ObjectiveThis study aims to enhance of the farnesyl pyrophosphate（FPP） pool in Saccharomyces cerevisiae by heterologously expressing different farnesyl diphosphate synthases（FPSs） from various plants， thereby increasing the production of terpenoid compounds by the engineered yeast. MethodsRNA from mixed samples of roots， stems， and leaves of seven plants including Arabidopsis thaliana， Rosa rugosa， Artemisia annua， Centella asiatica， Humulus lupulus， Medicago sativa， and Panax ginseng was extracted by column chromatography and reverse transcribed into the first strand of complementary DNA（cDNA）， and based on the transcriptome data of the seven species of plants， sequence-specific primers were designed for CaFPS， RrFPS， MsFPS， HiFPS， PgFPS， AtFPS， and AaFPS， the full-length of the genes was cloned， and the genes were analyzed for bioinformatics in order to construct a pESC yeast shuttle vector. These seven plant-derived FPSs were further heterologously expressed in the previous constructed β-elemene-producing yeast， and the yield of β-elemene was indicated for their catalytic acivities. ResultsThe coding sequences of CaFPS， RrFPS， MsFPS， HiFPS， PgFPS， AtFPS， and AaFPS were all of 1 021 bp in length and encoding 301 amino acids， all of which were similarly related to the endogenous FPS-encoding gene（ERG20） in S. cerevisiae. After heterologous expression， RrFPS was identified as the most effective in catalyzing the synthesis of FPP from isopentenyl pyrophosphate（IPP） and dimethylallyl pyrophosphate（DMAPP）. Compared to the control strains， the RrFPS overexpressed yeast strains YB-1-Rr and YB-3-Rr increased the production of β-elemene by 231.25% and 189.3%， respectively. ConclusionBy comparing the functions of FPS-encoding genes from seven different plant sources， it is determined that the protein encoded by the RrFPS from R. rugosa has the best catalytic ability， which can provide key genetic elements for the construction of engineered yeast strain constructs with high terpenoid production.

Background Work-related musculoskeletal disorders (WMSDs), as one of the major occupational health issues worldwide, have shown an increasing positive rate year by year. Due to the unique demands of work, operating room nurses exhibit a higher positive rate of WMSDs compared to other occupational groups, necessitating active attention and intervention. Objective To estimate the prevalence of WMSDs among operating room nurses in tertiary hospitals, explore the characteristics and latent categories of WMSDs, and analyze the influencing factors associated with the occurrence of WMSDs. Method Using a randomized cluster sampling method, operating room nurses from nine tertiary hospitals in Urumqi were selected as study participants between December 2023 and January 2024. Data were collected through a general information questionnaire, an ergonomic questionnaire for operating room nurses, and the Chinese Musculoskeletal Disorders Questionnaire. Latent class analysis was employed to examine the patterns of WMSDs among the nurses, while chi-square test and multinomial logistic regression were utilized to analyze the influencing factors of WMSDs. Result A total of 411 valid questionnaires were collected in this survey. The positive rate of WMSDs among operating room nurses in the tertiary hospitals of Urumqi over the past year was 91.9%. The positive rates, ordered from highest to lowest by body region, were neck (79.1%), shoulders (70.3%), and lower back (68.1%). The operating room nurses were categorized into three distinct groups by latent class analysis: multi-site pain group, neck-shoulder-back pain group, and neck and lower back pain group. The results of the multinomial logistic regression models revealed that gender, job strain level, ergonomic load level in the operating room, and exposure to cold or drafty working conditions or not were significant influencing factors for reporting WMSDs among operating room nurses. Specifically, having less than 5 years of work experience, low ergonomic load level, low job strain, and moderate job strain were identified as protective factors against WMSDs. Conversely, exposure to cold or drafty working environments and being female were identified as risk factors for WMSDs. The logistic regression models also indicated that compared to the neck-lower back pain group, the neck-shoulder-back pain group had a higher probability of reporting low job strain (OR=0.168, 95%CI: 0.029, 0.968) and being female (OR=4.847, 95%CI: 2.506, 9.378). In contrast, when comparing to the neck-lower back pain group, the multi-site pain group had a higher probability of reporting, low-level ergonomic workload (OR=0.079, 95%CI: 0.015, 0.412), low job strain (OR=0.019, 95%CI: 0.002, 0.145), moderate job strain (OR=0.080, 95%CI: 0.016, 0.401), high job strain (OR=0.132, 95%CI: 0.027, 0.647), less than 5 years of work experience (OR=0.173, 95%CI: 0.044, 0.683), being female (OR=2.424, 95%CI: 1.130, 5.200), and exposure to cold or drafty working environments (OR=3.277, 95%CI: 1.657, 6.481). Conclusion The positive rate WMSDs among operating room nurses in tertiary hospitals is notably high in Urumqi, with distinct co-occurrence characteristics observed within the population. To mitigate the risk of WMSDs, it is essential to implement targeted health education and prevention training programs tailored to different patterns of WMSDs. Additionally, improving working conditions, optimizing human resource allocation , and other proactive measures should be undertaken. These efforts will effectively reduce the incidence of WMSDs among operating room nurses and safeguard their occupational health.

