T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

Existing studies have underscored the pivotal role of N-acetyltransferase 10 (NAT10) in various cancers. However, the outcomes of protein-protein interactions between NAT10 and its protein partners in head and neck squamous cell carcinoma (HNSCC) remain unexplored. In this study, we identified a significant upregulation of RNA-binding protein with serine-rich domain 1 (RNPS1) in HNSCC, where RNPS1 inhibits the ubiquitination degradation of NAT10 by E3 ubiquitin ligase, zinc finger SWIM domain-containing protein 6 (ZSWIM6), through direct protein interaction, thereby promoting high NAT10 expression in HNSCC. This upregulated NAT10 stability mediates the enhancement of specific tRNA ac⁴C modifications, subsequently boosting the translation process of genes involved in pathways such as IL-6 signaling, IL-8 signaling, and PTEN signaling that play roles in regulating HNSCC malignant progression, ultimately influencing the survival and prognosis of HNSCC patients. Additionally, we pioneered the development of TRMC-seq, leading to the discovery of novel tRNA-ac⁴C modification sites, thereby providing a potent sequencing tool for tRNA-ac⁴C research. Our findings expand the repertoire of tRNA ac⁴C modifications and identify a role of tRNA ac⁴C in the regulation of mRNA translation in HNSCC.
Humans ; DNA-Binding Proteins ; Head and Neck Neoplasms/genetics* ; N-Terminal Acetyltransferases ; RNA, Transfer ; Serine ; Signal Transduction ; Squamous Cell Carcinoma of Head and Neck

Cellulose synthase (CesA), one of the key enzymes in the biosynthesis of cellulose in plants, plays an important role in plant growth and plant resistance. In this study, a total of 21 AsCesA genes from Aquilaria sinensis were systematically identified and the physico-chemical characteristics were analyzed based on genome database and bioinformatical methods. The phylogenetic tree was constructed and the gene location on chromosome, cis-acting elements in the 2 000 basepairs upstream regulatory regions and conservative motifs were analyzed. The AsCesA proteins were mainly located on the plasma membrane. The number of amino acids of the proteins ranged from 390 to 1 261. The isoelectric point distributed from 5.67 to 8.86. All of the 21 AsCesA proteins possessed the transmembrane domains, the number of which was from 6 to 8. The genes were classified into 3 groups according to the phylogenetic relationship. Obvious differences were observed in motif composition in genes from different groups. However, motif2, motif6, motif7 and motif10 were observed in all of AsCesA proteins. Analysis of cis-acting elements indicated that AsCesA genes family has cis-acting elements related to plant hormones, abiotic stresses, and biological processes. Seven AsCesA genes with differential expression were selected according to the calli transcriptome data induced by NaCl at different times and their expression levels under different abiotic stresses were analyzed by quantitative real-time PCR. The results indicated that salt, low temperature, drought, and heavy metal stresses could affect the expression level of AsCesA genes, and the abundance of AsCesA1, AsCesA3 and AsCesA20 showed a significant change, implying their potential important roles to the abiotic stresses. The accumulation pattern of cellulose content under different abiotic stresses was similar to the expression trend of AsCesA genes. Our results provide valuable insights into the role of cellulose synthase in A.sinensis in plant defense.

