1.Spatiotemporal distribution characteristics of and trends in disease burden of dengue fever in China from 2005 to 2024
Lianfang FENG ; Meng SHANG ; Jiarong REN ; Xiaoxu WANG ; Haoqiang JI ; Xinning HAO ; Jing LI ; Qiyong LIU
Chinese Journal of Schistosomiasis Control 2026;38(2):137-147
Objective To analyze the spatiotemporal distribution characteristics of and trends in the disease burden of dengue fever in China from 2005 to 2024, so as to provide insights into formulation of dengue fever control strategies. Methods Data pertaining to dengue fever cases in China from 2005 to 2024 were retrieved from the Infectious Disease Reporting Information System of Chinese Center for Disease Control and Prevention, and city population, gross domestic product (GDP), GDP per capita, and consumer price index in China were captured from the China Statistical Yearbook, National Bureau of Statistics of China, the China City Statistical Yearbook, and bureaus of statistics in each city. The disability-adjusted life years (DALYs), years of life lost (YLLs), and years lived with disability (YLDs) due to dengue fever were calculated in China from 2005 to 2024. The direct and indirect economic burdens of dengue fever were estimated to calculate the total economic burden. The trends in the disease burden of dengue fever were estimated in China from 2005 to 2024 using a Joinpoint regression model with the software Joinpoint 4.9.0.0, and the average annual percent change (AAPC) and its 95% confidence interval (CI) were calculated. In addition, the DALYs rate and economic burden of dengue fever in China were subjected to global and local spatial autocorrelation analyses using the software ArcGIS 10.8. Results The gross DALYs due to dengue fever were 5 558 person-years in China from 2005 to 2024, and the DALYs of dengue fever increased from 36 person-years in 2005 to 899 person-years in 2024, with an increase of 23.97 folds. The average annual DALYs rate of dengue fever was 0.02 person-years/105 in China during the 20-year study period from 2005 to 2024, and the DALYs rate peaked in 2014 (0.13 person-years/105) and reduced during the COVID-19 pandemic from 2020 to 2022. YLDs were the main contributor of DALYs due to dengue fever in China from 2005 to 2024, with a total of 5 354 person-years, accounting for 96.33% (5 354 person-years/5 558 person-years) of the gross DALYs. The gross DALYs of dengue fever were 2 982 person-years among men (53.66%) and 2 575 person-years among women (46.34%) in China from 2005 to 2024, and high DALYs of dengue fever were measured among residents at ages of 15 to 30 years (1 639 person-years), 30 to 45 years (1 857 person-years), and 45 to 60 years (1 204 person-years), respectively, accounting for 84.56% (4 700 person-years/5 558 person-years) of total DALYs due to dengue fever in China. The total economic burden of dengue fever was estimated to be 612 million Yuan in China from 2005 to 2024, with an average annual economic burden of 30.584 million Yuan. The economic burden of dengue fever increased from 196 000 Yuan in 2005 to 121 million Yuan in 2024 in China, with an increase of 616.35 folds, and the per capita economic burden increased from 3 322.21 Yuan in 2005 to 4 940.01 Yuan in 2024, with an increase of 48.70%. Dengue fever cases were reported in 274 cities (counties) across 31 provinces (autonomous regions, municipalities) in China from 2005 to 2024, with relatively higher DALYs in Guangdong Province and Yunnan Province. Spatial autocorrelation analysis revealed that the disease burden of dengue fever appeared positive aggregation in Chinese cities (counties) from 2005 to 2024 (global Moran’s I = 0.045, Z = 2.24, P < 0.05), with high-high clusters mainly concentrated in the Pearl River Delta region in Guangdong Province and Xishuangbanna Dai Autonomous Prefecture and Pu’er City in Yunnan Province, and the total economic burden (global Moran’s I = 0.032, Z = 9.55, P < 0.001), per capita economic burden (global Moran’s I = 0.208, Z = 27.34, P < 0.001), and the proportion of total economic burdens in GDP in 2024 (global Moran’s I = 0.017, Z = 5.91, P < 0.001) all presented positive aggregation, with relatively higher total economic burdens mainly concentrated in Guangdong Province and Yunnan Province. Joinpoint regression analysis showed that the gross DALYs rates of dengue fever appeared an overall tendency towards a