1.Treatment Principles and Paradigm of Diabetic Microvascular Complications Responding Specifically to Traditional Chinese Medicine
Anzhu WANG ; Xing HANG ; Lili ZHANG ; Xiaorong ZHU ; Dantao PENG ; Ying FAN ; Min ZHANG ; Wenliang LYU ; Guoliang ZHANG ; Xiai WU ; Jia MI ; Jiaxing TIAN ; Wei ZHANG ; Han WANG ; Yuan XU ; .LI PINGPING ; Zhenyu WANG ; Ying ZHANG ; Dongmei SUN ; Yi HE ; Mei MO ; Xiaoxiao ZHANG ; Linhua ZHAO
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(5):272-279
To explore the advantages of traditional Chinese medicine (TCM) and integrative TCM-Western medicine approaches in the treatment of diabetic microvascular complications (DMC), refine key pathophysiological insights and treatment principles, and promote academic innovation and strategic research planning in the prevention and treatment of DMC. The 38th session of the Expert Salon on Diseases Responding Specifically to Traditional Chinese Medicine, hosted by the China Association of Chinese Medicine, was held in Beijing, 2024. Experts in TCM, Western medicine, and interdisciplinary fields convened to conduct a systematic discussion on the pathogenesis, diagnostic and treatment challenges, and mechanism research related to DMC, ultimately forming a consensus on key directions. Four major research recommendations were proposed. The first is addressing clinical bottlenecks in the prevention and control of DMC by optimizing TCM-based evidence evaluation systems. The second is refining TCM core pathogenesis across DMC stages and establishing corresponding "disease-pattern-time" framework. The third is innovating mechanism research strategies to facilitate a shift from holistic regulation to targeted intervention in TCM. The fourth is advancing interdisciplinary collaboration to enhance the role of TCM in new drug development, research prioritization, and guideline formulation. TCM and integrative approaches offer distinct advantages in managing DMC. With a focus on the diseases responding specifically to TCM, strengthening evidence-based support and mechanism interpretation and promoting the integration of clinical care and research innovation will provide strong momentum for the modernization of TCM and the advancement of national health strategies.
2.Analysis of serological and molecular genetic characteristics of a Chinese pedigree with a B(A)06 subtype.
Dongdong TIAN ; Ding ZHAO ; Wei LI ; Zhihao LI ; Jiali YANG ; Yongfang ZHANG ; Liuchuang ZHENG
Chinese Journal of Medical Genetics 2026;43(3):220-227
OBJECTIVE:
To explore the serological and molecular genetic characteristics of a family with subtype B(A)06.
METHODS:
A neonatal hyperbilirubinemia patient who was treated at Henan Children's Hospital on June 15, 2023 due to "yellowing of the skin and gradual aggravation", and was found to have inconsistent ABO forward and reverse typing through blood type testing, was selected as the research subject. Six milliliters of peripheral blood were collected from the newborn and her family members (grandfather, grandmother, father, mother and aunt) respectively. ABO blood group identification was performed by the blood group serological method. Human genomic DNA was extracted using the nucleic acid extraction or purification reagent BT-01. ABO gene exons 2 to 7 were amplified by PCR. The PCR-specific products that were successfully amplified were sequenced by Sanger method. Taking ABO*A1.01 as the reference sequence, the ABO gene sequences of the newborn and her family members were analyzed to determine the ABO genotype. The procedures followed in this study were approved by the Ethics Committee of Henan Children's Hospital (Ethics No.: 2022-K-L036).