ObjectiveTo observe the effect of Banxia Xiexintang （BXT） on the proliferation of human gastric cancer HGC-27， MKN-45， and AGS cells and its mechanism. MethodCell counting kit-8 （CCK-8） was used to detect the effects of different concentrations of BXT-containing serum （5%， 10%， and 20%） on the proliferation of HGC-27， MKN-45， and AGS cells. A mitochondrial membrane potential probe （TMRE） was used to detect the expression of mitochondrial membrane potential in cells. A kit was used to detect iron ion （Fe²⁺） content， lipid peroxide （LPO）， and superoxide dismutase （SOD） activity. Western blot was used to detect the protein expression levels of glycogen synthase3β （GSK3β）， phosphorylated GSK3β （p-GSK3β）， nuclear factor E₂ related factor 2 （Nrf2）， and glutathione peroxidase 4 （GPX4）. The real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of member 11 of the cystine/glutamic acid reverse transporter solute vector family 7 （SLC7A11）， member 2 of the heavy chain solute vector family 3 （SLC3A2）， transferrin receptor 3 （TFRC）， and tumor protein （TP）53. ResultCCK-8 results showed that BXT and capecitabine could significantly reduce the survival rate of three kinds of gastric cancer cells after treatment with drug-containing serum for 24 h （P<0.01）. After 48 h of intervention with drug-containing serum， the survival rate of three kinds of gastric cancer cells was significantly decreased in both the capecitabine group and the BXT group compared with the blank group. The BXT group was dose-dependent， with 20% BXT having the most significant effect （P<0.01）. In terms of biochemical indicators of ferroptosis， compared with the blank group， BXT and capecitabine significantly decreased the expression of mitochondrial membrane potential （P<0.01） and SOD activity （P<0.01） and significantly increased the contents of LPO and Fe²⁺ （P<0.01）， so as to improve the sensitivity of gastric cancer cells to ferroptosis. In terms of the Nrf2/GPX4 pathway， compared with the blank group， the BXT group could reduce the protein expressions of p-GSK3β， Nrf2， and GPX4 （P<0.01） in gastric cancer cells and increase mRNA expressions of SLC7A11 and SLC3A2 （P<0.05）. It could also increase the protein expression of GSK3β （P<0.01） and mRNA expression of TP53 and TFRC （P<0.05， P<0.01） in gastric cancer cells. Inhibition of the Nrf2/GPX4 pathway induces ferroptosis in gastric cancer cells. Compared with the capecitabine group， the 20% BXT group showed a more obvious effect. ConclusionBanxia Xiexintang can induce ferroptosis in gastric cancer cells HGC-27， MKN-45， and AGS by inhibiting the Nrf2/GPX4 pathway.

Objective To provide reference for the subsequent clinical application of WBV,based on the impacts of whole body vibration(WBV)with different frequencies on gross motor function and walking function in children with dyskinetic cerebral palsy.Methods 60 children aged 6～12 with dyskinetic cerebral palsy,who had been treated at the department of rehabilitation medicine in the Affiliated Southwest Medical University from October 2021 to November 2022,were selected.They were randomly divided into a control group(n = 20),(25±5)Hz group(n = 20),and(35±5)Hz group(n = 20).All the three groups received conventional rehabilitation,while the(25±5)Hz group received additional WBV with(25±5)Hz and the(35±5)Hz group received WBV with(35±5)Hz.They were treated for eight weeks.The scores on D and E domains of GMFM-88,TUGT,the score on Berg Balance Scale,and footprint analysis were used for assessment of the efficacy after treatment.Results As compared with the baselines,the scores were improved in the three groups after treatment(P＜0.001).BBS(F = 12.502),TUGT(F = 8.211),scores on D and E domains of GMFM-88(F = 12.802 and 8.505),stride length(F = 12.279),1MWT distance(F = 12.619),and step width(F = 13.582)were better in the(35±5)Hz group than in the(25±5)Hz group and the control group(P＜0.05 and P＜0.01);and the efficacy was better in the(25±5)Hz group than in the control group,the difference was statistically significant(P＜0.05 and P＜0.01).Conclusion WBV can improve trunk control,lower limb gross motor function,and walking function in children with involuntary motor type cerebral palsy.(35±5)Hz is better than(25±5)Hz for the efficacy of WBV.

