Folding and post-translational modification of proteins are vital for their proper functionality, with various functional regulatory systems playing significant roles, including molecular chaperone systems, ubiquitination systems, phosphorylation systems, acetylation systems, etc. Precise regulations of these systems have emerged as an important trend in drug development. This review systematically summarizes the molecular control strategies related to protein folding and post-translational modification, with a specific focus on the molecular chaperone system and the strategy of heterobifunctional molecules. On one hand, based on the similarities and differences in molecular mechanisms and design strategies, we summarize the drug development process targeting the molecular chaperone system. On the other hand, we discuss the design principles and characteristics of dual-functional molecules, and summarize their applications and developments in the precise control of post-translational modifications, aiming to provide new insights for future design.

Protein phosphorylation modification is an important mechanism of physiological regulation that is closely related to protein biological functions. In particular, protein kinases are responsible for catalyzing the phosphorylation process of proteins, and phosphatases are responsible for catalyzing the dephosphorylation process of phosphorylation-modified proteins, which together mediate the achievement of dynamic and reversible phosphorylation modifications of proteins. Abnormal phosphorylation levels of proteins contribute to the development of many diseases, such as cancer, neurodegenerative diseases, and chronic diseases. Therefore, rational design of small molecules to regulate protein phosphorylation is an important approach for disease treatment. Based on the mechanism of protein phosphorylation regulation, small molecule drug design strategies can be classified into three types, protein kinase modulators, phosphatase modulators, and bifunctional molecules with proximity-mediated mechanism. This review emphasizes the above three small molecule design strategies for targeting protein phosphorylation regulation, including molecular design ideas, research progress and current challenges, and provides an outlook on small molecule modulators targeting protein phosphorylation modification.

The ubiquitin-proteasome system (UPS) is responsible for protein degradation in both normal and pathological states. E3 ligases selectively attach ubiquitin to specific substrates, which is essential for regulating cellular homeostasis. The function of E3 ligases has been associated with a variety of diseases, such as cancer and cardiovascular disease. The discovery of E3 ligands can help regulate E3 ligases, thus expanding new ideas for disease treatment. Targeted protein degradation (TPD) drugs, including proteolysis targeting chimera (PROTAC), have become increasingly popular in recent years due to their dependence on E3 ligands. In this paper, we review the discovery techniques of E3 ligands, including activity-based protein mapping, fragment-based drug discovery, and library-based methods, and briefly introduce the protein interaction detection techniques involved in the ligand discovery techniques, in the hope of providing certain ideas for the future discovery of E3 ligands as well as the treatment of diseases.

The deubiquitinases (DUBs), as the crucial peptidohydrolases in the ubiquitin system, can reverse and strictly regulate ubiquitination and play key roles in various biological processes, including the regulation of protein stability, cell signal transduction. Ubiquitin-specific protease 28 (USP28) involves multiple cancer-related signaling pathways by enhancing the stability of various cancer-related proteins, and is closely associated with the progression of colorectal, breast cancer, lung carcinomas, and pancreatic cancer. USP28 has been considered as a promising drug target in anticancer therapy, and the development of USP28 inhibitors has made some progress. In this article, we review the structure of USP28 and its interaction with substrates, discuss the research progress of USP28 in cancers and summarize the development of USP28 inhibitors.

Protein-protein interactions (PPIs) are not only crucial for the assembly of protein complexes but also fundamental for maintaining normal biological functions. These interactions are vital for protein structure and biological functionality and play a central role in cellular signaling, metabolic pathways, and regulatory networks. The 14-3-3 protein, highly conserved and widely expressed in eukaryotes, primarily recognizes and binds to its partner proteins to participate in essential life processes such as cell cycle control, signal transduction, and energy metabolism. This review discusses the role of dysregulated PPIs between 14-3-3 proteins and their partner proteins such as estrogen receptor α (estrogen receptor α, ERα), RAF proto-oncogene serine/threonine-protein kinase (C-RAF/RAF-1), and p53 in the onset and progression of tumors, focusing on the research progress of 14-3-3/ERα, 14-3-3/C-RAF, and 14-3-3/p53 molecular glues. These molecular glues, by mimicking or enhancing the phosphorylation sites of serine on partner proteins, form covalent bonds, salt bridges, and hydrogen bonds with 14-3-3 proteins, thereby enhancing the stability of PPIs and effectively intervening in protein activity and signaling under pathological conditions. Additionally, this article explores the potential of this chemical intervention strategy in clinically suppressing tumor progression, providing a theoretical foundation and practical guidance for future research directions.