Adipose tissue is a critical energy reservoir in animals and humans, with multifaceted roles in endocrine regulation, immune response, and providing mechanical protection. Based on anatomical location and functional characteristics, adipose tissue can be categorized into distinct types, including white adipose tissue (WAT), brown adipose tissue (BAT), beige adipose tissue, and pink adipose tissue. Traditionally, adipose tissue research has centered on its morphological and functional properties as a whole. However, with the advent of single-cell transcriptomics, a new level of complexity in adipose tissue has been unveiled, showing that even under identical conditions, cells of the same type may exhibit significant variation in morphology, structure, function, and gene expression——phenomena collectively referred to as cellular heterogeneity. Single-cell transcriptomics, including techniques like single-cell RNA sequencing (scRNA-seq) and single-nucleus RNA sequencing (snRNA-seq), enables in-depth analysis of the diversity and heterogeneity of adipocytes at the single-cell level. This high-resolution approach has not only deepened our understanding of adipocyte functionality but also facilitated the discovery of previously unidentified cell types and gene expression patterns that may play key roles in adipose tissue function. This review delves into the latest advances in the application of single-cell transcriptomics in elucidating the heterogeneity and diversity within adipose tissue, highlighting how these findings have redefined the understanding of cell subpopulations within different adipose depots. Moreover, the review explores how single-cell transcriptomic technologies have enabled the study of cellular communication pathways and differentiation trajectories among adipose cell subgroups. By mapping these interactions and differentiation processes, researchers gain insights into how distinct cellular subpopulations coordinate within adipose tissues, which is crucial for maintaining tissue homeostasis and function. Understanding these mechanisms is essential, as dysregulation in adipose cell interactions and differentiation underlies a range of metabolic disorders, including obesity and diabetes mellitus type 2. Furthermore, single-cell transcriptomics holds promising implications for identifying therapeutic targets; by pinpointing specific cell types and gene pathways involved in adipose tissue dysfunction, these technologies pave the way for developing targeted interventions aimed at modulating specific adipose subpopulations. In summary, this review provides a comprehensive analysis of the role of single-cell transcriptomic technologies in uncovering the heterogeneity and functional diversity of adipose tissues.

Objective: To investigate the mechanism of in alleviating colonic mucosal inflammation in ten-eleven translocation (TET) protein 2 gene knockout (TET2-/-) mice with ulcerative colitis (UC) by regulating DNA methyltransferase (DNMT) and DNA hydroxymethylase. Methods: Male specific pathogen-free (SPF) grade C57BL/6J wild-type (WT) mice (n = 8) and TET2-/- mice (n = 20) were used to establish UC models by freely drinking 3% dextran sulfate sodium solution for 7 d. After UC model validation through histopathological examination in two mice from each type, the remaining mice were divided into four groups (n = 6 in each group): WT model (WT + UC), TET2-/- model (TET2-/- + UC), TET2-/- mild moxibustion (TET2-/- + MM), and TET2-/- electroacupuncture (TET2-/- + EA) groups. TET2-/- + MM group received mild moxibustion on Tianshu (ST25) and Qihai (CV6) for 10 min daily for 7 d. The TET2-/- + EA group also applied electroacupuncture (1 mA, 2/100 Hz) at the same acupoints for 10 min daily for 7 d. The disease activity index (DAI) scores of each group of mice were accessed daily. The colon lengths of mice in groups were measured following intervention. The pathological changes in the colon tissues were observed with hematoxylin and eosin (HE) staining. The concentrations of interleukin (IL)-6, C-C motif chemokine 17 (CCL17), and C-X-C motif chemokine ligand 10 (CXCL10) in serum were detected by enzyme-linked immunosorbent assay (ELISA). The expression of DNMT proteins (DNMT1, DNMT3A, and DNMT3B) in the colon tissues was detected by immunohistochemistry. The expression of 5-methylcytosine (5-mC), 5-hydroxymethylcytosine (5-hmC), histone deacetylase 2 (HDAC2), and DNA hydroxymethylase family proteins (TET 1 and TET3) was detected using immunofluorescence, which also determined the co-localization of TET1 and IL-6 protein. Results: