1.Mechanism of drug-containing serum of Dianxianqing granules in inhibiting microglial ferroptosis
Guangkun FAN ; Yue QI ; Jixian WANG ; Wei CHEN ; Chunpeng XIA ; Yihang WANG ; Yue ZHAO ; Yang AN
China Pharmacy 2026;37(3):317-323
OBJECTIVE To explore the potential mechanism by which drug-containing serum of Dianxianqing granules (DXQ) inhibits microglial ferroptosis. METHODS Male SD rats were given normal saline and Dianxianqing granules solution via intragastric administration to prepare normal serum and DXQ, respectively. Mice microglia BV2 cells were collected and successfully transfected with a negative control small interfering RNA (si-NC), and then they were included in the si-NC group and cultured under normal conditions. Cells successfully transfected with small interfering RNA targeting glutathione peroxidase 4 (GPX4) (si-GPX4) were divided into the si-GPX4 group, the CsA group (treated with 1 μmol/L cyclosporine A), and the DXQ- L, DXQ-M and DXQ-H groups (treated with 5%, 7% and 10% DXQ, respectively). These groups were subsequently treated with their corresponding drug solutions and ferroptosis inducer Erastin (10 μmol/L). The intracellular levels of total iron ions, glutathione (GSH), reactive oxygen species (ROS), and the expression of mitochondrial superoxide were determined in each group after 48 h of treatment. Additionally, mitochondrial membrane potential, the opening degree of mitochondrial permeability transition pore (MPTP), and mRNA expressions of GPX4 and cyclophilin D (CypD) were detected. Furthermore, the expressions of ferroptosis-related proteins[GPX4, transferrin receptor 1 (TfR1) and ferritin heavy chain 1 (FTH1)], as well as MPTP-related proteins [adenine nucleotide translocator (ANT), cytochrome C (CytC), mitochondrial calcium uniporter (MCU) and CypD] were assessed. RESULTS Compared with si-NC group, the levels of total iron ions and ROS, the expression level of mitochondrial superoxide, the opening degree of MPTP, protein and its mRNA expressions of CypD as well as protein expressions of TfR1 and MCU were increased or up-regulated significantly (P<0.01); however, GSH content, mitochondrial membrane potential, protein and mRNA expressions of GPX4, and protein expressions of FTH1, ANT and CytC were decreased or down-regulated significantly (P<0.01). Compared with the si-GPX4 group, the cells in the DXQ-M, DXQ-H groups showed a general improvement in the above quantitative indicators (P<0.01 or P<0.05). CONCLUSIONS DXQ can enhance antioxidant capacity by activating the GSH/GPX4 pathway, regulate the expressions of TfR1 and FTH1 protein to correct iron ion homeostasis, inhibit excessive opening of MPTP to improve mitochondrial function, and ultimately suppress microglial ferroptosis.
2.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.
3.Expert consensus on perioperative nursing care for myasthenia gravis patients undergoing thymectomy
Huimin DONG ; Ting ZHOU ; Yingmei ZHONG ; Wei LI ; Xiaoyan LI ; Chunfang ZHANG ; Guoyan QI ; Yangchun LIU
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(01):1-12
Myasthenia gravis is an autoimmune disorder characterized by impaired neuromuscular transmission. Thymectomy is one of the therapeutic options for acetylcholine receptor antibody-positive myasthenia gravis patients. The quality of perioperative care is directly associated with surgical safety and patient outcomes. However, there is currently a lack of specialized nursing consensus or guidelines specifically addressing the care of these patients domestically or internationally. To promote the standardization and normalization of perioperative nursing care for myasthenia gravis patients undergoing thymectomy and to ensure treatment efficacy, a panel of 57 experts from relevant fields was convened. Based on evidence-based medicine and clinical practice experience, discussions were held on various aspects including condition assessment, nutritional support, medication management, and airway care, resulting in a consensus with 18 final recommendations by using the Delphi method through two rounds of expert consultation. This consensus aims to provide a scientific reference for the perioperative nursing care of myasthenia gravis patients undergoing thymectomy.