Heat shock protein 70 (Hsp70) is a class of molecular chaperones essential for maintaining protein homeostasis in cells. Hsp70s also play important roles in the pathogenesis of a variety of diseases, including cancer, neurodegenerative diseases and infectious diseases, which makes them potential targets for the treatment of these diseases. It is necessary to develop small molecule inhibitors to validate this class of important therapeutic targets. In recent years, the discovery of small molecule inhibitors for Hsp70s has made remarkable progress, and Hsp70 inhibitors with different modalities have been reported. In this paper, Hsp70 and relevant diseases are briefly introduced, and the discovery of Hsp70 small molecule inhibitors with distinct modalities are summarized, providing reference for the further discovery and development of Hsp70 small molecule inhibitors.

Heat shock protein 90 (HSP90) is a crucial molecular chaperone responsible for the activation and maturation of client proteins. Targeting HSP90 can effectively inhibit cancer cell proliferation by either competitively occupying the ATP-binding site or disrupting the protein-protein interaction sites between HSP90 and its co-chaperones. Therefore, studying the recognition and function of HSP90 binding sites is essential for molecular discovery. This study focuses on peptide P1, revealing its dual binding mechanism with HSP90. P1 is capable of simultaneously interacting with both the ATP-binding site of HSP90 and the binding interface with the co-chaperone CDC37 (cell division cycle 37). Through ATPase and Co-IP assays, we found that P1 effectively inhibits both ATP activity and the protein interaction between HSP90 and CDC37, providing a novel approach for developing new inhibitors targeting the HSP90 chaperone system.

The phenomenon of bacterial drug resistance is becoming more and more serious. Natural products, as an important resource for drug discovery, can play a role by regulating protein post-translational modifications related to bacterial infection and inflammatory responses. This provides a valuable compound library for the research and development of new antibacterial drugs. In this present research, dioscin and diosgenin were isolated and identified from Dioscorea nipponica Rhizoma, which both exhibited antibacterial activities, with stronger inhibitory on Gram-positive bacteria (G⁺) than Gram-negative bacteria (G^-). Compared these two compounds, diosgenin showed stronger antibacterial activity than dioscin. In vivo experiments confirmed that diosgenin provided better protection against MRSA-induced sepsis in mice compared to dioscin, which could significantly improve survival rates, reduce bacterial colony counts in infected organs, alleviate pathological damage, and decrease inflammatory cytokine levels in mice. The in vivo study was approved by the Animal Ethics Committee of the PLA Air Force Military Medical University (Grant No. 20230188). Network pharmacology results also revealed that diosgenin could target inflammatory pathways, exerting dual antibacterial and anti-inflammatory activities during bacterial infection therapy.

The anti-apoptotic members of Bcl-2 family proteins, Bcl-2 and Mcl-1, are considered therapeutic targets of various cancers. In this article, we developed four hydrophobic tag (HyT)-based protein degraders of Bcl-2/Mcl-1, based on a Bcl-2/Mcl-1 dual inhibitor S1-6, and tested their capability in Bcl-2/Mcl-1 degradation and apoptotic induction in MCF-7 cells. Interestingly, different linkers in the HyT degraders led to selective Bcl-2/Mcl-1 degradation, though the degraders S1-D1-S1-D4 maintained the pan-Bcl-2 family binding capacity. Among them, S1-D2 and S1-D4, two compounds bearing a hydrophobic linker or a PEG linker, were observed to potently and selectively induce the ubiquitination and proteasomal degradation of Bcl-2 and Mcl-1 in living cells, with a degradation rate of more than 80% or 60%, respectively. Moreover, the HyT-based degraders showed increased lethality of cancer cells compared to the parent inhibitor S1-6, demonstrating that the advantage of degraders to the occupancy-based inhibitors.

