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.

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.

Traditional development of small protein scaffolds has relied on display technologies and mutation-based engineering, which limit sequence and functional diversity, thereby constraining their therapeutic and application potential. Protein design tools have significantly advanced the creation of novel protein sequences, structures, and functions. However, further improvements in design strategies are still needed to more efficiently optimize the functional performance of protein-based drugs and enhance their druggability. Here, we extended an evolution-based design protocol to create a novel minibinder, BindHer, against the human epidermal growth factor receptor 2 (HER2). It not only exhibits super stability and binding selectivity but also demonstrates remarkable properties in tissue specificity. Radiolabeling experiments with ^99mTc, ⁶⁸Ga, and ¹⁸F revealed that BindHer efficiently targets tumors in HER2-positive breast cancer mouse models, with minimal nonspecific liver absorption, outperforming scaffolds designed through traditional engineering. These findings highlight a new rational approach to automated protein design, offering significant potential for large-scale applications in therapeutic mini-protein development.

In recent years, the rapid development of transportation and sports industries, coupled with the accelerated population aging in China, has led to a steady increase in the incidence of articular cartilage injuries, wear, and degenerative changes. Currently, the clinical treatment options for cartilage defects primarily include conservative therapies and surgical interventions, both of which have certain limitations. Cartilage tissue engineering (CTE), as a novel technology, provides an infinite prospect for cartilage regeneration and repair. Because of the abilities of scaffolds to mimic the natural cartilage structure, exhibit excellent biocompatibility and biomimetic mechanical properties, and promote cell adhesion and proliferation, scaffolds are considered effective delivery systems for growth factors, genes, and drugs. This review summarizes the clinical treatments for cartilage defects and their limitations, discusses the materials and preparation techniques of scaffolds used in CTE, with a particular focus on drug-loaded scaffold delivery systems in cartilage repair and regeneration, and offers a perspective on the future application of drug-loaded CTE. The aim is to provide theoretical guidance and new approaches for the repair of cartilage defects.
Tissue Engineering/methods* ; Humans ; Tissue Scaffolds ; Drug Delivery Systems/methods* ; Regeneration ; Cartilage, Articular/physiology* ; Animals ; Biocompatible Materials

In this study, RAW264.7 cells were employed to investigate the effects of honey-processed Astragalus on their energy metabolism and polarization, and explore the scientific connotation of the enhanced efficacy of honey-processed Astragalus on invigorating spleen-stomach and replenishing Qi. The medicated sera were prepared by intragastric administration of rats with water extracts of crude and honey-processed Astragalus, and the composition changes of medicated sera of crude and honey-processed Astragalus were analyzed by using LC-MS technology. The cell survival rates were detected and the concentrations of medicated sera were screened through CCK-8 assay. The differences of cell phagocytic rates, ATP energy metabolism, and NO secretion between crude and honey-processed Astragalus were evaluated by using neutral red phagocytosis assay, ATP detection kit, and NO detection kit. The effects of crude and honey-processed Astragalus on TNF-α secretion of RAW264.7 cells were detected by employing ELISA kit. The effects of crude and honey-processed Astragalus on polarization of RAW264.7 cells were evaluated by utilizing flow cytometry. The differential metabolites related to glycolysis in cell lysates and culture media were screened by using LC-MS technology. The experiment was approved by the experimental animal ethics committee from Shanxi University of Chinese Medicine (No. AWE202407352). The results showed that the contents of betaine, amino acids, and ononin in the prepared medicated sera of rats treated by intragastric administration with water extracts of honey-processed Astragalus increased compared to those in crude one. The results of CCK-8 experiment showed that there were no cytotoxic effects on RAW264.7 cells in the medicated sera of crude and honey-processd Astragalus at different concentration. The phagocytic index and ATP yield both increased to varying degrees after administration of the medicated sera to cells. The secretion of NO in normal and inflammatory cells increased and decreased respectively, and the effect of honey-processed Astragalus was better than that of crude one. The results of ELISA kit showed that the medicated sera of both crude and honey-processed Astragalus could promote the secretion of TNF-α in a concentration-dependent manner, and the promoting effect of honey-processed Astragalus was stronger than that of crude one. The results of flow cytometry showed that the medicated sera of both crude and honey-processed Astragalus could promote M1-type polarization and inhibit M2-type polarization of RAW264.7 cells, and the effect of honey-processed Astragalus was better than that of crude one. Compared to crude Astragalus, the metabolites related to glycolysis in the cell lysates and culture media of the medicated sera of honey-processed Astragalus were generally on the rise, indicating that the effect on promoting glycolysis of honey-processed Astragalus was better than that of crude one. In summary, honey-processed Astragalus can promote the polarization and energy metabolism of RAW264.7 cells, and participate in positive immune regulation, which is correlated with its enhanced effect of invigorating spleen-stomach and replenishing Qi.