RESULTS:
The serological results of ABO blood group showed that the newborn, her grandfather, father and aunt were all incompatible with the forward and reverse typing. The blood group phenotype of the newborn was AwB or B(A), the blood group phenotype of the grandfather was A2B or B(A), the blood group phenotype of the father and aunt were A2B, and the blood group phenotype of the grandmother and mother were both O. The screening test results of hemolytic disease of the newborn showed that the free test detected IgG anti-A1 antibody, while the elution test, direct antiglobulin test and antibody screening results were all negative. The Sanger sequencing results showed that the newborn had variations of c.261delG, c.297A>G, c.526C>G, c.657C>T, c.703G>A, c.796C>A and c.930G>A. Her grandfather had variations of c.297A>G, C.526C>G, c.657C>T, c.703G>A, c.796C>A, c.803G>C and c.930G>A. Her grandmother had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.646T>A, c.681G>A, c.771C>T and c.829G>A. Her father and aunt had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.526C>G, c.646T>A, c.657C>T, c.681G>A, c.703G>A, c.771C>T, c.796C>A, c.829G>A and c.930G>A. Her mother had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.646T>A, c.681G>A, c.771C>T, and c.829G>A.The genotype of the newborn was ABO*BA.06/ABO*O.01.01, her grandfather was ABO*BA.06/ABO*B.01, her grandmother was ABO*O.01.02/ABO*O.01.02, her father and aunt were ABO*BA.06/ABO*O.01.02, and her mother was ABO*O.01.01/ABO*O.01.02. The ABO*BA.06 allele of the newborn, grandfather, father and aunt was caused by the c.803C>G variation in exon 7 based on the ABO*B.01 allele. The ABO*BA.06 allele can be stably inherited in this family.
CONCLUSION
The blood type of neonatal patients with B(A)06 subtype can be accurately determined by gene sequencing technology. If the forward typing is ≤ 3+ agglutination intensity in newborn ABO blood group identification, the reason should be carefully analyzed, and the molecular biology technology and family gene sequencing results should be used to jointly determine if necessary.
Humans
;
ABO Blood-Group System/genetics*
;
Female
;
Pedigree
;
Male
;
Infant, Newborn
;
Asian People/genetics*
;
Genotype
;
China
;
Blood Grouping and Crossmatching
;
Hyperbilirubinemia, Neonatal/blood*
;
East Asian People
3.Effects of ammonia poisoning on cognitive behavior and hippocampal synaptic damage in mice
Jiuxuan ZHANG ; Jinnan ZHANG ; Xiaofan SUI ; Xiaxia PEI ; Jianhong WEI ; Qiang SU ; Tian LI
Chinese Journal of Tissue Engineering Research 2026;30(5):1122-1128
BACKGROUND:Ammonia poisoning is considered to be the main hypothesis for the pathogenesis of hepatic encephalopathy.Ammonia can lead to psychiatric and cognitive behavioral disorders,although the specific pathological molecular mechanisms remain unclear.OBJECTIVE:To investigate the effects of ammonia poisoning on cognitive behavior and hippocampal neuronal synapses in mice.METHODS:Thirty-two C57BL/6J mice were randomly divided into a normal control group and an ammonium chloride group,with 16 mice in each group.Normal saline was injected intraperitoneally in the control group,and ammonium chloride(10 mmol/kg)was injected intraperitoneally in the ammonium chloride group to construct a model of ammonia poisoning,once a day.After 7 days of ammonium chloride intervention,blood samples were collected from the hearts of six mice in each group for blood ammonia concentration detection.Behavioral experiments,including the open field test,novel object recognition test,and Y-maze test,were performed to assess mental and cognitive-behavioral changes in mice.Finally,hippocampal tissues were extracted for western blot analysis to detect the expression levels of synaptophysin and postsynaptic density protein-95 in hippocampal neurons.RESULTS AND CONCLUSION:The blood ammonia concentration was significantly elevated in the ammonium chloride group compared with the control group(P<0.05).Mice in the ammonium chloride group showed anxiety-like behavior and disinhibition phenomenon,and a significant decrease in recognition memory and working memory ability.Western blot results revealed that the expression of synaptophysin and postsynaptic density protein-95 protein in hippocampal neurons in the ammonium chloride group was lower than that in the control group(P<0.05).To conclude,ammonia poisoning can induce hippocampal neuronal synaptic damage,leading to psychiatric and cognitive behavioral abnormalities in mice.