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates gene expression in a range of cells, including immune and epithelial cells. AhR signaling plays important roles in the immune system in both health and disease states. Tapinarof is a first-in-class small-molecule topical therapeutic AhR modulating agent launched for the treatment of psoriasis. To improve the activity and chemical stability of Tapinarof, a series of 2-phenylchromen-4-one derivatives were designed, synthesized and evaluated as novel AhR agonists. Compounds 5a, 5c, 5e and 5f potently activated AhR with an EC₅₀ value of 7, 9, 6 and 6 nmol·L^-1, respectively, which are 10-14 fold more potent than Tapinarof. Compounds 5a and 5e exhibit comparable inhibitory effects on IFN-γ production as Tapinarof. Furthermore, compounds 5a-5f exhibited favorable photochemical stability compared to Tapinarof. The compounds may eventually serve as lead compounds for the development of new AhR agonists.

Insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) is a recognition protein for N⁶-methyladenosine (m⁶A), mediating the stability of downstream mRNA, and is a promising anti-tumor target. Based on the lead compound 1g from previous screening, this study designed and synthesized 52 IGF2BP2 small molecule inhibitors using thiazole hydrazone as the parent nucleus. Among them, 9g, 10g, 37g, 47g and 52g showed good inhibitory activities. This work represents an initial exploration in the development of small molecule inhibitors targeting IGF2BP2, using thiazolehydrazone as the core structure. It lays a foundation for subsequent related research.

As a key epigenetic regulator, histone deacetylases (HDACs) play a crucial role in cancer development. Small molecule HDAC inhibitors have been shown to inhibit tumor proliferation and induce apoptosis, attracting significant research attention. In this study, we designed and synthesized a series of novel saccharin derivatives as HDAC inhibitors. Biological experiments demonstrated that the target compound 9a exhibited superior HDACs inhibition activity to vorinostat and demonstrating promising in vitro and in vivo anti-tumor activity against triple-negative breast cancer (TNBC). All animal experiments in this study were performed in strict accordance with the protocols approved by the Ethical Committee of School of Pharmaceutical Sciences in Shandong University (Approval No. 230094). This work represents an initial exploration of developing saccharin-based HDAC inhibitors, and the active compound 9a could serve as a lead compound for further study.

The gut microbiota plays a crucial role in the development of colorectal cancer (CRC). The imbalanced gut microbiota causes damage to the body and disrupts bile acids metabolism, increases susceptibility to CRC, and affects the signaling of farnesol X receptor (FXR), thereby promoting CRC progression. Traditional Chinese medicine has unique advantages in the treatment of CRC due to its synergistic regulatory effects of multiple components, targets, and pathways. It can regulate gut microbiota, intervene in bile acids metabolism, and activate its receptor FXR to inhibit the occurrence and development of CRC. Based on this, this article discusses the main role of the gut microbiota-bile acids-FXR axis in the development of CRC, and reviews the anti CRC effects and mechanisms of traditional Chinese medicine intervention on gut microbiota-bile acids-FXR axis, in order to provide new ideas and methods for the prevention and treatment of CRC.

Gut microbiome and their metabolites are closely related to human diseases, which influence the development of diseases by interacting with receptors. G protein-coupled receptor (GPCR) is a receptor superfamily that exists on the surface of cell membrane, which is involved in a wide range of human physiological activities. GPCR is currently considered as important drug targets. Traditional Chinese medicines (TCM) are characterized by multi-components, multi-targets, and multi-pathways. More and more studies have demonstrated that TCM can ultimately intervene in diseases by modulating gut microbiome and their metabolites, affecting their interactions with GPCR. This review discusses the status of gut microbiome and human diseases, the interactions of gut microbiome and their metabolites with GPCR, and the status of GPCR drug development. Based on the above contents, a new model of "TCM-gut microbiome panel-GPCR-disease" is proposed. The interactions between active ingredients of TCM, gut microbiome panel, and GPCR and their effects on disease are elucidated through multi-omics techniques. This review will provide new ideas for analyzing the pharmacological mechanism of TCM efficacy and searching for new targets of TCM.