Compared with WT + UC group, TET2-/- + UC group exhibited significantly higher DAI scores and shorter colon lengths (P < 0.01). Both mild moxibustion and electroacupuncture significantly decreased DAI scores and ameliorated colon shortening in TET2-/- mice (P < 0.001). Histopathological scores of TET2-/- + UC mice were significantly higher than those of WT + UC group (P < 0.001) and were significantly reduced after both mild moxibustion and electroacupuncture interventions (P < 0.001). Serum levels of IL-6, CCL17, and CXCL10 were significantly elevated in TET2-/- + UC group compared with WT + UC group (P < 0.001). Mild moxibustion significantly reduced IL-6, CCL17, and CXCL10 levels (P < 0.001, P < 0.001, and P < 0.01, respectively), while electroacupuncture also significantly reduced IL-6, CCL17, and CXCL10 levels (P < 0.05, P < 0.01, and P < 0.01, respectively). TET2-/- + UC mice showed increased expression levels of DNMT1, DNMT3A , DNMT3B, and 5-mC (P < 0.05, P < 0.01 and P < 0.001, respectively), with decreased expression levels of TET1, TET3, 5-hmC, and HDAC2 (P < 0.001). Mild moxibustion significantly reduced DNMT1, DNMT3B, and 5-mC levels (P < 0.05, P < 0.01, and P < 0.001, respectively), while increasing expression levels of TET1, TET3, 5-hmC, and HDAC2 (P < 0.001, P < 0.001, P < 0.05, and P < 0.001, respectively). Electroacupuncture significantly decreased 5-mC and DNMT3B levels (P < 0.001 and P < 0.01, respectively) and increased 5-hmC and HDAC2 levels (P < 0.05 and P < 0.001, respectively), but did not significantly affect TET1 and TET3 expression (P > 0.05). Compared with TET2-/- + MM group, TET2-/- + EA group showed significantly higher 5-mC expression (P < 0.001). TET2-/- + UC group exhibited markedly increased IL-6 expression and higher co-localization of TET1 and IL-6 in mucosal epithelium, whereas minimal IL-6 expression was observed in the other groups. Conclusion Mild moxibustion and electroacupuncture significantly ameliorate colonic inflammation exacerbated by TET2 deficiency in UC mice via epigenetic modulation. Distinct mechanisms exist between the two interventions: mild moxibustion regulates both DNMT and hydroxymethylase, whereas electroacupuncture primarily affects DNMT.

BACKGROUND:Extracellular vesicles are secreted into the extracellular milieu by a wide range of cell types,including tumor cells,under different physiological and pathophysiological conditions,where a wide range of biological signals and cell-to-cell signaling exists.Tumor-derived extracellular vesicles may exacerbate cancer progression,survival,invasion,and promote angiogenesis. OBJECTIVE:To review the research progress of extracellular vesicles in the diagnosis and treatment of oral squamous cell carcinoma. METHODS:Literature search was performed by the first author in PubMed,WanFang,CNKI and other databases with the keywords"EVs,oral squamous cell carcinoma,diagnosis and treatment,biopsy,tissue engineering"in Chinese and English.Finally,63 articles were included for analysis. RESULTS AND CONCLUSION:(1)In oral squamous carcinoma saliva biopsies,extracellular vesicles play a crucial role in the progression of oral squamous cell carcinoma by acting as an information transfer tool between tumor cells and the surrounding microenvironment,carrying a wide range of biomolecules including soluble proteins,lipids,DNA,and RNA.These tiny vesicles not only play a key role in tumor growth and spread,but also provide important information about the biological properties of the tumor.(2)Saliva biopsy,as a non-invasive diagnostic method,can open up new possibilities for early diagnosis and targeted treatment of oral squamous cell carcinoma by analyzing the extracellular vesicles therein.(3)It has been found that bioactive molecules,such as microRNAs(miRNAs)and specific proteins,contained within extracellular vesicles can serve as biomarkers for oral squamous carcinoma and improve the accuracy of early diagnosis.Specific proteins in extracellular vesicles such as EHD2,CAVIN1,PF4V1,and CXCL7 show potential as novel predictive biomarkers.(4)In addition,this paper highlights the potential application of extracellular vesicles in the treatment of oral squamous carcinoma.Through engineering modifications,extracellular vesicles can serve as a new generation of nanoscale drug delivery systems to enhance the efficiency and specificity of targeted tumor therapy.(5)Future studies will further explore the effect and mechanism of extracellular vesicles in oral squamous cell carcinoma,which is expected to improve patients'survival and quality of life.

