaves compared to normal leaves. In vitro expression results showed that germacrene D synthase tended to form inclusion bodies. Molecular docking showed that farnesyl pyrophosphate(FPP) fell into the active pocket of the protein and interacted strongly with six active sites. This study provides a foundation for further research on the biological functions of the TPS gene family in P. frutescens and the molecular mechanisms underlying its insect resistance.
Perilla frutescens/chemistry* ; Plant Proteins/chemistry* ; Multigene Family ; Sesquiterpenes, Germacrane/metabolism* ; Alkyl and Aryl Transferases/chemistry* ; Phylogeny ; Gene Expression Regulation, Plant

Previous studies have shown that STAT3 plays a vital role in the genesis and progression of cancer. In this study, we investigated the relationship between the JAK2/STAT3 signalling pathway and germacrone-induced apoptosis in HepG2 cells. HepG2 cells were incubated with germacrone for 24 h, the protein expression of p-STAT3, STAT3, p-JAK2 and JAK2 was detected by Western Blotting, and RT-PCR was used to determine the expression of STAT3, p53, Bcl-2 and Bax at transcriptional levels. Besides that, HepG2 cells were pre-treated with AG490 or IL-6 for 2 h, and then incubated with germacrone for 24 h. The expression of p-JAK2, JAK2, p-STAT3, STAT3, p53, Bax and Bcl-2 was detected by Western blotting. The activity of HepG2 cells was tested by MTT assay. The apoptosis of HepG2 cells and levels of reactive oxygen species (ROS) were flow cytometrically measured. The results showed that germacrone exposure decreased p-STAT3 and p-JAK2 and regulated expression of p53 and Bcl-2 family members at the same time. Moreover, IL-6 enhanced the activation of the JAK2/STAT3 signalling pathway and therefore attenuated the germacrone-induced apoptosis. Suppression of JAK2/STAT3 signalling pathway by AG490, an inhibitor of JAK2, resulted in apoptosis and an increase in ROS in response to germacrone exposure. We therefore conclude that germacrone induces apoptosis through the JAK2/STAT3 signalling pathway.
Apoptosis ; drug effects ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; administration & dosage ; Hep G2 Cells ; Humans ; Janus Kinase 2 ; metabolism ; STAT3 Transcription Factor ; metabolism ; Sesquiterpenes, Germacrane ; administration & dosage ; Signal Transduction ; drug effects

AIMTo study the absorption of zedoary oil in intestine of rat.

METHODSIn situ single pass perfusion model was used and the concentrations of three components in perfusate were determined by HPLC in combination with diode array detection.

RESULTSThe P(app) s of curcumol, curdione and germacrone were all low and had no significant difference (P > 0.05) at zedoary oil concentration of 0.4, 0.8 and 1.2 mg x mL(-1) in transmucosal fluid or in four different regions of intestine of rat [duodenum, jejunum, ileum, colon]. The absorption rates of germacrone and curdione were faster than curcumol's in this study.

CONCLUSIONThe zedoary oil concentration in transmucosal fluid had no significant effect on the P(app) s within the scope of 0.4-1.2 mg x mL(-1). The absorption of curcumol, curdione and germacrone showed the passive diffusion process, and didn't contain a special absorption window.

Animals ; Biological Transport ; Colon ; metabolism ; Curcuma ; chemistry ; Duodenum ; metabolism ; Ileum ; metabolism ; In Vitro Techniques ; Intestinal Absorption ; Jejunum ; metabolism ; Male ; Perfusion ; Plant Oils ; chemistry ; isolation & purification ; pharmacokinetics ; Plants, Medicinal ; chemistry ; Rats ; Rats, Wistar ; Sesquiterpenes ; isolation & purification ; pharmacokinetics ; Sesquiterpenes, Germacrane ; isolation & purification ; pharmacokinetics