Janus kinase (JAK) and histone deacetylase (HDAC) referred to as crucial targets in autoimmune diseases and cancers have achieved quite success in the treatment of these diseases. Until now, several JAK and HDAC inhibitors have been approved. Recently, developing single multi-targeting inhibitors including JAK/HDAC dual inhibitors based on network pharmacology has made significant progress in improving therapeutic efficacy, reducing toxic and side effects, and overcoming drug resistance. In this review, we summarize novel JAK/HDAC dual inhibitors as well as JAK/HDAC-based triple-targeting inhibitors, in order to provide reference for the discovery of novel JAK/HDAC dual inhibitor.

As a major global public health problem, pulmonary diseases threaten human life and health while causing a huge economic burden. The messenger RNA (mRNA)-based inhalation preparation, which effectively targets pulmonary cells can overcome the problems of traditional therapy, such as high side effects, low pulmonary bioavailability, and difficulty in synthesizing target proteins in vitro, thus providing new ideas for the treatment of pulmonary diseases. However, as the lung structure is complex and mRNA has trouble entering cells, researchers have been attempting to develop a suitable nano delivery system for higher delivery efficiency. This review introduces the barriers to pulmonary delivery, discusses the recent research development of the mRNA pulmonary delivery systems, including lipid nanoparticles, polymeric nanoparticles, polypeptides and exosomes, summarizes their limitations and looks forward to the application of mRNA inhalation preparations.

This study aimed to investigate the therapeutic effect and possible mechanism of carboxyamidotriazole (CAI) on imiquimod (IMQ)-induced psoriasis-like mice model and M5 (IL-1α, IL-17A, IL-22, TNF-α and oncostatin M)-induced keratinocytes model of psoriasis. The severity of psoriasis-like skin lesion in mice was evaluated by psoriasis area and severity index (PASI) score. The histopathological changes of skin were examined by hematoxylin-eosin staining and Baker score was calculated. The levels of pro-inflammatory cytokines in skin were measured by enzyme-linked immunosorbent assay. Transcriptome sequencing technique was used to analyze differentially expressed genes (DEGs) and real-time quantitative PCR (qPCR) was used to detect mRNA expressions. The animal experiments conducted in this study were approved by the Institutional Animal Care Use & Welfare Committee of Institute of Basic Medical Sciences, Chinese Academy of Medical Science (grant No. ACUC-A02-2022-115). The results showed that CAI significantly improved the severity of psoriasis-like lesion, reduced PASI score, attenuated pathological changes, decreased Baker score and inhibited the levels of IL-1β, IL-6, IL-17A, IL-23 and TNF-α in skin of IMQ-induced mice. Transcriptome sequencing analysis revealed that regulating keratinocytes and their mediated keratinization might be involved in the mechanism of CAI. Further qPCR study validated that CAI down-regulated the mRNA expression of DEG S100a7. Moreover, the keratinocyte model of psoriasis was established by stimulating HaCaT cells by M5. It was shown that CAI decreased the mRNA expression levels of S100a7, Il1β, Il6, Il17, Il23 and Ccl20, which were up-regulated by M5 stimulation. In conclusion, CAI might have a good therapeutic efficacy on psoriasis, and its mechanism was related to regulate the function of keratinocytes and downregulate cytokines and S100a7.