ObjectiveThis paper aims to investigate the potential molecular biological mechanism of Buyang Huanwu Tongfeng decoction in treating hyperuricemia and gouty arthritis by network pharmacology and molecular docking technology and preliminarily verify the mechanism through animal experiments. MethodsThe active ingredients and targets in the Buyang Huanwu Tongfeng decoction were obtained by the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform （TCMSP） and ETCM databases. The DisGeNET and GeneCards databases were utilized to acquire disease targets associated with hyperuricemia and gouty arthritis. These disease targets were then intersected with drug targets to identify key targets. The R language ClusterProfiler package and Python were employed for conducting gene ontology（GO） enrichment analysis and Kyoto encyclopedia of genes and genomes（KEGG） enrichment analysis. The regulatory network diagram of the drug-key target-function-pathway was visualized using Cytoscape 3.9.1 software， and the protein-protein interaction （PPI） network for key targets was depicted. Finally， the hub gene was determined through topological analysis. Auto Dock， PyMOL， and other software were used for molecular docking to explore the possible therapeutic mechanism of Buyang Huanwu Tongfeng decoction for hyperuricemia and gouty arthritis. In animal experiments， a composite rat model of hyperuricemia induced by intraperitoneal injection of oteracil potassium combined with gouty arthritis induced by the modified Coderre method was established. Through hematoxylin-eosin（HE） staining， uric acid test， enzyme linked immunosorbent assay（ELISA）， Western blot， and real-time polymerase chain reaction（Real-time PCR）， the molecular mechanism and key targets of Buyang Huanwu Tongfeng decoction for treating hyperuricemia and gouty arthritis were observed. ResultsAfter screening and removing duplicate values， 76 active ingredients and 15 key targets were finally obtained. GO enrichment analysis yielded that the treatment of hyperuricemia and gouty arthritis with Buyang Huanwu Tongfeng decoction was significantly associated with acute inflammatory response， astrocyte activation， regulation of interleukin （IL）-8 production， nuclear receptor activity， and binding of growth factor receptor. KEGG pathway enrichment analysis obtained that the key target genes were significantly associated with the IL-17 signaling pathway， advanced glycosylation end/receptor of advanced glycation endproducts（AGE/RAGE） signaling pathway， anti-inflammatory， and other pathways. PPI network indicated that albumin（ALB）， peroxisome proliferator-activated receptor-γ （PPAR-γ）， IL-6， IL-1β， and C-reactive protein（CRP） were the key protein targets. The molecular docking results showed that ALB had the strongest binding force with beta-carotene （β-carotene）. Biochemical results showed that blood uric acid decreased in the Buyang Huanwu Tongfeng decoction groups. HE staining results showed that the low-dose （7.76 g·kg^-1·d^-1）， medium-dose （15.53 g·kg^-1·d^-1）， and high-dose （31.05 g·kg^-1·d^-1） groups of Buyang Huanwu Tongfeng decoction had different degrees of remission， and the remission of the high-dose group was the most obvious. Fibroblastic tissue hyperplasia in synovial joints accompanied with inflammatory cell infiltration， as well as inflammatory cell infiltration in renal tissue of the high-dose group was significantly reduced， followed by the medium-dose and low-dose groups， and the expression of ALB， PPAR-γ， IL-6， IL-1β， and CRP was down-regulated to different degrees. ConclusionBy regulating the targets such as ALB， PPAR-γ， IL-6， IL-1β， and CRP， inhibiting the PPAR-γ/nuclear transcription factor （NF）-κB pathway， and reducing AGEs/RAGE-mediated inflammation， Buyang Huanwu Tongfeng decoction exerts anti-inflammatory and analgesic effects and activates blood circulation and diuresis in the treatment of hyperuricemia and gouty arthritis.