BACKGROUND:Several studies have found that the total flavonoids of rhizome drynariae can promote neovascularization in the induced membrane,improve the biological properties of the induced membrane,and accelerate bone remodeling in the induced membrane,but the related molecular mechanisms still need to be further explored. OBJECTIVE:To explore the effect of total flavonoids of rhizome drynariae on bone remodeling in rat femoral Masquelet-induced membrane model by regulating H-type blood vessels. METHODS:Thirty-six male Sprague-Dawley rats were stratified by body mass and then randomly divided into blank group,model group and traditional Chinese medicine group,with 12 rats in each group.A 4-mm femoral bone defect model was established in all the rats.Bone defects in the model group and traditional Chinese medicine group were filled with polymethylmethacrylate bone cement.At 6 weeks after modeling,the tail bone of the rats was implanted in the blank group,as well as in the other two groups after removal of bone cement.The traditional Chinese medicine group was given 157.5 mg/kg per day of total flavonoids of rhizome drynariae at 3 days after bone implantation,while the model and blank groups were given the same amount of saline by gavage until the 8th week after bone implantation.Bone graft samples were taken for relevant testing at 8 weeks after implantation. RESULTS AND CONCLUSION:X-ray films showed that in the blank group,the fracture line in the defect area was clear,and only a small amount of bone callus formed;in the model group,the bone defect area still existed,where discontinuous cortical bone was visible;in the traditional Chinese medicine group,the defect area was filled with newborn bone tissues,the bone marrow cavity and part of the cortical bone formed,and the fracture line disappeared.Micro-CT scans showed that the amount of new bone in the defect area was low in the blank group,the number of bone trabeculae in the defect area was significantly increased in the model group,and a large amount of new bone tissue was filled in the bone defect area in the traditional Chinese medicine group.Hematoxylin-eosin staining results showed that in the blank group,only a small amount of new bone formed in the defect area and the quality of osteogenesis was poor;in the model group,there was more new bone tissue in the defect area,but some fibrous connective tissues were interspersed within the bone tissue;and in the traditional Chinese medicine group,a large amount of new bone formed in the defect area and the quality of osteogenesis was the best.CD31/Emcn immunofluorescence double-labeling staining results showed that the number of H-type blood vessels in the newborn bone tissue in the bone defect area of the blank group was sparse and sparsely distributed;compared with the blank group,there were more H-type blood vessels in the bone tissue in the bone defect area of the model group,and the blood vessels were distributed in relatively regular strips;the number of H-type blood vessels in the bone defect area of the traditional Chinese medicine group was the highest and the blood vessels were densely distributed.To conclude,the total flavonoids of rhizoma drynariae can upregulate the expression of H-type blood vessels to enhance the angiogenic-osteogenic effect,improve the osteogenic efficiency of the rat femoral Masquelet induced membrane model,and promote bone remodeling.

This article mainly elaborated the acupuncture and moxibustion treatment scheme of"eighteen needles for reproduction"based on Professor You Zhaoling's reproductive axis theory of"heart-kidney-Chong Ren-uterus".The"eighteen needles for reproduction"aims to regulate the disordered reproductive axis in gynecological reproductive diseases.It selects the acupoints on the main viscera and meridians of the reproductive axis as the main acupoints,and the acupoints regulating the qi and blood of the related viscera as the matching acupoints.Through specific manipulation,it can regulate the qi and blood,dredge the meridians,and treat the viscera,so as to nourish the essence and help pregnancy,and provide ideas and reference for the treatment of gynecological reproductive diseases with acupuncture and moxibustion.

Objective:To compare the antiplatelet effects of vicagrel and clopidogrel in patients with different cytochrome P450 (CYP) 2C19 genotypes.Methods:This is a post-hoc analysis of a phase Ⅱ clinical trial of vicagrel, which included patients with coronary heart disease who underwent percutaneous coronary intervention from August 2018 to June 2019 in 18 centers. Patients were categorized based on the presence of CYP 2C19 *2 or *3 loss-of-function (LOF) alleles into LOF carrier group ( n=111) and non-LOF carrier group ( n=90). Each group included patients received vicagrel 5 mg, 6 mg, 7.5 mg, or clopidogrel 75 mg for 28 days per study protocol. P2Y 12 reaction units (PRU) were measured using VerifyNow at baseline, 6 to 8 hours after loading dose, 7 to 10 days after randomization, and 28 days after randomization and the percentage inhibition of platelet aggregation (%IPA) was calculated. The primary endpoint was %IPA on day 28. Within the patients from the General Hospital of Northern Theater Command, 8 to 12 patients in each study arms were enrolled in a prespecified pharmacokinetic sub-study, measuring the time to reach maximum plasma concentration (T max), peak plasma concentration (C max), and area under the plasma concentration-time curve (AUC). Results:Among 201 patients, the age was (58.8±8.5) years, and 139 (69.2%) were male. In non-LOF carriers, there was no significant differences in PRU values and %IPA between the vicagrel 5 mg, 6 mg, 7 mg, and clopidogrel groups at all time points (all P>0.05). In LOF carriers, %IPA was significantly higher in the vicagrel-treated groups than in the clopidogrel group at 6-8 hours after loading dose (22.9 (14.2, 31.5)% vs. 19.8 (11.0, 28.6)% vs. 29.5 (20.9, 38.0)% vs. 12.9 (3.9, 21.9)%, P=0.038) and 7-10 days after randomization (22.4 (14.2, 30.5)% vs. 34.4 (26.1, 42.6)% vs. 39.8 (31.8, 47.9)% vs. 24.7 (16.3, 33.2)%, P=0.001), with a trend towards higher %IPA in the vicagrel-treated groups at day 28 (30.4 (21.3, 39.6)% vs. 36.5 (27.2, 45.7)% vs. 40.8 (31.8, 49.8)% vs. 30.7(21.2, 40.2)%, P=0.056). Pharmacokinetic results of 35 patients showed that the C max and AUC of the active metabolite M15-2 of vicagrel was similar to that of clopidogrel in non-LOF carriers, but AUC between vicagrel 5 mg, 6 mg, 7 mg and clopidogrel were significantly different in LOF carriers ((5.6±0.6) h·μg -1·L -1 vs. (6.8±2.7) h·μg -1·L -1 vs. (9.2±3.3) h·μg -1·L -1 vs. (4.2±1.9) h·μg -1·ml -1, P=0.020). Conclusion:Vicagrel and clopidogrel have similar antiplatelet effects in non-LOF carriers, but vicagrel exhibits superior antiplatelet effects in LOF carriers.