Heart failure with preserved ejection fraction (HFpEF) accounts for about half of the number of patients with heart failure. In addition to the typical features of heart failure such as myocardial stiffness and diastolic function impairment, the key characteristic of HFpEF is the normal left ventricular ejection fraction, which increases the difficulty of clinical diagnosis. QiShenYiQi Dripping Pills (QSYQ) is a standardized traditional Chinese medicine approved by the China Food and Drug Administration (CFDA), and many clinical studies have demonstrated the efficacy and safety of QSYQ in the treatment of heart failure with reduced ejection fraction, but the role of QSYQ in HFpEF has not been clarified. In this paper, high fat diet (HFD) and drinking water containing N-nitro-L-arginine methyl ester (L-NAME, 0.5 g·L^-1, pH=7.4) were used in C57BL/6N male mice to construct the classical HFpEF model (the experiment was approved by the Animal Ethics Committee of Hefei University of Technology, the approval number is HFUT20220921002), and at the 8^th week, the mice were dosed with ① empagliflozin, ② low-dose QSYQ (LQ), ③ high-dose QSYQ (HQ), ④ empagliflozin plus low-dose QSYQ (ELQ) for 4 weeks, the body weight of the mice was recorded during the experiment, echocardiography, blood pressure and glucose tolerance were detected and the exercise capacity of mice was evaluated, and pathological and biochemical experiments were used to detect cardiac fibrosis, liver fibrosis and serum biochemical indexes in mice, RNAseq assay was performed with mice heart tissues. The results showed that QSYQ as well as QSYQ+empagliflozin could significantly reduce the body weight, improve diastolic function and hypertension, improve glucose tolerance and enhance exercise ability of HFpEF mice. At the biochemical and molecular levels, QSYQ and QSYQ+empagliflozin can reduce the cross-sectional area of cardiomyocytes and reduce cardiac collagen contents, thereby alleviating myocardial hypertrophy and fibrotic phenotypes, and improve metabolic disorders. The RNAseq results suggest that the function of QSYQ in improving HFpEF may be related to calsequestrin 1. In conclusion, this study shows that QSYQ and QSYQ+empagliflozin can significantly improve HFpEF-related cardiac dysfunction and metabolic disorders, which provides a theoretical basis for the clinical treatment of HFpEF.

The study aims to investigate and compare the effects of probiotics and docosahexaenoic acid (DHA) with the Alzheimer's disease (AD) therapeutic drug donepezil on the learning cognition and brain damage related indexes in AD mice, and to provide experimental basis for its treatment of AD. All animal experiments were approved by the Ethics Committee of the Henan University of Chinese Medicine (ethics number DWLL2018080003). Fifty male C57BL/6J mice were randomly assigned to one of five groups: sham-operated, model, donepezil (10 mg·kg^-1), probiotic (2.7×10⁹ CFU·d^-1), and DHA (0.104 g·kg^-1). Except for the sham-operated group, the AD animal model was established by injecting Aβ_25-35 (200 μmol·L^-1) in the lateral ventricle, followed by gavage administration for 4 weeks. In all mouse groups, learning memory ability, neuronal morphology in the hippocampus, apoptosis of primary hippocampal cells, and immune cell levels were detected. The levels of Aβ_1-42, Aβ_1-40, p-Tau, AchE, Ach, oxidative stress, glial cell activation, and the inflammatory factors IL-1β, IL-10, and TNF-α in the brain tissue of mice were also detected. 16S rDNA sequencing was used to further investigate the effects of donepezil and probiotics on AD. Donepezil, probiotics and DHA improved cognitive deficits and enhanced learning memory in Aβ_25-35-induced mice by increasing locomotion time, locomotion distance, autonomic alternation rate, and shortening the time to reach the plateau; it significantly attenuated Aβ_25-35-induced brain injury and neuroinflammation in mice by decreasing Aβ_1-42, Aβ_1-40, p-Tau, AchE, IL-1β, TNF-α, and MDA and increasing the levels of Ach, IL-10, GSH-Px, and T-SOD in brain tissues, as well as decreasing the activation of glial cells, and had a modulatory effect on immune cells. 16S rDNA sequencing shows that both donepezil and probiotics restore flora homeostasis and that differential bacteria are strongly associated with cognition, AD pathology, and neuroinflammation. Combining all indicators, donepezil and probiotics were more effective than DHA. All in all, donepezil, probiotics and DHA ameliorate Aβ_25-35-induced cognitive dysfunction and brain damage in mice by modulating immune cells, reducing the number of apoptotic cells and glial cell activation in the brain, and decreasing the levels of oxidative stress and inflammatory factor expression, among which the effects of donepezil and probiotics were better than those of DHA, and the therapeutic effects of donepezil and probiotics on AD were closely related to the modulation of gut microbiome.

