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1.
J Phys Chem A ; 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39023240

ABSTRACT

In this work, a quantitative structure-antioxidant activity relationship of flavonoids was performed using a machine learning (ML) method. To achieve lipid-soluble, highly antioxidant flavonoids, 398 molecular structures with various substitute groups were designed based on the flavonoid skeleton. The hydrogen dissociation energies (ΔG1, ΔG2, and ΔG3) related to multiple hydrogen atom transfer processes and the solubility parameter (δ) of flavonoids were calculated using molecular simulation. The group decomposition results and the calculated antioxidant parameters constituted the ML data set. The artificial neural network and random forest models were constructed to predict and analyze the contribution of the substitute groups and positions to the antioxidant activity. The results showed the hydroxyl group at positions B4', B5', and B6' and the branched alkyl group at position C3 in the flavonoid skeleton were the optimal choice for improving antioxidant activity and compatibility with apolar organic materials. Compared to the pyrogallol group-grafted flavonoid, the designed potent flavonoid decreased ΔG1 and δ by 2.2 and 15.1%, respectively, while ΔG2 and ΔG3 kept the favorable lower values. These findings suggest that an efficient flavonoid prefers multiple ortho-phenolic hydroxyl groups and suitable sites with hydrophobic groups. The combination of molecular simulation and the ML method may offer a new research approach for the molecular design of novel antioxidants.

2.
PLoS One ; 19(7): e0304809, 2024.
Article in English | MEDLINE | ID: mdl-38995923

ABSTRACT

Supporting cells(SCs) have been demonstrated to be a reliable source for regenerating hair cells(HCs). Previous research has reported that Lgr5+ SCs can regenerate HCs both in vitro and in vivo. However, there is limited knowledge about the impact of the material on Lgr5+ cells. In this study, Lgr5+ cells were isolated from neonatal Lgr5-EGFP-CreERT2 transgenic mice by flow cytometry and then plated on self-assembled silica beads (SB). Lgr5+ cell differentiation was observed by immunofluorescence. We found that in the direct differentiation assay, the SB group generated more hair cells than the control group(*p < 0.05). Especially in the SB group, Lgr5+ progenitors generated significantly more Myo7a+ HCs outside of the colony than in the control group(**p < 0.01). In the sphere differentiation assay, we found that the diameter of spheres in the SB group was significantly larger compared to those of the control group(**p < 0.01). However, the difference in the ratio of myo7a+ cell counts was not obvious(P>0.05). The experiment proved that the self-assembled silica beads could promote the differentiation of Lgr5+ progenitors in vitro. Our findings implicate that nanostructures of self-assembled silica beads can be used as vectors for stem cell research in the inner ear.


Subject(s)
Cell Differentiation , Mice, Transgenic , Nanostructures , Receptors, G-Protein-Coupled , Silicon Dioxide , Stem Cells , Animals , Silicon Dioxide/chemistry , Receptors, G-Protein-Coupled/metabolism , Stem Cells/cytology , Stem Cells/metabolism , Mice , Nanostructures/chemistry , Cells, Cultured
3.
Int J Biol Macromol ; : 133652, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38971273

ABSTRACT

Eighteen S rRNA factor 1 (ESF1) is a predominantly nucleolar protein essential for embryogenesis. Our previous studies have suggested that Esf1 is a negative regulator of the tumor suppressor protein p53. However, it remains unclear whether ESF1 contributes to tumorigenesis. In this current research, we find that increased ESF1 expression correlates with poor survival in multiple tumors including pancreatic cancer. ESF1 is able to regulate cell proliferation, migration, DNA damage-induced apoptosis, and tumorigenesis. Mechanistically, ESF1 physically interacts with MDM2 and is essential for maintaining the stability of MDM2 protein by inhibiting its ubiquitination. Additionally, ESF1 also prevented stress-induced stabilization of p53 in multiple cancer cells. Hence, our findings suggest that ESF1 is a potent regulator of the MDM2-p53 pathway and promotes tumor progression.