Background: Twenty-four-hour urinary free cortisol (UFC) measurement is the initial diagnostic test for Cushing’s syndrome (CS). We compared UFC determination by both direct and extraction immunoassays using Abbott Architect, Siemens Atellica Solution, and Beckman DxI800 with liquid chromatography-tandem mass spectrometry (LC-MS/MS). In addition, we evaluated the value of 24-hr UFC measured by six methods for diagnosing CS. Methods: Residual 24-hr urine samples of 94 CS and 246 non-CS patients were collected.A laboratory-developed LC-MS/MS method was used as reference. UFC was measured by direct assays (D) using Abbott, Siemens, and Beckman platforms and by extraction assays (E) using Siemens and Beckman platforms. Method was compared using Passing–Bablok regression and Bland–Altman plot analyses. Cut-off values for the six assays and corresponding sensitivities and specificities were calculated by ROC analysis. Results: Abbott-D, Beckman-E, Siemens-E, and Siemens-D showed strong correlations with LC-MS/MS (Spearman coefficient r = 0.965, 0.922, 0.922, and 0.897, respectively), while Beckman-D showed weaker correlation (r = 0.755). All immunoassays showed proportionally positive bias. The areas under the curve were 0.975 for Abbott-D, 0.972 for LCMS/MS, 0.966 for Siemens-E, 0.948 for Siemens-D, 0.955 for Beckman-E, and 0.877 for Beckman-D. The cut-off values varied significantly (154.8–1,321.5 nmol/24 hrs). Assay sensitivity and specificity ranged from 76.1% to 93.2% and from 93.0% to 97.1%, respectively. Conclusions Commercially available immunoassays for measuring UFC show different levels of analytical consistency compared to LC-MS/MS. Abbott-D, Siemens-E, and Beckman-E have high diagnostic accuracy for CS.

Existing studies have underscored the pivotal role of N-acetyltransferase 10(NAT10)in various cancers.However,the outcomes of protein-protein interactions between NAT10 and its protein partners in head and neck squamous cell carcinoma(HNSCC)remain unexplored.In this study,we identified a significant upregulation of RNA-binding protein with serine-rich domain 1(RNPS1)in HNSCC,where RNPS1 inhibits the ubiquitination degradation of NAT10 by E3 ubiquitin ligase,zinc finger SWIM domain-containing protein 6(ZSWIM6),through direct protein interaction,thereby promoting high NAT10 expression in HNSCC.This upregulated NAT10 stability mediates the enhancement of specific tRNA ac4C modifications,subsequently boosting the translation process of genes involved in pathways such as IL-6 signaling,IL-8 signaling,and PTEN signaling that play roles in regulating HNSCC malignant progression,ultimately influencing the survival and prognosis of HNSCC patients.Additionally,we pioneered the development of TRMC-seq,leading to the discovery of novel tRNA-ac4C modification sites,thereby providing a potent sequencing tool for tRNA-ac4C research.Our findings expand the repertoire of tRNA ac4C modifications and identify a role of tRNA ac4C in the regulation of mRNA translation in HNSCC.