Cerebroprotein hydrolysate oral liquid (COL) is a neuroprotective preparation composed of various amino acids and peptides, which has beneficial effects on diverse central system diseases. However, the therapeutic effect and potential mechanism of oral COL on ischemic stroke (IS) still need to be explored. This study aims to investigate the therapeutic effects and underlying mechanisms of COL on IS in vivo and in vitro. An IS rat model was established through middle cerebral artery occlusion (MCAO) surgery, and triphenyltetrazolium chloride (TTC) staining, behavioral scoring, Evans blue leakage, enzyme-linked immunosorbent assay (ELISA) and immunofluorescence staining were performed to investigate the effects of COL on cerebral infarct size, neurological function, blood-brain barrier (BBB) and neuroinflammation in IS rats. An in vitro model of IS was established on hCMEC/D3 cells through oxygen-glucose deprivation/reperfusion (OGD/R), and cell counting kit-8 assay, reactive oxygen species (ROS) detection, scratch test and Transwell test were conducted to examine the influence of COL on cell viability, oxidative stress and migration ability. Lipidomics technology, real-time quantitative PCR and Western blot experiments were used to investigate the regulation and mechanism of COL on lipid metabolism in the brain of IS rats. All the animal experiments were approved by Ethical Committee of Animal Experiments of China Pharmaceutical University (No.2022-02-23). Our results showed that intragastric administration of COL could significantly reduce the area of cerebral infarction, improve neurological deficits, lower the levels of inflammatory factors, and protect against the blood-brain barrier damage of rats with IS. OGD/R modeling resulted in a significant decrease in the viability, an elevation in intracellular ROS levels, and a weakened cell migration ability of hCMEC/D3 cells. COL treatment could effectively protect hCMEC/D3 cells from damage caused by OGD/R. More importantly, cerebral ischemia led to significant lipid metabolism disorders in the brain of rats, and significant accumulation of intracerebral triglycerides (TAG) and ceramides (Cer) was observed in IS rats. COL was proved to significantly reverse lipid metabolism disorders in the brain of IS rats and reduce the content of cytotoxic lipid Cer by upregulating the intracerebral levels of an acid ceramidase called N-acylsphingosine amidehydrolase 1 (ASAH1). In summary, COL was proved to be a promising and effective candidate for IS treatment, which could alleviate cerebral ischemic injury by regulating abnormal lipid metabolism.

The non-alkaloid chemical constituents of dried Phellodendron chinense barks were investigated. A total of 14 phenolic compounds (1-14) were isolated from the 95% ethanol extract of Phellodendron chinense by the utilization of silica gel, medium pressure liquid chromatography, Sephadex LH-20 column chromatography, and preparative liquid chromatography. Among of the isolated compounds, isophellolactone (1) was identified as a new compound. The isolated 14 compounds were further tested the activity on α-glucosidase inhibition. The results for the first time demonstrated that quininic acid ester 3-6 and 8 exhibited good α-glucosidase inhibitory activity. Polyhydroxy hexa-membered carbon ring in quinine ester derivatives is possibly the essential group for the α-glucosidase inhibitory activity.

Eleven compounds were isolated from the ethyl acetate fraction of the 95% aqueous ethanol extract of the roots of Sophora tonkinensis by silica gel, ODS, Sephadex LH-20 column chromatography, and semi-preparative RP-HPLC. Their structures were identified as 7-hydroxy-8-isopentenylchromone (1), furo[2, 3-f]-1, 3-benzodioxole-7-carboxylic acid (2), 6-[3-(2′, 4′-dihydroxyphenyl)acryloyl]-7-hydroxy-2, 2-dimethyl-8-(3-methyl-2-butenyl)-2H-benzopyran (3), flemichapparin B (4), tectorigenin (5), genistein (6), 6-hydroxy-1, 3-benzodioxole-5-carboxylic acid (7), vanillic acid (8), protocatechuic acid (9), 2, 4-dihydroxybenzoic acid (10), and p-hydroxybenzoic acid (11) through extensive spectroscopic data (IR, UV, HR-ESI-MS, and NMR spectra). Among them, compounds 1 and 2 were new compounds. In addition, compound 3 showed significant α-glucosidase and protein tyrosine phosphatase-1B (PTP1B) inhibitory activities with IC₅₀ values of 5.595 and 0.320 μmol·L^-1, respectively.