rise in China from 2005 to 2024 (AAPC = 16.24%, P = 0.029), and the DALYs rate presented an overall tendency towards a rise among both men (AAPC = 14.75%, P = 0.028) and women (AAPC = 14.93%, P = 0.037) during the study period. The per capita direct economic burden appeared an overall tendency towards a rise among dengue fever patients in China from 2005 to 2024 (AAPC = 2.16%, P = 0.012); however, there was no significant difference in the trends in the per capita indirect economic burden (AAPC = 0.46%, P = 0.470). In addition, the DALYs rate of dengue fever appeared a tendency towards a rise in 84.67% (232/274) of cities (counties) in China from 2005 to 2024, and the per capita economic burden appeared a tendency towards a rise in 85.40% (234/274) of cities (counties), while the DALYs rate and per capita economic burden of dengue fever appeared a tendency towards a rise in 77.01% (211/274) of cities (counties). Conclusions The disease burden of dengue fever significantly increased in China from 2005 to 2024. It is recommended to reinforce integrated dengue fever control in high-risk areas and among high-risk populations, and to improve the surveillance of imported dengue fever cases and vector control.
2.Surveillance of Oncomelania hupensis snails following interruption of schistosomiasis transmission in Yunnan Province
Siqi NING ; Yi DONG ; Chunhong DU ; Lifang WANG ; Yun ZHANG ; Yuhe HE ; Hua JIANG ; Jiayu SUN ; Chunqiong CHEN ; Jiaqi YAN ; Jihua ZHOU ; Zongya ZHANG ; Hongqiong WANG ; Meifen SHEN ; Jing SONG
Chinese Journal of Schistosomiasis Control 2026;38(2):200-206
Objective To investigate the distribution characteristics of Oncomelania hupensis snails in Yunnan Province fol-lowing interruption of schistosomiasis transmission, so as to provide the evidence for assessing the risk of schistosomiasis transmission and scientifically formulating the schistosomiasis surveillance program. Methods According to the requirements of the National Schistosomiasis Surveillance Scheme (2020 Edition), O. hupensis snail surveillance data were collected from 18 schistosomiasis-endemic counties (cities, districts) in Yunnan Province from 2020 to 2024, including area of snail survey, area of snail habitats, area of re-emerging snail habitats, number of frames surveyed, number of frames with O. hupensis snails, number of O. hupensis snails captured, and number of living snails, and the occurrence of frames with snails and mean density of living snails were calculated. Changes in snail status over the 5-year period from 2020 to 2024 and the differences in snail distributions specified by epidemic intensity, environmental type, and vegetation type were analyzed. Results The areas of snail survey increased from 1 727.96 hm2 in 2020 to 3 894.45 hm2 in 2024 (peak) across 18 schistosomiasis-endemic counties (cities, districts) in Yunnan Province during the period from 2020 through 2024. The areas of snail habitats increased from 70.36 hm2 in 2020 to a peak in 2023 (172.04 hm2), followed by a reduction to 132.36 hm2 in 2024, and the areas of re-emerging snail habitats increased from 42.71 hm2 in 2020 to a peak in 2022 (78.43 hm2), followed by a reduction to 40.21 hm2 in 2024. The occurrence of frames with snails and mean density of living snails increased from 1.24% (3 025/244 404) and (0.033 2 ± 0.038 7) snails/0.1 m2 in 2020 to peaks at 2.03% (6 231/307 563) and (0.066 9 ± 0.068 4) snails/0.1 m2 in 2023, followed by reductions to 1.04% (5 829/559 941) and (0.032 6 ± 0.057 7) snails/0.1 m2 in 2024, respectively. There was a significant difference in the occurrence of frames with snails over the 5-year study period (χ2 = 1 962.95, P < 0.05), and the occurrence of frames with snails reduced by 48.71% in 2024 relative to in 2023 (χ2 = 1 411.05, P < 0.005); however, there was no significant difference in the mean density of living snails over the 5 years (H = 5.310, P > 0.05). There were significant differences in the occurrence of frames with snails (χ2 = 481.27, P < 0.05) and mean density of living snails (H = 6.872, P < 0.05) in schistosomiasis-endemic areas with different epidemic intensities. The occurrence of frames with snails (χ2 = 25.32 and 38.70, both P values < 0.017) and mean density of living snails (Z = 28.55 and 49.96, both P values < 0.017) were higher in schistosomiasis transmission-interrupted and eliminated areas with snails than in