4.Key Issues and Research Ideas of Traditional Chinese Medicine Anti-aging Guided by Essence-Qi-spirit Theory of Qiluo Doctrine
Peipei JIN ; Liping CHANG ; Cong WEI ; Mengnan LI ; Hui QI ; Hongrong LI ; Yunlong HOU ; Zhenhua JIA
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(9):240-246
Aging has emerged as a cutting edge and hotspot in global life science field, with anti-aging and geriatric disease prevention and treatment becoming critical issues urgently demanding solutions in international medical communities. In the face of the challenge of accelerating global population aging, in-depth exploration of aging mechanisms and the development of effective intervention strategies hold significant scientific and clinical value. This study supported by the national key research and development program of China, employed the essence-Qi-spirit theory of Qiluo doctrine as its guiding framework, focusing on the key scientific issue of the core traditional Chinese pathogenesis of aging, namely "depletion of kidney essence, deficiency of primordial Qi, and impairment of body and spirit". The treatment principle of "tonifying the kidney to replenish essence, harmonizing Yin and Yang, warming and invigorating primordial Qi, and nourishing the body and spirit" was established. Centered on holistic aging, systemic aging, and aging-related diseases, the research integrated multidisciplinary research approaches to construct multi-modal aging models and a multi-dimensional evaluation system, and it utilized multi-omics technologies to deeply analyze aging mechanisms. By systematically reviewing historical kidney-tonifying and anti-aging formulas and combining big data with artificial intelligence technologies, an information database of anti-aging traditional Chinese medicine substance was developed to reveal the differences and synergistic effects of various treatment methods and formulas on anti-aging. Based on this treatment method, the research integrated two millennia of kidney-tonifying medicinal experience to develop the innovative anti-aging traditional Chinese medicine, namely Bazhi Bushen capsules. It was validated that this capsule can delay holistic and systemic aging through multiple targets and mechanisms, thereby elucidating the scientific connotation of the essence-Qi-spirit theory of Qiluo doctrine in guiding anti-aging research from multiple dimensions and providing robust support for leveraging the advantages of traditional Chinese medicine to occupy the commanding heights of international anti-aging research.
5.Clinical Advantages of Traditional Chinese Medicine in Treatment of Childhood Simple Obesity: Insights from Expert Consensus
Qi ZHANG ; Yingke LIU ; Xiaoxiao ZHANG ; Guichen NI ; Heyin XIAO ; Junhong WANG ; Liqun WU ; Zhanfeng YAN ; Kundi WANG ; Jiajia CHEN ; Hong ZHENG ; Xinying GAO ; Liya WEI ; Qiang HE ; Qian ZHAO ; Huimin SU ; Zhaolan LIU ; Dafeng LONG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(6):238-245
Childhood simple obesity has become a significant public health issue in China. Modern medicine primarily relies on lifestyle interventions and often suffers from poor long-term compliance, while pharmacological options are limited and associated with potential adverse effects. Traditional Chinese Medicine (TCM) has a long history in the prevention and management of this condition, demonstrating eight distinct advantages, including systematic theoretical foundation, diversified therapeutic approaches, definite therapeutic efficacy, high safety profile, good patient compliance, comprehensive intervention strategies, emphasis on prevention, and stepwise treatment protocols. Additionally, TCM is characterized by six distinctive features: the use of natural medicinal substances, non-invasive external therapies, integration of medicinal dietetics, simple exercise regimens, precise syndrome differentiation, and diverse dosage forms. By combining internal and external treatments, TCM facilitates individualized regimen adjustment and holistic regulation, demonstrating remarkable effects in improving obesity-related metabolic indicators, regulating constitutional imbalance, and promoting healthy behaviors. However, challenges remain, such as inconsistent operational standards, insufficient high-quality clinical evidence, and a gap between basic research and clinical application. Future efforts should focus on accelerating the standardization of TCM diagnosis and treatment, conducting multicenter randomized controlled trials, and fostering interdisciplinary integration, so as to enhance the scientific validity and international recognition of TCM in the prevention and treatment of childhood obesity.
