1.Current status and influencing factors of work readiness in patients returning to work after lung cancer surgery
Yuanyuan YIN ; Xingxia LONG ; Jie ZHANG ; Yanli, JI ; Ying ZHU ; Lijun HE ; Mei YANG
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(07):1079-1084
Objective To investigate the current status of work readiness and its influencing factors among patients returning to work after lung cancer surgery. Methods A retrospective study was conducted on young and middle-aged postoperative lung cancer patients who were treated at the Department of Thoracic Surgery, West China Hospital, Sichuan University from March to September 2023 and returned to their jobs. Data were collected through a general information questionnaire, readiness for return-to-work scale (RRTW), general self-efficacy scale (GSES), and simplified coping style questionnaire (SCSQ). Univariate and multivariate logistic regression analyses were used to explore the factors affecting the work readiness of patients returning to work. Results A total of 219 patients were included, with 59 males and 160 females aged 18-60 years. Among the postoperative lung cancer patients returning to work, 73.1% were in the active maintenance stage of return-to-work readiness with a RRTW score of (17.59±1.48) points, and 26.9% were in the uncertain maintenance stage with a RRTW score of (16.22±1.50) points. Multivariate logistic regression analysis showed that patients aged≤30 years (OR=52.381), employees of enterprises and institutions (OR=7.682), agricultural, pastoral, fishery, forestry laborers (OR=15.665), positive coping (OR=5.043), those with higher self-efficacy (OR=1.157) and engaged in physically demanding work (OR=2.449) had higher return-to-work readiness, while patients with≥2 children (OR=0.055), self-payment (OR=0.044), and those working more than 40 hours per week (OR=0.122) had lower return-to-work readiness. Conclusion The return-to-work readiness of young and middle-aged postoperative lung cancer patients needs to be improved, and occupation, job nature, main coping styles, general self-efficacy and other factors are associated with return-to-work readiness.
2.Clinical significance of cytokeratin 19 fragment in anti-melanoma differentiation-associated protein-5 antibody positive patients
Wenjuan GUAN ; Lijun LIU ; Panpan ZHANG ; Cong WANG ; Xin ZHANG ; Lijuan ZHANG ; Lishuai HAN ; Yinli ZHANG ; Yujie HE ; Shengyun LIU
Chinese Journal of Rheumatology 2025;29(3):189-196
Objective:To investigate the clinical significance of elevated cytokeratin 19 fragment (CYFRA21-1) in patients with dermatomyositis associated with positive anti-melanoma differentiation-associated gene 5 (MDA5) antibody.Methods:142 consecutive cases with newly onset anti-MDA5(+) (MADEDM)-DM admitted to the first affiliated hospital of Zhengzhou University from June 2018 to October 2021 were enrolled. They were divided into two groups, the low serum CYFRA21-1 group (CYFRA21-1≤4 ng/ml) and the high serum CYFRA21-1 group (CYFRA21-1>4 ng/ml). The clinical manifestations, laboratory tests results, imaging examinations treatment and outcome were collected for statistical analysis. Enumeration data were expressed as the