The identification of the components absorbed in serum of platycosides in total saponins fraction of Platycodonis Radix is great significance, but there are still great challenges. In this study, 8 types of 44 primordial components from Platycodon saponins were firstly identified using the ultra-performance liquid chromatography-linear ion trap electrostatic field orbitrap high resolution mass spectrometry (UPLC-LTQ-Orbitrap-MS) equipped with the software of Compound Discoverer 3.2 and Trace finder 2.1. Then, the platycosides and their deglycosylated metabolites were used as the template molecules to construct the intestinal microbiota mediated method to identify the primary components and the prototypes in serum. As results, 57 components originating from 44 prototypes of platycosides were identified from drug-containing plasma. Those compounds consist of 12 prototypes of platycosides and 45 metabolites, while the prototypes in serum are also deglycosylated metabolites of other platycosides. The results showed that the intestinal microbiota mediated method could be applied to identify the metabolites of platycosides in total saponins fraction of Platycodonis Radix; and reveal the potential existing forms of prototypes of platycosides in plasma; In addition, it could clearly illustrate the one to many and many to one network of the prototypes and metabolites of platycosides. All animal protocols were approved by the Animal Ethics Committee of Jiangxi University of Traditional Chinese Medicine (No.JZLLSC-202100322).

Sucrose synthase plays a crucial role in the plant sugar metabolism pathway by catalyzing the production of uridine diphosphate (UDP)-glucose, which serves as a bioactive glycosyl donor for various metabolic processes. In this study, a sucrose synthase gene named CtSus was cloned from Cistanche tubulosa, a traditional Chinese medicine known for its rich content of diverse glycosides, based on transcriptome analysis results. The open reading frame of CtSus was 2 418 bp long encoding 805 amino acids. Sequence analysis revealed conserved domains associated with the plant sucrose synthase family at both the N-terminal and C-terminal regions of CtSus protein. Phylogenetic analysis demonstrated that CtSus shares a close evolutionary relationship with sucrose synthases from other plants within the same order. Functional identification of CtSus was performed through whole-cell catalysis coupling with UGT71BD1, a characterized glycosyltransferase enzyme. The results showed that the introduction of CtSus significantly enhanced the conversion rate of glycosylation catalyzed by UGT71BD1. The soluble expression of CtSus in Escherichia coli was further achieved using the pCold^TM TF expression vector. In vitro enzymatic assay indicated the activity of CtSus to catalyze the formation of UDP-glucose in the presence of sucrose and UDP. Real-time quantitative-polymerase chain reaction results showed that the expression patterns of CtSus gene in different parts of C. tubulosa and the suspension cell cultures of C. tubulosa under drought stress correlated with the accumulation patterns observed for phenylethanol glycosides, respectively. Furthermore, key amino acids and their interactions between enzyme and substrate were explored based on protein structure prediction and molecular docking results. Overall, our findings identify a sucrose synthase CtSus responsible for the supply of the active glycosyl donor UDP-glucose during the biosynthesis of glycoside products in C. tubulosa and have also provided a gene element that can be utilized in engineering strain construction for glycoside products production.

Lonicera Linn. is the largest genus of family Caprifoliaceae, which has a long history and abundant resources in China. Due to its ornamental and medicinal properties, the species of Lonicera shows outstanding economic value. However, affected by the huge demand and high price stimulation, there is a serious mixing phenomenon on the market. In this study, high-throughput sequencing technology was used to analyze the analysis of L. angustifolia Wallich ex Candolle var. myrtillus (Hook. f. & Thomson) Q. E. Yang, L. myrtillus Hook. f. et Thoms. var. cyclophylla Rehd, L. szechuanica Batal and L. tangutica Maxim to sequence and assemble their chloroplast (CP) genomes, and to conduct structural comparisons and phylogenetic studies. The results showed that the chloroplast genomes of the four species showed a typical circular tetrad structure, with a total length of 154 608-163 413 bp and a total GC content of 37.93%-38.42%. A total of 128-129 genes were annotated, including 83-84 protein-coding genes, 8 rRNA genes, and 37 tRNA genes. A total of 53-68 SSRs and 133-745 long repeats were detected by chloroplast repeat structure analysis. Phylogenetic studies showed that 21 species of Lonicera medicinal plants could be significantly clustered into one branch, among which the relatives of L. angustifolia and L. szechuanica were close, and the kinship of L. myrtillus and L. tangutica was close. This study is the first comprehensive study of the chloroplast genome and phylogenetic relationship of Loicera species, and the experimental results provide a scientific basis for revealing the genetic information, species evolution and genetic diversity of Lonicera species.