4.Improvement effects and mechanism of Achyranthes bidentata total saponins extract on vascular endothelial dysfunction in spontaneously hypertensive rats
Ruifeng LIANG ; Wenjing GE ; Xiaobo KOU ; Ping TIAN ; Hongzhi AN ; Zheng WEI ; Mingli ZHANG
China Pharmacy 2026;37(3):331-337
OBJECTIVE To investigate the improvement effects and mechanism of Achyranthes bidentata total saponins (ABS) extract on vascular endothelial dysfunction in spontaneously hypertensive rat (SHR) based on cytochrome P450 4A (CYP4A)/20-hydroxyeicosatetetraenoic acid (20-HETE)/G protein-coupled receptor 75 (GPR75) axis. METHODS Ten Wistar- Kyoto rats were taken as the normal control group. Forty SHR were first stratified by systolic blood pressure and then, within each stratum, randomly assigned using a random-number table to the model group (MOD group), captopril positive control group (CAP group, 10 mg/kg), ABS low- and high-dose extract groups (ABS-L group, ABS-H group, 60 and 120 mg/kg), with 10 rats in each group. Animals in each group were given the corresponding drug or equal volume of pure water by gavage, once a day, for 28 consecutive days. After the last administration, systolic blood pressure of rats was measured. The levels of vasoactive substances, inflammatory factors and oxidative stress indicators in serum were measured. The pathological changes of rat thoracic aorta were observed. The level of reactive oxygen species (ROS) in aortic tissue was analyzed. The expressions of endothelial nitric oxide synthase (eNOS), CYP4A, GPR75, nuclear factor-κB p65 (NF-κB p65), phosphorylated NF-κB p65, p22phox, and reduced nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4) in thoracic aorta tissue were detected. RESULTS After 28 d of treatment, compared with MOD group, the systolic blood pressure of rats in the ABS-L and ABS-H groups decreased significantly. The levels of 20-HETE, angiotensin Ⅱ, interleukin-1β, interleukin-6, tumor necrosis factor-α, intercellular cell adhesion molecule-1 and malondialdehyde in serum were significantly reduced (P<0.05 or P<0.01), while the levels of nitric oxide, superoxide dismutase, glutathione peroxidase and catalase were significantly increased (P<0.05 or P<0.01). Intimal damage of thoracic aorta was reduced, and endothelial cell morphology was improved. The expressions of ROS, CYP4A, GPR75, p22phox, NOX4 and the phosphorylation level of NF-κB p65 protein in thoracic aorta were down-regulated or reduced (P<0.05 or P<0.01), while the expression of eNOS was up-regulated (P<0.05 or P<0.01). CONCLUSIONS ABS extract may alleviate the inflammatory response and oxidative stress in SHR effectively by down-regulating the expression of CYP4A, reducing the production of 20-HETE, inhibiting the activation of GPR75, and subsequently suppressing the activation of downstream NF-κB and NOX4, thereby improving hypertension-related vascular endothelial dysfunction.
5.Investigation on the microclimate of primary and secondary school classrooms in five provinces and municipalities of China in winter
Chinese Journal of School Health 2026;47(2):158-162
Objective:
To understand the microclimate in primary and secondary school classrooms for the study period during the winter heating season, so as to provide a reference for the revision and improvement of relevant health standards.
Methods:
In December 2024, stratified random sampling was used to select 30 primary and secondary schools and 180 classrooms from the northern regions with centralized heating (Liaoning Province, Tianjin City) and the southern regions without centralized heating (Shanghai City, Anhui Province, and Jiangxi Province). Indoor temperature, relative humidity, wind speed, CO 2 and other indicators were measured on site. Variance analysis, t-test, Mann-Whitney U test and Kruskal-Wallis H test were used to analyze the differences in the microclimate of classrooms among regions and urban and rural differences.