number of cases and percentage (%). Normally distributed parameters were tested by t-test. Parameters with skewed distribution were tested by Mann-Whitney Wilcoxon analysis. Categorical variables were compared by the Chi-square test or Fisher′s exact test. Risk factor analysis was performed using Logistic regression. Cumulative survivals were described by Kaplan-Meier curves. Results:The age of onset in the high CYFRA21-1 group [(56±9)years vs. (50±10) years, t=-3.50, P=0.001] was higher than that in the low CYFRA21-1 group. Fever [63.3% (38/60) vs. 40.2% (33/82), χ2=7.39, P=0.007] was more common in the high CYFRA21-1 group, and arthritis [41.7% (25/60) vs. 69.5%(57/82), χ2=11.01, P=0.001] was less common. Myalgia, myasthenia, rashes, Raynaud′s phenomenon and skin ulcers had no significant difference between the two groups. The WBC count [5.2(4.1, 6.9)×10 9/L vs. 4.3(3.2, 6.2)×10 9/L, Z=-2.57, P=0.010], neutrophil count [4.0(2.9, 5.5)×10 9/L vs. 2.9(2.1, 4.5)×10 9/L, Z=-3.25, P=0.001] and neutrophil/lymphocyte ratio [5.75(3.50, 9.20) vs. 3.55(2.64, 5.41), Z=-3.77, P<0.001] in high CYFRA21-1 group were significantly higher than those in low CYFRA21-1 group. At the same time, LDH [384(302, 519)U/L vs. 318(260, 405)U/L, Z=-2.98, P=0.003], ferritin [1 204(677, 2 039)ng/ml vs. 570(229, 846)ng/ml, Z=-4.78, P<0.001], KL-6 [995(658, 1 491)U/ml vs. 750(563, 1 197)U/ml, Z=-2.49, P=0.013], ESR [36(22, 61)mm/1 h vs. 28(15, 46)mm/1 h, Z=-2.18, P=0.029] and CRP [9.2(4.7, 31.5)mg/L vs. 3.1(1.1, 11.6)mg/L, Z=-3.53, P<0.001] were significantly increased in the high level of CYFRA21-1 group, while serum albumin[(32±5)g/L vs. (35±5)g/L, t=3.92, P<0.001] was significantly decreased. There was no significant difference in the titers of serum anti-MDA5 antibodies between the two groups. The positive rate of anti-RO52 antibody [44(74.6%) vs. 44(53.7%), χ2=6.40, P=0.011] in high CYFRA21-1 group was higher than that in low CYFRA21-1 group. The ground glass opacity (GGO) score [1.75(1.33, 2.42) vs. 1.09(0.67, 1.67), Z=-4.60, P<0.001] based on high resolution CT (HRCT) was also significantly increased in the CYFRA21-1 high level group. Compared with the low CYFRA21-1 group, the high CYFRA21-1 group had a higher probability of RP-ILD [48.3%(29/60) vs. 23.2%(19/82), χ2=9.80, P=0.002] and a higher 6-month mortality rate[48.3%(29/60) vs.13.4%(11/82), χ2=19.70, P<0.001]. Logistic regression analysis showed that age ≥53 years old [ OR(95% CI)=5.197(1.781, 15.165), P=0.003], duration < 2 months [ OR(95% CI)=3.314 (1.058, 10.378), P=0.040], NE/LYMP >5 [ OR(95% CI)=3.443(1.120, 10.586), P=0.031], CRP>5 mg/L[ OR(95% CI)=6.271(1.749, 22.480), P=0.005], CA125>14 U/ml[ OR(95% CI)=7.500 (2.409, 23.345), P=0.001] and CYFRA21-1>4 ng/ml[ OR(95% CI)=3.665(1.258, 10.676), P=0.017] were independent risk factors for death within 6 months in MDA5-DM patients. Kaplan-Meier survival curve showed that the survival rate of the high CYFRA21-1 group was significantly lower than that of the low CYFRA21-1 group( P<0.001). Conclusion:Elevated CYFRA21-1 is an independent risk factor for early mortality in MDA5-DM patients and can serve as a novel serological marker for risk stratification in these patients.