Prescription optimization is a crucial aspect in the study of traditional Chinese medicine （TCM） compounds. In recent years， the introduction of mathematical methods， data mining techniques， and artificial neural networks has provided new tools for elucidating the compatibility rules of TCM compounds. The study of TCM compounds involves numerous variables， including the proportions of different herbs， the specific extraction parts of each ingredient， and the interactions among multiple components. These factors together create a complex nonlinear dose-effect relationship. In this context， it is essential to identify methods that suit the characteristics of TCM compounds and can leverage their advantages for effective application in new drug development. This paper provided a comprehensive review of the cutting-edge optimization experimental design methods applied in recent studies of TCM compound compatibilities. The key technical issues， such as the optimization of source material selection， dosage optimization of compatible herbs， and multi-objective optimization indicators， were discussed. Furthermore， the evaluation methods for component effects were summarized during the optimization process， so as to provide scientific and practical foundations for innovative research in TCM and the development of new drugs based on TCM compounds.

Guided by the concept of quality by design(QbD), this study optimizes the calcination and quenching process of calcined Magnetitum and establishes the XRD characteristic spectra of calcined Magnetitum, providing a scientific basis for the formulation of quality standards. Based on the processing methods and quality requirements of Magnetitum in the Chinese Pharmacopoeia, the critical process parameters(CPPs) identified were calcination temperature, calcination time, particle size, laying thickness, and the number of vinegar quenching cycles. The critical quality attributes(CQAs) included Fe mass fraction, Fe~(2+) dissolution, and surface color. The weight coefficients were determined by combining Analytic Hierarchy Process(AHP) and the criteria importance though intercrieria correlation(CRITIC) method, and the calcination process was optimized using orthogonal experimentation. Surface color was selected as a CQA, and based on the principle of color value, the surface color of calcined Magnetitum was objectively quantified. The vinegar quenching process was then optimized to determine the best processing conditions. X-ray diffraction(XRD) was used to establish the characteristic spectra of calcined Magnetitum, and methods such as similarity evaluation, cluster analysis, and orthogonal partial least squares-discriminant analysis(OPLS-DA) were used to evaluate the quality of the spectra. The optimized calcined Magnetitum preparation process was found to be calcination at 750 ℃ for 1 h, with a laying thickness of 4 cm, a particle size of 0.4-0.8 cm, and one vinegar quenching cycle(Magnetitum-vinegar ratio 10∶3), which was stable and feasible. The XRD characteristic spectra analysis method, featuring 9 common peaks as fingerprint information, was established. The average correlation coefficient ranged from 0.839 5-0.988 1, and the average angle cosine ranged from 0.914 4 to 0.995 6, indicating good similarity. Cluster analysis results showed that Magnetitum and calcined Magnetitum could be grouped together, with similar compositions. OPLS-DA discriminant analysis identified three key characteristic peaks, with Fe_2O_3 being the distinguishing component between the two. The final optimized processing method is stable and feasible, and the XRD characteristic spectra of calcined Magnetitum was initially established, providing a reference for subsequent quality control and the formulation of quality standards for calcined Magnetitum.
X-Ray Diffraction/methods* ; Drugs, Chinese Herbal/chemistry* ; Quality Control ; Particle Size

This study explores the role and underlying molecular mechanisms of fucoidan sulfate(FPS) in regulating heme oxygenase-1(Hmox1)-mediated ferroptosis to ameliorate myocardial injury in diabetic cardiomyopathy(DCM) through in vivo and in vitro experiments and network pharmacology analysis. In vivo, a DCM rat model was established using a combination of "high-fat diet feeding + two low-dose streptozotocin(STZ) intraperitoneal injections". The rats were randomly divided into four groups: normal, model, FPS, and dapagliflozin(Dapa) groups. In vitro, a cellular model was created by inducing rat cardiomyocytes(H9c2 cells) with high glucose(HG), using zinc protoporphyrin(ZnPP), an Hmox1 inhibitor, as the positive control. An automatic biochemical analyzer was used to measure blood glucose(BG), serum aspartate aminotransferase(AST), serum lactate dehydrogenase(LDH), and serum creatine kinase-MB(CK-MB) levels. Echocardiography was used to