Objective:To establish the quality standard of the standard decoction of wine-processed Coptidis Rhizoma by studying the extraction rate, fingerprint and component quantitative analysis.Methods:ccording to the Technical Requirements for Quality Control and Standard Formulation of Chinese Medicine Formula Granules, 15 batches of the standard decoction of wine-processed Coptidis Rhizoma were prepared, and the paste rate was determined; HPLC fingerprints of 15 batches of standard decoction of wine-processed Coptidis Rhizoma were established, and evaluated by combining similarity evaluation, clustering analysis, principal component analysis and orthogonal partial least squares discriminant analysis; the contents of berberine, epiberberine, pamadine, and safranine in the samples of the 15 batches were determined and analyzed their transfer rates.Results:A total of 15 batches of standard decoction samples were calibrated with 11 common peaks, referring to the recognition of 8 components. The similarity between the samples and the control product was greater than 0.900; the clustering analysis could cluster the 15 batches of samples into 2 classes; the results of the principal component analysis showed that the cumulative variance contribution rate of the 3 principal component factors was 89.388%; the OPLS-DA screened out the 3 components of the quality difference; the 15 batches of samples out of the paste rate was 15.7% -20.8%, and the mass fractions of berberine, epiberberine, safranine, and palmatine were 18.47%-24.38%, 2.82%-3.49%, 5.08%-6.69%, and 4.84%-6.68%, respectively, with transfer rates of 41.7%-61.7%, 46.9%-68.7%, 39.8%-61.5%, and 43.8%-65.2%.Conclusion:The fingerprint and content determination method established in this study is accurate, stable, simple, and can be used for the quality control and evaluation of the standard decoction of wine-processed Coptidis Rhizoma.

Eucommiae Cortex, the dried bark of Eucommia ulmoides( Eucommiaceae), has both medicinal and edible values.Modern research has shown that Eucommiae Cortex contains various components such as flavonoids, lignans, iridoids, phenolic acids,terpenoids, and steroids, which have anti-osteoporosis, antioxidant, anti-inflammatory, blood glucose-lowering, and gastrointestinal tract-protecting effects. Eucommiae Cortex has applications in multiple fields such as healthcare, industry, and animal husbandry,demonstrating broad development prospects. This article reviews the chemical constituents, pharmacological effects, and quality control status of Eucommiae Cortex. Furthermore, according to the concept of quality marker(Q-marker), this article predicts the Q-markers of Eucommiae Cortex from traditional medicinal properties, traditional medicinal effects, new medicinal effects, measurability of chemical components, compatibility, harvesting periods, and geographical origins. The components such as pinoresinol diglucoside,chlorogenic acid, caffeic acid, quercetin, baicalein, baicalin, olivil, coniferyl ferulate, and kaempferol can be used as Q-markers for Eucommiae Cortex, which provide reference for establishing a systematic quality control system for Eucommiae Cortex.
Eucommiaceae/chemistry* ; Drugs, Chinese Herbal/pharmacology* ; Quality Control ; Humans ; Animals