3.Application of IFN-induced protein 44-like gene methylation detection by methylation sensitive-high resolution melting in the diagnosis of systemic lupus erythematosus
Qian CHEN ; Dong′e TANG ; Yue MENG ; Lijun ZHANG ; Song HE ; Zihua YANG ; Xiaoping HONG ; Yang CUI ; Tieying HOU ; Yong DAI ; Yongzhe LI
Chinese Journal of Rheumatology 2025;29(8):639-644
Objective:To evaluate the clinical efficacy of methylation sensitive-high resolution melting curve (MS-HRM) detection of IFN-induced protein 44-like (IFI44L) gene methylation in the diagnosis of systemic lupus erythematosus (SLE), as well as the relationship between IFI44L gene markers and the early onset of SLE.Methods:From February 2020 to September 2022, the MS-HRM was used to detect the methylation level of the IFI44L gene in peripheral blood mononuclear cells of 602 SLE patients and 524 other autoimmune disease patients (excluding SLE) from Beijing Peking Union Medical College Hospital, Guangdong Provincial People′s Hospital, and Shenzhen People′s Hospital, totaling 1 126 patients. Compared with the 2012 SLICC criteria, the suspected cases were followed up for 6 months until the onset and clinical diagnosis of SLE were confirmed. The measurement data of normal distribution were expressed as mean±SD, and the consistency analysis was performed using the Kappa consistency test. The clinical diagnostic efficacy indicators were calculated using the receiver operating characteristic (ROC) curve. Results:RR (95% CI) of early suspected cases was 17.06 (9.43, 30.82). The results of IFI44L gene methylation level were in good agreement with the 2012 SLICC criteria, and the sensitivity, specificity and total coincidence rate were 90.53%, 92.56% and 91.47%, respectively. The Kappa value (95% CI) was 0.829(0.796, 0.862) ( P<0.001). The diagnostic efficiency of IFI44L gene methylation level ( Kappa value 0.817) was superior to anti-nuclear antibody, anti-SM antibody and anti-dsDNA antibody ( Kappa value 0.418, 0.216 and 0.440, respectively). The Kappa values (95% CI) of methylation between MS-HRM and pyrosequencing was 0.861(0.806, 0.916), P<0.001. Conclusion:The hypomethylation of IFI44L gene methylation level detected by MS-HRM is closely related to the occurrence and development of SLE, and its diagnostic performance is better than that of three autoantibodies in SLE diagnosis, which can be used for the early diagnosis of SLE.
4.Analysis on the effect of trend analysis for safe risk in management and control for infection of medical device
Gezhi ZHEN ; Jiejie LI ; Lijun QIN ; Xingxing YANG ; Yingli HE
China Medical Equipment 2025;22(9):109-113
Objective:To analyze application effect of trend analysis for safe risk in management and control for infection of medical devices,so as to optimize the management path for medical devices.Methods:Focusing on the main factors affecting the safety risks of medical devices,the least squares method of linear regression was applied for trend analysis to optimize the device management path and strengthen management.A total of 70 clinically used medical devices in the First Affiliated Hospital of Xi'an Jiaotong University from January to December 2024 were selected.These devices were managed using two models:the conventional management model and the trend analysis management model,with 35 devices under each model.The infection risk rate of medical equipment and the equipment management quality score were compared between the two management models.Additionally,160 patients managed under the two models(80 patients per model)were included to compare the patient infection rate.Results:In the 450 diagnostic and treated records of sampling inspection and consultation for medical devices from treatment equipment,diagnosis equipment,auxiliary imaging equipment and surgical equipment,the rate of infectious risk of using management mode with trend analysis were respectively 1.78%(8/450),2.22%(10/450),2.22%(10/450)and 2.44%(11/450),all of which were significantly lower than these of using conventional management mode,and the differences were significant(x2=9.904,8.902,10.465,10.770,P<0.05).The scores of cleaning quality,the quality of disinfection and sterilization,the quality of distribution,and the retrieving quality of the management mode with trend analysis for medical devices were significantly higher than those of the conventional management mode,and the differences were statistically significant(t=15.889,13.172,15.872,17.399,P<0.05).The infection rate of patients in the trend analysis management mode was 6.25%(5/80),which was significantly lower than that in the conventional management mode[22.50(18/80)],and the difference was statistically significant(x2=11.006,P<0.05).Conclusion:The trend analysis for safe risk can analyze the risk factors in use and operation for medical devices from multiple perspectives,and mining main factors and conduct intervention for the devices,and reduce the incidence of safe risks of medical devices and the patients'infection rate,and improve the quality of clinical services.