Results:
The average temperature in the middle of the classrooms tested on site was (16.47±4.72)℃, and the variance analysis showed that the difference between the regions was statistically significant ( F=27.80, P <0.01). Among them, Tianjin had the highest average temperature of (20.43± 2.12 )℃, followed by Liaoning (19.03±2.23)℃, Shanghai (15.33±5.32)℃, Anhui (12.79±1.74)℃, and Jiangxi (11.69± 1.68 )℃. Horizontal temperature difference was 0.90 (0.50, 1.60)℃, the vertical temperature difference was 0.20 (0.10,0.60)℃, the average relative humidity was (44.39±16.16)%, the wind speed was 0.03(0.01,0.11)m/s, and the differences among different provinces and cities were statistically significant ( H/F =40.62, 82.69, 95.06, 55.28, all P <0.01). The average CO 2 volume concentration in urban areas of Tianjin, Liaoning, and Shanghai was 0.21(0.16,0.30)%, and there was no statistically significant difference ( H=4.65, P =0.10). There were grade differences in relative humidity ( F =3.71, 6.21) and CO 2 ( H =14.72, 12.92) in the north and the south (all P <0.05). In addition, the temperature, relative humidity, wind speed and CO 2 in the middle of the classroom were 42.8%, 67.8%, 100.0% and 22.2% respectively.
Conclusions
The temperature in the middle of the classroom in the non centralized heating area is lower than the standard, the relative humidity of classroom in the centralized heating area is lower than the standard,and the CO 2 in the classroom in winter is lower than the standard. It is recommended to install heating facilities in schools with low temperatures to increase the temperature and increase the frequency of ventilation in classrooms or adopt mechanical ventilation strategies to reduce CO 2 volume concentration.
6.Short-term efficacy of low-dose transscleral cyclophotocoagulation for persistent ocular hypertension in acute angle-closure glaucoma
Qiaoyun LI ; Yong JIA ; Baike ZHANG ; Xiaojing GUO ; Cong LU ; Xinli WEI ; Xuemin TIAN
International Eye Science 2026;26(4):706-710
AIM: To evaluate the safety and efficacy of low-dose transscleral cyclophotocoagulation(TSCP)in the management of persistent ocular hypertension after an acute attack of angle-closure glaucoma(AACG).METHODS:This retrospective study enrolled patients diagnosed with persistent ocular hypertension after an acute AACG attack at the No.988 Hospital of the Joint Logistics Support Force of the Chinese PLA between September 2023 and September 2024. All patients underwent low-dose TSCP using a semiconductor diode laser. Subsequent cataract surgery combined with goniosynechialysis was performed once intraocular pressure(IOP)was stabilized. Changes in anterior chamber depth(ACD), best-corrected visual acuity(VA), and IOP were compared before and after TSCP, as well as before and after phacoemulsification. Post-TSCP complications were also documented.RESULTS: A total of 21 patients(21 eyes)were enrolled, including 8 males and 13 females, with a mean age of 67.95±7.25 y. Compared with pre-cyclophotocoagulation values, ACD increased significantly at 3 d post-TSCP(1.49±0.18 vs 1.22±0.21 mm; P<0.001). BCVA and IOP decreased significantly at 1 d post-TSCP, pre-phacoemulsification, 1 wk post-phacoemulsification, and 1 mo post-phacoemulsification compared with pre-TSCP IOP(all P<0.01). Regarding postoperative complications, 2 eyes experienced pain on the day of the procedure, 5 eyes developed mild corneal endothelial folds, 2 eyes exhibited moderate anterior chamber inflammatory reaction, and 12 eyes showed shallow ciliary body detachment. No serious complications occurred during the 1-month follow-up period.CONCLUSION:Low-dose TSCP appears to be an effective bridging therapy for patients with persistent ocular hypertension following an AACG attack. It facilitates rapid IOP reduction, alleviates symptoms, and helps preserve visual function with a favorable safety profile, thereby reducing the risks associated with subsequent intraocular surgery.