schistosomiasis-eliminated areas without snails, and the occurrence of frames with snails (χ2 = 453.54, P < 0.017) and mean density of living snails (Z = −56.97, P < 0.017) were higher in schistosomiasis-eliminated areas with snails than in schistosomiasis transmission-interrupted areas with snails. O. hupensis snails were mainly distributed in paddy fields, dry farmlands and ditches; however, the occurrence of frames with snails (13.40%, 424/3 164) and mean density of living snails [(0.252 8 ± 0.158 7) snails/0.1 m2] were higher in ponds/weirs than in other types of environments (both P values < 0.05). Rice, dry farmland crops and weeds were main vegetations in which O. hupensis snails were distributed, and the occurrence of frames with snails (2.29%, 7 111/310 140) and mean density of living snails [(0.072 3 ± 0.018 9) snails/0.1 m2] were higher in weeds than in other types of environments (both P values < 0.05). Conclusions O. hupensis snails have been effectively controlled in Yunnan Province following implementation of integrated schistosomiasis control measures; however, there are still risk factors for schistosomiasis transmission, including reduced attention to schistosomiasis control and snail re-emergence. Improved control efforts and surveillance system construction and timely identification of risk factors of snail status and timely management are recommended to ensure the achievement of the target of schistosomiasis elimination as scheduled.
3.Artificial Intelligence Drives Lung Cancer Diagnosis and Treatment: Research Progress and Future Prospects
Jing BAI ; Kezhong CHEN ; Jun WANG
Medical Journal of Peking Union Medical College Hospital 2026;17(3):597-606
Lung cancer, the malignancy with the highest global mortality rate, is currently undergoing a paradigm shift from precision medicine to intelligent medicine in its diagnostic and therapeutic models. Artificial intelligence (AI), leveraging its core advantages in multimodal data fusion and high-dimensional featureextraction, has deeply permeated the entire disease continuum of lung cancer screening, diagnosis, and individualized treatment. AI demonstrates significant value in improving patient outcomes and enhancing clinical efficiency, thereby reshaping the fundamental logic and clinical practice pathways of lung cancer management. This article reviews the latest advances of AI in real-world clinical diagnosis and treatment scenarios for lung cancer, with a focus on multimodal data fusion architectures, breakthrough applications of AI-assisted lung cancer diagnosis and treatment, and the practical barriers to clinical translation. It critically analyzes core challenges including data standardization, privacy protection, and ethical compliance. Finally, it envisions the future landscape of a nationwide intelligent ecosystem for lung cancer diagnosis and treatment—driven by federated learning and empowered by data elements—providing a reference for the standardized application and innovative development of AI in precision lung cancer care.
4.Interpretation of the Multidisciplinary Expert Consensus on Diagnosi and Treatment of Multiple Lung Cancers by the Chinese Anti-Cancer Association
Jianqi MAO ; Xiaoqiu YUAN ; Jing WANG ; Zhuowei LI ; Yukun CHEN ; Kezhong CHEN
Medical Journal of Peking Union Medical College Hospital 2026;17(3):626-636
With the widespread application of low-dose computed tomography (CT), the detection rate of multiple lung cancers (MLCs) is gradually increasing. The diagnosis and treatment of MLCs have become a major challenge in clinical practice in thoracic surgery and oncology. In April 2025, the Lung Cancer Professional Committee of the China Anti-Cancer Association (CACA) organized multidisciplinary experts from both domestic and international fields to release the first edition of the CACA Expert Consensus on the Diagnosis and Treatment of Multiple Lung Cancers, providing systematic recommendations for the diagnostic system, molecularassessment strategies, and surgical and non-surgical management of MLCs. This article provides a detailed interpretation of the core content of this consensus and, by incorporating the latest research progress in the field, delves into the pathogenesis, precise diagnostic strategies, and individualized treatment pathways for multiple lung cancers, aiming to offer a more comprehensive reference for clinical practice.