5.Effects of step frequency-controlled walking exercise on vascular endothelial injury in postmenopausal patients with essential hypertension
He LI ; Zhenhua GAO ; Renwei WANG ; Lijun WENG ; Diqun XU
Chinese Journal of Sports Medicine 2025;44(8):626-633
Objective To explore the effect of step frequency-controlled walking exercise on vascular endothelial injury in postmenopausal patients with essential hypertension.Methods According to the screening criteria,postmenopausal women aged 55~60 years with essential hypertension and age-matched healthy women with normal blood pressure were recruited.The hypertensive patients were fur-ther divided into an exercise training group(ET)(n=23)that received step frequency-based walking intervention,and a positive control group(PC)(n=23)without exercise intervention.The normotensive healthy subjects were assigned to a negative control group(NC)(n=23).The exercise training lasted 45 to 60 minutes every other day,at least three times a week,for 12 weeks.Before and after the in-tervention,the following parameters were measured:morphological indices[body fat percentage and waist-to-hip ratio(WHR)],blood pressure indicators[systolic blood pressure(SBP)and diastolic blood pressure(SDP)],lipid metabolism markers consisting of the total cholesterol(TC),triglycerides(TG),low-density lipoprotein cholesterol(LDL-c),and high-density lipoprotein cholesterol,and vascular en-dothelial injury parameters such as endothelial microparticles(EMPs),high-sensitivity C-reactive pro-tein(hs-CRP),and superoxide dismutase(SOD).Results After the intervention,the ET group exhibit-ed significant improvements compared to baseline(P<0.05).Specifically,reductions were observed in body fat percentage,WHR,SBP,TC,TG,LDL-c,EMPs,and hs-CRP(P<0.05).Meanwhile,HDL-c and SOD levels increased significantly(P<0.05).Most of the above indicators demonstrated sig-nificant improvements in the ET group compared to the PC group after the intervention(P<0.05).Con-clusion A 12-week step frequency-controlled walking exercise at moderate intensity improves body com-position,SBP,lipid metabolism,and vascular endothelial function in postmenopausal patients with hy-pertension,suggesting its potentialto reduce cardiovascular risk in this population.
6.Targeting of stromal MAOA expression in the immune microenvironment of prostate cancer using a dual-humanized mouse model
Zhite ZHAO ; Xinglin HE ; Changhong SHI ; Lijun YANG
Acta Laboratorium Animalis Scientia Sinica 2025;33(4):479-488
Objective Construction of an immune-tumor dual humanized mouse model to explore the role of targeting monoamine oxidase A(MAOA)in the immune microenvironment of prostate cancer.Methods Bioinformatics analysis was used to examine the relationship between MAOAhigh cancer associated fibroblasts(CAFs)and T cells in prostate cancer.Multiplex immunofluorescence was employed to analyze the relationship between stromal MAOA expression and CD8+T cells.An immune-tumor dual humanized mouse model was constructed for in vivo verification of the infiltration of CD8+T cells in response to the targeting of stromal MAOA.Results MAOA expression in the stroma was inversely proportional to the infiltration of CD8+T cells.Inhibiting MAOA expression in the stroma enhanced the infiltration of CD8+T cells in vivo,which may reflect suppression of the accumulation of collagen in the tumor microenvironment.Conclusions Stromal MAOA plays an important role in the immunosuppressive microenvironment of prostate cancer,and its inhibition may promote the infiltration of immune cells.MAOA inhibitors have therapeutic potential in immune combination therapy for patients with prostate cancer.