6.Clinical efficacy of robot versus video-assisted thoracoscopic surgery for the treatment of mediastinal tumor: A systematic review and meta-analysis
Wei CAO ; Haochi LI ; Kai YANG ; Qi WANG ; Zhuang ZUO ; unjiu GOU
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(05):799-806
Objective To systematically evaluate the therapeutic effects of video-assisted thoracoscopic surgery (VATS) and robot-assisted thoracic surgery (RATS) in treating mediastinal tumors. Methods A computer search was conducted on PubMed, Embase, Cochrane Library, Web of Science, Wanfang, CNKI, CBM, VIP databases for literature comparing the clinical efficacy of VATS and RATS in treating mediastinal tumors, with the search time from inception to March 31, 2024. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the included cohort studies, and Review Manager 5.4 software was used to perform a meta-analysis. Results A total of 32 articles were included, with 7868 patients. The NOS scores of the included cohort studies were all≥7 points. Meta-analysis results showed that compared with the VATS group, the RATS group had less intraoperative blood loss [MD=−16.71, 95%CI (−23.88, −9.54), P<0.001], lower conversion rate to open thoracotomy [OR=0.41, 95%CI (0.26, 0.67), P=0.003], lower overall postoperative complication rate [OR=0.66, 95%CI (0.48, 0.92), P=0.01], shorter postoperative drainage time [MD=−0.64, 95%CI (−0.92, −0.36), P<0.001], and shorter postoperative hospital stay [MD=−1.03, 95%CI (−1.28, −0.78), P<0.001]. There was no statistical difference between the two groups in terms of tumor size [MD=−0.06, 95%CI (−0.31, 0.19), P=0.64] or operation time [MD=5.52, 95%CI (−2.35, 13.40), P=0.17]. The RATS group had higher hospitalization costs than the VATS group [MD=1.69, 95%CI (1.26, 2.13), P<0.001]. Conclusion In mediastinal tumors resection, RATS is superior to VATS in terms of intraoperative blood loss, conversion rate to open thoracotomy, overall postoperative complication rate, postoperative drainage time, and postoperative hospital stay, but it increases hospitalization costs.
7.Effect of Acupuncture at Neiguan (PC6) on Improving Autism by Promoting Myelination Through The METTL14/m⁶A/PTEN Axis Based on “Xuanfu-Suiqiao” Theory
Wei-Li DANG ; Lü-Yuan LIANG ; Yu-Xin LI ; Zhi-Yao LI ; Sai-Dan LIU ; Jia-Lei CAO ; Rong-Ze MA ; Yun-Kai WANG ; Xiao-Qing YANG ; Bing-Qi WEI ; Bing-Xiang MA
Progress in Biochemistry and Biophysics 2026;53(5):1165-1177
ObjectiveTo clarify whether METTL14 mediates the core role of acupuncture at Neiguan (PC6) in promoting myelination and improving behavior in young autistic rats through gene intervention technology. MethodsThe ASD model was established by intraperitoneal injection of valproic acid (VPA) in pregnant rats. Male offspring were intracerebroventricularly injected with adenovirus-packaged METTL14 shRNA (sh-METTL14) or its control (sh-NC) on postnatal day 1, with a model group set as well. Subsequently, the juvenile rats were divided into model group, acupuncture group, acupuncture+sh-NC group, and acupuncture+sh-METTL14 group. The acupuncture group received acupuncture at Neiguan (PC6) from postnatal day 7, once daily for 21 consecutive days. Neurobehavioral changes were evaluated by behavioral tests; METTL14 knockdown efficiency and the expression of METTL14, METTL3, and PTEN were detected by quantitative real-time PCR (qRT-PCR) and Western blot (WB); PTEN m6A levels were measured by RNA immunoprecipitation-qPCR (RIP-qPCR); myelin ultrastructure, expression of myelin basic protein (MBP) and neurofascin 155 (NF155), and dendritic spine density were observed using transmission electron microscopy (TEM), enzyme-linked immunosorbent assay (ELISA), immunofluorescence, qRT-PCR, and primary neuron culture. ResultsBehaviorally, knockdown of METTL14 significantly counteracted the beneficial effects of acupuncture in improving self-grooming, open field exploration, three-chamber social interaction, and Morris water maze learning and memory (P<0.05, P<0.01). Compared with the acupuncture+sh-NC group, the acupuncture+sh-METTL14 group showed significantly decreased mRNA and protein expression of hippocampal METTL14 (P<0.01), and the upregulating effects of acupuncture on METTL3 and PTEN expression were reversed (P<0.01). Meanwhile, knockdown of METTL14 significantly inhibited the acupuncture-induced increase in PTEN m6A levels (P<0.01). Morphologically, knockdown of METTL14 attenuated the improvement of myelin structure by acupuncture, reversed the downregulation of MBP and upregulation of NF155 induced by acupuncture, and blocked the increase in dendritic spine density (P<0.05, P<0.01). ConclusionMETTL14 is a key molecule mediating the therapeutic effect of acupuncture at Neiguan. Acupuncture at Neiguan upregulates METTL14, thereby enhancing m6A methylation modification of PTEN mRNA to stabilize its expression, ultimately promoting myelin development and improving behavioral symptoms in ASD juvenile rats. This preliminarily reveals the modern biological connotation of “opening Xuanfu and dredging myelin”.