5.Consideration of Health Economics Evidence in Clinical Practice Guidelines: Methods and Steps
Dongrui PENG ; Qi ZHOU ; Xufei LUO ; Zijun WANG ; Hui LIU ; Junxian ZHAO ; Jinghong HUANG ; Hongyu HU ; Xin XING ; Jing WU ; Shitong XIE ; Xiaohui WANG ; Yaolong CHEN
Medical Journal of Peking Union Medical College Hospital 2026;17(3):862-870
Health economics evidence plays an important role in linking clinical value evidence with health resource allocation decisions in the development of clinical practice guidelines. It can not only effectively balance clinical effectiveness and economic feasibility but also avoid forming "idealized" recommendations that are detached from the affordability of the healthcare system or the burden-bearing capacity of patients. To promote guideline developers to use health economics evidence more standardizedly and fully, this paper conducts an in-depth analysis of the current application status, existing challenges, access channels, and application processes of health economics evidence in current guidelines, and on this basis, puts forward considerations and suggestions for strengthening and standardizing the application of health economics evidence in China's clinical practice guidelines.
6.DIA Proteomic Profiling on Staged Regulatory Effect of Tonifying Deficiency and Dredging Collaterals Method on Liver Fibrosis in Rats Based on Theory of "Zhu Ke Jiao"
Xin WANG ; Pengyu ZHU ; Li WEN ; Jibin LIU ; Aochun YUE ; Ziyi CHEN ; Jing ZHANG ; Li ZHU ; Quansheng FENG ; Cen JIANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(14):119-132
ObjectiveThis paper aims to investigate the differential mechanisms underlying the staged therapeutic effects of Qijia Rougan formula on liver fibrosis using proteomic technology. MethodsThe staged rat model of liver fibrosis was established by subcutaneous injection of carbon tetrachloride (CCl4) and olive oil. One hundred and four SD rats were randomized into thirteen groups:a normal group,a two-week model group,a four-week model group,a six-week model group,an eight-week model group,a two-week Qijia Rougan formula group,a four-week Qijia Rougan formula group,a six-week Qijia Rougan formula group,an eight-week Qijia Rougan formula group,a two-week compound Biejia Ruangan tablet group,a four-week Compound Biejia Ruangan Tablet group,a six-week Compound Biejia Ruangan Tablet group,and an eight-week compound Biejia Ruangan tablet group. After two weeks of drug intervention,liver tissue and abdominal aortic blood samples were collected from the rats for testing. Hematoxylin-eosin (HE) staining,Masson staining,and Picro Sirius red staining were used to observe pathological damage and collagen fiber deposition in liver tissues. Immunohistochemistry (IHC) was employed to detect the contents of fibrosis markers in liver tissues. The contents of liver function indicators in the serum were measured using a fully automated biochemical analyzer,and the levels of liver fibrosis indicators in the serum were assessed by enzyme-linked immunosorbent assay (ELISA). Liver tissues from the normal group,each model group,and each Qijia Rougan formula group were subjected to label-free quantitative proteomic analysis to identify differential proteins among the groups,with key proteins validated by Western blot. Finally,bioinformatics analysis was performed on the differential proteins. Results(1) The staged rat model of liver fibrosis constructed with CCl4 and olive oil showed pathological results at the 2nd,4th,6th,and 8th weeks of modeling that were consistent with the Metavir standards for the F1,F2,F3,and F4 stages. Compared with those in the normal control group,the protein expressions of α-smooth muscle actin (α-SMA) and Collagen Ⅰ were significantly increased in each stage (P<0.05). The levels of liver function indicators in the serum,including alanine aminotransferase (ALT),aspartate aminotransferase (AST),alkaline phosphatase (ALP),direct bilirubin (DBIL),and total bilirubin (TBil) in each model group,were significantly elevated in each stage (P<0.01). The levels of liver fibrosis indicators in the serum,including procollagen Ⅲ peptide (PⅢP),type Ⅳ collagen(Ⅳ-C),hyaluronic acid (HA),and laminin (LN) in each model group,were significantly increased in each stage (P<0.05,P<0.01). This study successfully established a staged rat model of liver fibrosis. (2) Compared with the model groups at each stage,the administration groups showed a reduction in hepatocyte ballooning degeneration,a more orderly arrangement of hepatocytes,and a decrease of inflammatory cell infiltration. The blue-stained collagen fibers became significantly thinner and finer,with reduced and narrowed fibrous septa. The areas of collagen fibers and Picro Sirius red staining were reduced (P<0.05). The positive areas of α-SMA and Collagen Ⅰ expression were significantly decreased (P<0.05). The levels of ALT,AST,ALP,DBIL,and TBil in the rats of the model groups at each stage were significantly reduced (P<0.05,P<0.01). The levels of PⅢP,Ⅳ-C,HA,and LN in the rats of the model groups at each stage were significantly decreased (P<0.05). Among these,the improvements in all indicators were most significant in the F3 stage (P<0.01).(3) The proteomic results show that a total of 165 differential proteins exhibit a callback trend when comparing the model groups at four stages with the normal group,and when comparing the Qijia Rougan formula group with the model group. Western blot analysis reveals that the levels of NAD(P)H:quinone oxidoreductase 1 (NQO1),mitogen-activated protein kinase 1 (MAPK1),arginase 1 (Arg1),and glutathione S-transferase α1 (GSTA1) were consistent with the proteomic results. Bioinformatics results reveal that 165 differentially expressed proteins are enriched in multiple signaling pathways. Notably,signaling pathways such as drug metabolism-cytochrome P450,arginine biosynthesis,and the peroxisome proliferator-activated receptor (PPAR) signaling pathway were found to be closely associated with liver fibrosis,suggesting that the Qijia Rougan formula may exert its staged regulatory effects on liver fibrosis by regulating these pathways. ConclusionThe Qijia Rougan formula may achieve staged regulation of liver fibrosis by regulating drug metabolism-cytochrome P450,arginine biosynthesis,and the PPAR signaling pathway.
7.Research on quality control of the potential allergic ingredient scutellarin in Shuganning Injection
HE Feng ; CAO Lu ; YANG Cuiping ; LI Jing ; ZHANG Quan ; WANG Jinjin ; L& ; #252 Yanni ; HAN Shengli
Drug Standards of China 2026;27(1):0037-0042
Objective: Scutellarin in Shuganning injection has potential allergenicity and is prone to causing anaphylactoid reactions. There is an urgent need to establish a simple and rapid chromatographic quantitative method to achieve the limit control of scutellarin in Shuganning injection.
Methods: For scutellarin, HPLC method was used in the quantitative analysis using a Shim-pack GIS C18 (2.1 mm×150 mm, 5 μm) column. The mobile phase was a blend of 0.1% trifluoroacetic acid in water and acetonitrile, and gradient elution progress was applied for the whole process. The flow rate was 0.3 mL·min-1 and the column temperature was maintained at 37 ℃. The detecting wavelength was 320 nm.
Results: The linear regression equation was y=51 456x-27 352, the correlation coefficient r=0.999 8, namely the calibration curve was linear in the range of 1.02-102.00 μg·mL-1; the average recovery was 103.76%; the detection and quantification limit for determining scutellarin was 0.16 μg·mL-1 and 0.57 μg·mL-1, respectively; the injection sample was stable at room temperature for 48 h.
Conclusion: This method is easy to operate, reproducible and has high accuracy, thus can be used for quality control of Shuganning injection.