7.Effects of ascites grading and the application of non-selective beta-blockers on the 1-year prognosis of acute-on-chronic liver failure
Wanshu LIU ; Lijun SHEN ; Xi HE ; Hua TIAN ; Qinghui ZHAI ; Dongze LI ; Shaojie XIN ; Shaoli YOU
Chinese Journal of Hepatology 2025;33(1):57-62
Objective:To investigate the effects of ascites grading and the application of non-selective beta-blockers (NSBBs) on the 1-year prognosis of acute-on-chronic liver failure (ACLF).Methods:1 386 ascitic cases with ACLF were graded and followed up for one year. The 1-year prognostic effect of ascites grade and NSBBs was analyzed on ACLF by the Kaplan Meier Log-rank test, Cox stepwise regression, and multivariate regression.The t-test, Mann-Whitney U, or Kruskal-Wallis test were used for intergroup comparison of measurement data. The χ2 test was used for intergroup comparison of numerical data. Results:The incidence rate of ascites at admission was 77.56% in 1 386 ACLF cases. The Log-rank (Mantel-Cox) of the 1-year survival curve test for 1 386 ACLF patients with ascites grade was 21.384, P<0.01. Multivariate regression and Cox stepwise regression analysis showed that ascites grade, age, gastrointestinal bleeding, pulmonary infection, acute kidney injury, prothrombin activity (PTA), urea, MELD-Na score, and the use of NSBBs were closely related to the 1-year prognosis of ACLF. The log rank (Mantel-Cox) of NSBBs treatment in the grade 2/3 ascites group was 6.113, P=0.013, and the difference was statistically significant, suggesting that NSBBs treatment can help improve the 1-year survival rate in ACLF patients with grade 2 and 3 ascites. Conclusions:Ascites grading and the use of NSBBs affect the prognostic factor of ACLF at one year. NSBBs may be beneficial for the long-term prognosis of ACLF, and treatment can be continued in patients who have already received NSBBs prior to the onset of ACLF.
8.Clinical significance of cytokeratin 19 fragment in anti-melanoma differentiation-associated protein-5 antibody positive patients
Wenjuan GUAN ; Lijun LIU ; Panpan ZHANG ; Cong WANG ; Xin ZHANG ; Lijuan ZHANG ; Lishuai HAN ; Yinli ZHANG ; Yujie HE ; Shengyun LIU
Chinese Journal of Rheumatology 2025;29(3):189-196
Objective:To investigate the clinical significance of elevated cytokeratin 19 fragment (CYFRA21-1) in patients with dermatomyositis associated with positive anti-melanoma differentiation-associated gene 5 (MDA5) antibody.Methods:142 consecutive cases with newly onset anti-MDA5(+) (MADEDM)-DM admitted to the first affiliated hospital of Zhengzhou University from June 2018 to October 2021 were enrolled. They were divided into two groups, the low serum CYFRA21-1 group (CYFRA21-1≤4 ng/ml) and the high serum CYFRA21-1 group (CYFRA21-1>4 ng/ml). The clinical manifestations, laboratory tests results, imaging examinations treatment and outcome were collected for statistical analysis. Enumeration data were expressed as the number of cases and percentage (%). Normally distributed parameters were tested by t-test. Parameters with skewed distribution were