assess rat cardiac function, including ejection fraction(EF) and fractional shortening(FS). Pathological staining was performed to observe myocardial morphology and fibrotic characteristics. DCFH-DA fluorescence probe was used to detect reactive oxygen species(ROS) levels in myocardial tissue. Specific assay kits were used to measure serum brain natriuretic peptide(BNP), myocardial Fe~(2+), and malondialdehyde(MDA) levels. Western blot(WB) was used to detect the expression levels of myosin heavy chain 7B(MYH7B), natriuretic peptide A(NPPA), collagens type Ⅰ(Col-Ⅰ), α-smooth muscle actin(α-SMA), ferritin heavy chain 1(FTH1), solute carrier family 7 member 11(SLC7A11), glutathione peroxidase 4(GPX4), 4-hydroxy-2-nonenal(4-HNE), and Hmox1. Immunohistochemistry(IHC) was used to examine Hmox1 protein expression patterns. FerroOrange and Highly Sensitive DCFH-DA fluorescence probes were used to detect intracellular Fe~(2+) and ROS levels. Transmission electron microscopy was used to observe changes in mitochondrial morphology. In network pharmacology, FPS targets were identified through the PubChem database and PharmMapper platform. DCM-related targets were integrated from OMIM, GeneCards, and DisGeNET databases, while ferroptosis-related targets were obtained from the FerrDb database. A protein-protein interaction(PPI) network was constructed for the intersection of these targets using STRING 11.0, and core targets were screened with Cytoscape 3.9.0. Molecular docking analysis was conducted using AutoDock and PyMOL 2.5. In vivo results showed that FPS significantly reduced AST, LDH, CK-MB, and BNP levels in DCM model rats, improved cardiac function, decreased the expression of myocardial injury proteins(MYH7B, NPPA, Col-Ⅰ, and α-SMA), alleviated myocardial hypertrophy and fibrosis, and reduced Fe~(2+), ROS, and MDA levels in myocardial tissue. Furthermore, FPS regulated the expression of ferroptosis-related markers(Hmox1, FTH1, SLC7A11, GPX4, and 4-HNE) to varying degrees. Network pharmacology results revealed 313 potential targets for FPS, 1 125 targets for DCM, and 14 common targets among FPS, DCM, and FerrDb. Hmox1 was identified as a key target, with FPS showing high docking activity with Hmox1. In vitro results demonstrated that FPS restored the expression levels of ferroptosis-related proteins, reduced intracellular Fe~(2+) and ROS levels, and alleviated mitochondrial structural damage in cardiomyocytes. In conclusion, FPS improves myocardial injury in DCM, with its underlying mechanism potentially involving the regulation of Hmox1 to inhibit ferroptosis. This study provides pharmacological evidence supporting the therapeutic potential of FPS for DCM-induced myocardial injury.
Animals ; Ferroptosis/drug effects* ; Rats ; Diabetic Cardiomyopathies/physiopathology* ; Male ; Rats, Sprague-Dawley ; Polysaccharides/pharmacology* ; Heme Oxygenase-1/genetics* ; Myocytes, Cardiac/metabolism* ; Myocardium/pathology* ; Humans ; Cell Line ; Heme Oxygenase (Decyclizing)

Many triterpenoid compounds have been successfully heterologously synthesized in Saccharomyces cerevisiae. To increase the yield of triterpenoids, various metabolic engineering strategies have been developed. One commonly applied strategy is to enhance the supply of precursors, which has been widely used by researchers. Squalene, as a precursor to triterpenoid biosynthesis, plays a crucial role in the synthesis of these compounds. This study primarily investigates the effect of different squalene levels in chassis strains on the synthesis of triterpenoids(oleanolic acid and ursolic acid), and the underlying mechanisms are further explored using real-time quantitative PCR(qPCR) analysis. The results demonstrate that the chassis strain CB-9-5, which produces high levels of squalene, inhibits the synthesis of oleanolic acid and ursolic acid. In contrast, chassis strains with moderate to low squalene production, such as Y8-1 and CNPK, are more conducive to the synthesis of oleanolic acid and ursolic acid. The qPCR analysis reveals that the expression levels of ERG1, βAS, and CrCYP716A154 in the oleanolic acid-producing strain CB-OA are significantly lower than those in the control strains C-OA and Y-OA, suggesting that high squalene production in the chassis strains suppresses the transcription of certain genes, leading to a reduced yield of triterpenoids. Our findings indicate that when constructing S. cerevisiae strains for triterpenoid production, chassis strains with high squalene content may suppress the expression of certain genes, ultimately lowering their production, whereas chassis strains with moderate squalene levels are more favorable for triterpenoid biosynthesis.
Squalene/analysis* ; Saccharomyces cerevisiae/genetics* ; Triterpenes/metabolism* ; Metabolic Engineering ; Oleanolic Acid/biosynthesis* ; Ursolic Acid