7.Effects of ammonia poisoning on cognitive behavior and hippocampal synaptic damage in mice
Jiuxuan ZHANG ; Jinnan ZHANG ; Xiaofan SUI ; Xiaxia PEI ; Jianhong WEI ; Qiang SU ; Tian LI
Chinese Journal of Tissue Engineering Research 2026;30(5):1122-1128
BACKGROUND:Ammonia poisoning is considered to be the main hypothesis for the pathogenesis of hepatic encephalopathy.Ammonia can lead to psychiatric and cognitive behavioral disorders,although the specific pathological molecular mechanisms remain unclear.OBJECTIVE:To investigate the effects of ammonia poisoning on cognitive behavior and hippocampal neuronal synapses in mice.METHODS:Thirty-two C57BL/6J mice were randomly divided into a normal control group and an ammonium chloride group,with 16 mice in each group.Normal saline was injected intraperitoneally in the control group,and ammonium chloride(10 mmol/kg)was injected intraperitoneally in the ammonium chloride group to construct a model of ammonia poisoning,once a day.After 7 days of ammonium chloride intervention,blood samples were collected from the hearts of six mice in each group for blood ammonia concentration detection.Behavioral experiments,including the open field test,novel object recognition test,and Y-maze test,were performed to assess mental and cognitive-behavioral changes in mice.Finally,hippocampal tissues were extracted for western blot analysis to detect the expression levels of synaptophysin and postsynaptic density protein-95 in hippocampal neurons.RESULTS AND CONCLUSION:The blood ammonia concentration was significantly elevated in the ammonium chloride group compared with the control group(P<0.05).Mice in the ammonium chloride group showed anxiety-like behavior and disinhibition phenomenon,and a significant decrease in recognition memory and working memory ability.Western blot results revealed that the expression of synaptophysin and postsynaptic density protein-95 protein in hippocampal neurons in the ammonium chloride group was lower than that in the control group(P<0.05).To conclude,ammonia poisoning can induce hippocampal neuronal synaptic damage,leading to psychiatric and cognitive behavioral abnormalities in mice.
8.Survey of post-discharge exercise behavior and analysis of factors influencing exercise intensity in patients undergoing lung surgery
Hongyu ZENG ; Xiang WANG ; Tian ZHANG ; Yaqin WANG ; Xing WEI ; Zhen DAI ; Liping ZHANG ; Xiaoqin LIU ; Qiang LI ; Qiuling SHI ; Wei DAI ; Jia LIAO
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(05):734-742
Objective To investigate the post-discharge exercise behavior and factors influencing moderate to vigorous intensity physical activity (MVPA) in patients undergoing lung surgery. Methods A total of 2874 patients from the large prospective, observational perioperative lung symptom study cohort (CN-PRO-Lung 3) in the Department of Thoracic Surgery at Sichuan Cancer Hospital between April 7, 2021, and January 31, 2024, were selected as the survey subjects. A survey was conducted using the Investigation of Exercise Behavior after Lung Surgery questionnaire and the International Physical Activity Questionnaire-Short Form (IPAQ-SF) among patients who underwent lung surgery. Binary logistic regression was used to analyze the factors influencing patients’ engagement in MVPA. Results A total of 702 patients were surveyed, including 252 males and 450 females, with an average age of (52.4±10.2) years. Patients with lung cancer accounted for 85.9%. Only 36.0% of the patients had regular exercise habits, while 42.3% did not engage in any physical activity. The three main barriers for postoperative exercise were physical discomfort (pain, coughing, shortness of breath, etc, 54.7%), lack of professional guidance (41.7%), and concerns about the surgical wound (28.9%). The proportions of patients engaging in vigorous, moderate, and low-intensity physical activity were 5.7%, 28.2%, and 66.1%, respectively. Multivariate analysis showed that patients with a personal annual income ≥50000 yuan (OR=1.52, 95%CI 1.01-2.29, P=0.044), high school education or above (OR=1.92, 95%CI 1.33-2.76, P<0.001), and lobectomy (OR=1.44, 95%CI 1.02-2.03, P=0.037) engaged in more MVPA. Conclusion Patients undergoing lung surgery have inadequate physical activity after discharge, particularly lacking in MVPA. Patients with higher income, higher educational levels, and lobectomy are more frequently engaged in MVPA. Measures such as symptom control, providing exercise guidance, and enhancing education on wound care may potentially improve the inadequate physical activity in lung surgery patients after discharge.
9.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.
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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