tested by Mann-Whitney Wilcoxon analysis. Categorical variables were compared by the Chi-square test or Fisher′s exact test. Risk factor analysis was performed using Logistic regression. Cumulative survivals were described by Kaplan-Meier curves. Results:The age of onset in the high CYFRA21-1 group [(56±9)years vs. (50±10) years, t=-3.50, P=0.001] was higher than that in the low CYFRA21-1 group. Fever [63.3% (38/60) vs. 40.2% (33/82), χ2=7.39, P=0.007] was more common in the high CYFRA21-1 group, and arthritis [41.7% (25/60) vs. 69.5%(57/82), χ2=11.01, P=0.001] was less common. Myalgia, myasthenia, rashes, Raynaud′s phenomenon and skin ulcers had no significant difference between the two groups. The WBC count [5.2(4.1, 6.9)×10 9/L vs. 4.3(3.2, 6.2)×10 9/L, Z=-2.57, P=0.010], neutrophil count [4.0(2.9, 5.5)×10 9/L vs. 2.9(2.1, 4.5)×10 9/L, Z=-3.25, P=0.001] and neutrophil/lymphocyte ratio [5.75(3.50, 9.20) vs. 3.55(2.64, 5.41), Z=-3.77, P<0.001] in high CYFRA21-1 group were significantly higher than those in low CYFRA21-1 group. At the same time, LDH [384(302, 519)U/L vs. 318(260, 405)U/L, Z=-2.98, P=0.003], ferritin [1 204(677, 2 039)ng/ml vs. 570(229, 846)ng/ml, Z=-4.78, P<0.001], KL-6 [995(658, 1 491)U/ml vs. 750(563, 1 197)U/ml, Z=-2.49, P=0.013], ESR [36(22, 61)mm/1 h vs. 28(15, 46)mm/1 h, Z=-2.18, P=0.029] and CRP [9.2(4.7, 31.5)mg/L vs. 3.1(1.1, 11.6)mg/L, Z=-3.53, P<0.001] were significantly increased in the high level of CYFRA21-1 group, while serum albumin[(32±5)g/L vs. (35±5)g/L, t=3.92, P<0.001] was significantly decreased. There was no significant difference in the titers of serum anti-MDA5 antibodies between the two groups. The positive rate of anti-RO52 antibody [44(74.6%) vs. 44(53.7%), χ2=6.40, P=0.011] in high CYFRA21-1 group was higher than that in low CYFRA21-1 group. The ground glass opacity (GGO) score [1.75(1.33, 2.42) vs. 1.09(0.67, 1.67), Z=-4.60, P<0.001] based on high resolution CT (HRCT) was also significantly increased in the CYFRA21-1 high level group. Compared with the low CYFRA21-1 group, the high CYFRA21-1 group had a higher probability of RP-ILD [48.3%(29/60) vs. 23.2%(19/82), χ2=9.80, P=0.002] and a higher 6-month mortality rate[48.3%(29/60) vs.13.4%(11/82), χ2=19.70, P<0.001]. Logistic regression analysis showed that age ≥53 years old [ OR(95% CI)=5.197(1.781, 15.165), P=0.003], duration < 2 months [ OR(95% CI)=3.314 (1.058, 10.378), P=0.040], NE/LYMP >5 [ OR(95% CI)=3.443(1.120, 10.586), P=0.031], CRP>5 mg/L[ OR(95% CI)=6.271(1.749, 22.480), P=0.005], CA125>14 U/ml[ OR(95% CI)=7.500 (2.409, 23.345), P=0.001] and CYFRA21-1>4 ng/ml[ OR(95% CI)=3.665(1.258, 10.676), P=0.017] were independent risk factors for death within 6 months in MDA5-DM patients. Kaplan-Meier survival curve showed that the survival rate of the high CYFRA21-1 group was significantly lower than that of the low CYFRA21-1 group( P<0.001). Conclusion:Elevated CYFRA21-1 is an independent risk factor for early mortality in MDA5-DM patients and can serve as a novel serological marker for risk stratification in these patients.