8.Discussion on processing time for Polygonatum kingianum based on analysis of correlation between sugar components and color changes
GUO Hong ; YAO Rui ; LI Zhe ; FAN Jing ; WANG Ying ; GUO Xiaohan ; CHEN Jia ; DUAN Baozhong ; YANG Jianbo ; JING Wenguang ; CHENG Xianlong ; WEI Feng
Drug Standards of China 2026;27(1):0083-0091
Objective: To investigate the correlation between color parameters (L*, a*, b*, Eab*) and the contents of reducing sugars, total polysaccharides, total oligosaccharides, as well as four saccharides (fructose, glucose, sucrose, and kestose) during the nine cycles of steaming and sun-drying processing of Polygonatum kingianum, and to preliminarily explore the optimal processing duration.
Methods: The color changes were objectively evaluated using a colorimeter. The anthrone-sulfuric acid method was employed to determine total polysaccharides and oligosaccharides. The 3,5-dinitrosalicylic acid (DNS) colorimetric method was used to measure total reducing sugar content. High-performance liquid chromatography coupled with charged aerosol detection (HPLC-CAD) was applied for quantitative analysis of fructose, glucose, sucrose, and kestose. Multivariate statistical analysis was conducted to assess samples from different processing stages.
Results: Significant variations in color and component contents were observed across processing stages. The herbal pieces progressively darkened with increased processing cycles: brightness (L*) and total color difference (Eab*) initially decreased then stabilized, while a* (red-green) and b* (yellow-blue) values first increased then declined. Total polysaccharides and oligosaccharides showed overall decreasing trends, whereas reducing sugars initially increased before stabilizing. Fructose and glucose levels rose continuously, while sucrose and kestose decreased progressively, becoming undetectable after five cycles.
Conclusion: The chromatic alteration and saccharide composition of P. kingianum showed significant correlation with processing duration. Both total color difference (Eab*) and reducing sugar content stabilized after four processing cycles (12 hours), suggesting that four cycles of steaming and sun-drying may represent the optimal processing duration.
9.Trends and influencing factors in China's life expectancy from a Global Perspective
Jiayan GAO ; Yueyun ZENG ; Jing WANG ; Chuanhua YU
Journal of Public Health and Preventive Medicine 2026;37(3):1-7
Objective To systematically analyze the trends in life expectancy and healthy life expectancy in China from 1990 to 2023, identify the factors influencing changes in life expectancy, and provide scientific evidence for the Healthy China Strategy. Methods Based on the most recent authoritative data from the Global Burden of Disease Study 2023 (GBD 2023), the United Nations Population Division, the World Bank, and Our World in Data, complete life tables and cause-deleted life tables were constructed. Analytical methods including Joinpoint regression and ARIMA forecasting were comprehensively applied to systematically evaluate life expectancy, survival probability, and the burden of diseases and risk factors. Results From 1990 to 2023, life expectancy at birth in China exhibited sustained and rapid growth (average annual percentage change, AAPC = 0.63%), with a growth rate significantly higher than those observed in the United States, Japan, and the global average (AAPC = 0.12%, 0.21%, and 0.45%, respectively). Survival probability improved across all age groups, with particularly notable gains in children and the oldest-old. Interprovincial and sex-based disparities persisted. Cause-deleted analysis revealed that cardiovascular disease (CVD) accounted for the greatest loss in life expectancy at birth. From 2004 to 2020, years of life lost due to CVD increased annually, reaching 8.70 years in 2020 for the zero-age group in China. Neoplasm ranked second in causing life expectancy loss, which remained relatively stable at approximately 3 years over the study period. Among risk factors, tobacco use, hypertension, air pollution, dietary risks, and high fasting plasma glucose were identified as prominent contributors to life expectancy loss. Strong positive correlations were observed between health resources, economic growth, and life expectancy. Conclusion China has made remarkable progress in extending lifespan and improving quality of life, but it still faces challenges such as chronic diseases limiting lifespan and life quality, diverse health risks, and disparities in health levels and life expectancy across regions and populations.
10.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.


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