8.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.
9.Effect of Acupuncture at Neiguan (PC6) on Improving Autism by Promoting Myelination Through The METTL14/m⁶A/PTEN Axis Based on “Xuanfu-Suiqiao” Theory
Wei-Li DANG ; Lü-Yuan LIANG ; Yu-Xin LI ; Zhi-Yao LI ; Sai-Dan LIU ; Jia-Lei CAO ; Rong-Ze MA ; Yun-Kai WANG ; Xiao-Qing YANG ; Bing-Qi WEI ; Bing-Xiang MA
Progress in Biochemistry and Biophysics 2026;53(5):1165-1177
ObjectiveTo clarify whether METTL14 mediates the core role of acupuncture at Neiguan (PC6) in promoting myelination and improving behavior in young autistic rats through gene intervention technology. MethodsThe ASD model was established by intraperitoneal injection of valproic acid (VPA) in pregnant rats. Male offspring were intracerebroventricularly injected with adenovirus-packaged METTL14 shRNA (sh-METTL14) or its control (sh-NC) on postnatal day 1, with a model group set as well. Subsequently, the juvenile rats were divided into model group, acupuncture group, acupuncture+sh-NC group, and acupuncture+sh-METTL14 group. The acupuncture group received acupuncture at Neiguan (PC6) from postnatal day 7, once daily for 21 consecutive days. Neurobehavioral changes were evaluated by behavioral tests; METTL14 knockdown efficiency and the expression of METTL14, METTL3, and PTEN were detected by quantitative real-time PCR (qRT-PCR) and Western blot (WB); PTEN m6A levels were measured by RNA immunoprecipitation-qPCR (RIP-qPCR); myelin ultrastructure, expression of myelin basic protein (MBP) and neurofascin 155 (NF155), and dendritic spine density were observed using transmission electron microscopy (TEM), enzyme-linked immunosorbent assay (ELISA), immunofluorescence, qRT-PCR, and primary neuron culture. ResultsBehaviorally, knockdown of METTL14 significantly counteracted the beneficial effects of acupuncture in improving self-grooming, open field exploration, three-chamber social interaction, and Morris water maze learning and memory (P<0.05, P<0.01). Compared with the acupuncture+sh-NC group, the acupuncture+sh-METTL14 group showed significantly decreased mRNA and protein expression of hippocampal METTL14 (P<0.01), and the upregulating effects of acupuncture on METTL3 and PTEN expression were reversed (P<0.01). Meanwhile, knockdown of METTL14 significantly inhibited the acupuncture-induced increase in PTEN m6A levels (P<0.01). Morphologically, knockdown of METTL14 attenuated the improvement of myelin structure by acupuncture, reversed the downregulation of MBP and upregulation of NF155 induced by acupuncture, and blocked the increase in dendritic spine density (P<0.05, P<0.01). ConclusionMETTL14 is a key molecule mediating the therapeutic effect of acupuncture at Neiguan. Acupuncture at Neiguan upregulates METTL14, thereby enhancing m6A methylation modification of PTEN mRNA to stabilize its expression, ultimately promoting myelin development and improving behavioral symptoms in ASD juvenile rats. This preliminarily reveals the modern biological connotation of “opening Xuanfu and dredging myelin”.
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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