9.Application of IFN-induced protein 44-like gene methylation detection by methylation sensitive-high resolution melting in the diagnosis of systemic lupus erythematosus
Qian CHEN ; Dong′e TANG ; Yue MENG ; Lijun ZHANG ; Song HE ; Zihua YANG ; Xiaoping HONG ; Yang CUI ; Tieying HOU ; Yong DAI ; Yongzhe LI
Chinese Journal of Rheumatology 2025;29(8):639-644
Objective:To evaluate the clinical efficacy of methylation sensitive-high resolution melting curve (MS-HRM) detection of IFN-induced protein 44-like (IFI44L) gene methylation in the diagnosis of systemic lupus erythematosus (SLE), as well as the relationship between IFI44L gene markers and the early onset of SLE.Methods:From February 2020 to September 2022, the MS-HRM was used to detect the methylation level of the IFI44L gene in peripheral blood mononuclear cells of 602 SLE patients and 524 other autoimmune disease patients (excluding SLE) from Beijing Peking Union Medical College Hospital, Guangdong Provincial People′s Hospital, and Shenzhen People′s Hospital, totaling 1 126 patients. Compared with the 2012 SLICC criteria, the suspected cases were followed up for 6 months until the onset and clinical diagnosis of SLE were confirmed. The measurement data of normal distribution were expressed as mean±SD, and the consistency analysis was performed using the Kappa consistency test. The clinical diagnostic efficacy indicators were calculated using the receiver operating characteristic (ROC) curve. Results:RR (95% CI) of early suspected cases was 17.06 (9.43, 30.82). The results of IFI44L gene methylation level were in good agreement with the 2012 SLICC criteria, and the sensitivity, specificity and total coincidence rate were 90.53%, 92.56% and 91.47%, respectively. The Kappa value (95% CI) was 0.829(0.796, 0.862) ( P<0.001). The diagnostic efficiency of IFI44L gene methylation level ( Kappa value 0.817) was superior to anti-nuclear antibody, anti-SM antibody and anti-dsDNA antibody ( Kappa value 0.418, 0.216 and 0.440, respectively). The Kappa values (95% CI) of methylation between MS-HRM and pyrosequencing was 0.861(0.806, 0.916), P<0.001. Conclusion:The hypomethylation of IFI44L gene methylation level detected by MS-HRM is closely related to the occurrence and development of SLE, and its diagnostic performance is better than that of three autoantibodies in SLE diagnosis, which can be used for the early diagnosis of SLE.
10.Cryo-EM structures of Nipah virus polymerase complex reveal highly varied interactions between L and P proteins among paramyxoviruses.
Lu XUE ; Tiancai CHANG ; Jiacheng GUI ; Zimu LI ; Heyu ZHAO ; Binqian ZOU ; Junnan LU ; Mei LI ; Xin WEN ; Shenghua GAO ; Peng ZHAN ; Lijun RONG ; Liqiang FENG ; Peng GONG ; Jun HE ; Xinwen CHEN ; Xiaoli XIONG
Protein & Cell 2025;16(8):705-723
Nipah virus (NiV) and related viruses form a distinct henipavirus genus within the Paramyxoviridae family. NiV continues to spillover into the humans causing deadly outbreaks with increasing human-bat interaction. NiV encodes the large protein (L) and phosphoprotein (P) to form the viral RNA polymerase machinery. Their sequences show limited homologies to those of non-henipavirus paramyxoviruses. We report two cryo-electron microscopy (cryo-EM) structures of the Nipah virus (NiV) polymerase L-P complex, expressed and purified in either its full-length or truncated form. The structures resolve the RNA-dependent RNA polymerase (RdRp) and polyribonucleotidyl transferase (PRNTase) domains of the L protein, as well as a tetrameric P protein bundle bound to the L-RdRp domain. L-protein C-terminal regions are unresolved, indicating flexibility. Two PRNTase domain zinc-binding sites, conserved in most Mononegavirales, are confirmed essential for NiV polymerase activity. The structures further reveal anchoring of the P protein bundle and P protein X domain (XD) linkers on L, via an interaction pattern distinct among Paramyxoviridae. These interactions facilitate binding of a P protein XD linker in the nucleotide entry channel and distinct positioning of other XD linkers. We show that the disruption of the L-P interactions reduces NiV polymerase activity. The reported structures should facilitate rational antiviral-drug discovery and provide a guide for the functional study of NiV polymerase.
Nipah Virus/chemistry*
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Cryoelectron Microscopy
;
Viral Proteins/genetics*
;
RNA-Dependent RNA Polymerase/genetics*
;
Phosphoproteins/genetics*
;
Humans
;
Models, Molecular
;
Protein Binding

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