5.
Adv Sci (Weinh) ; : e2404433, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39005186

ABSTRACT

Growing demand for wound care resulting from the increasing chronic diseases and trauma brings intense pressure to global medical health service system. Artificial skin provides mechanical and microenvironmental support for wound, which is crucial in wound healing and tissue regeneration. However, challenges still remain in the clinical application of artificial skin since the lack of the synergy effect of necessary performance. In this study, a multi-functional artificial skin is fabricated through microfluidic spinning technology by using core-shell gel nanofiber scaffolds (NFSs). This strategy can precisely manipulate the microstructure of artificial skin under microscale. The as-prepared artificial skin demonstrates superior characteristics including surface wettability, breathability, high mechanical strength, strain sensitivity, biocompatibility and biodegradability. Notably, this artificial skin has the capability to deliver medications in a controlled and sustained manner, thereby accelerating the wound healing process. This innovative approach paves the way for the development of a new generation of artificial skin and introduces a novel concept for the structural design of the unique core-shell gel NFSs.

6.
Front Psychol ; 15: 1372694, 2024.
Article in English | MEDLINE | ID: mdl-38882513

ABSTRACT

Background: The interplay between teaching engagement and performance has garnered attention in both theoretical and empirical research, primarily due to its influence on student academic achievement, teacher well-being, and the realization of institutional goals. This is especially pertinent in the realm of preschool education, where the scope of learning extends beyond academic content to encompass the broader socialization of children. Drawing from Affective Neuroscience research, this study investigates the role of affective tendencies as mediators in the relationship between work engagement and job performance. Objective: The primary aim of this research is to examine a chain mediation model that hypothesizes the predictive role of teacher engagement. This model posits the intermediary influence of four basic emotions-CARING, SEEKING, ANGER, and FEAR-followed by the mediating effect of job satisfaction on teacher job performance. Method: The study utilized a sample of 842 Chinese preschool teachers. Data were collected through an online questionnaire, employing a time-lagged design. The analysis was conducted using Model 80 of the PROCESS Macros. Results: The findings reveal that both positive and negative emotions significantly predict teachers' job satisfaction. However, job satisfaction does not influence job performance. The analysis confirmed the direct and total effects of teacher engagement, as well as the indirect effects, particularly through the positive emotion of Caring. Implications: The results are instrumental in informing and refining interventions designed to enhance teacher engagement and performance, underscoring the importance of emotional factors in the educational environment.

8.
Oncogene ; 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38890429

ABSTRACT

The role of tumor-resident microbiota in modulating tumor immunity remains unclear. Here, we discovered an abundance of intra-tumoral bacteria, such us E.coli, residing and resulting in Colorectal cancer liver metastasis (CRLM). E.coli enhanced lactate production, which mediated M2 macrophage polarization by suppressing nuclear factor-κB -gene binding (NF-κB) signaling through retinoic acid-inducible gene 1 (RIG-I) lactylation. Lactylation of RIG-I suppressed recruitment of NF-κB to the Nlrp3 promoter in macrophages, thereby reducing its transcription. This loss of Nlrp3 affected the immunosuppressive activities of regulatory T cells (Tregs) and the antitumor activities of and CD8+ T cells. Small-molecule compound screening identified a RIG-I lactylation inhibitor that suppressed M2 polarization and sensitized CRLM to 5-fluorouracil (5-FU). Our findings suggest that tumor-resident microbiota may be a potential target for preventing and treating CRLM.

9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 789-793, 2024 Jun.
Article in Chinese | MEDLINE | ID: mdl-38926968

ABSTRACT

OBJECTIVE: To investigate the relative expression level and clinical significance of LINC00475 in serum of patients with multiple myeloma (MM). METHODS: The expression of LINC00475 in serum of 108 MM patients and five MM cell lines including RPMI 8226, NCI-H929, U266, OPM2 and CAG were detected by real-time fluorescence quantitative PCR. The diagnostic value of LINC00475 in MM was evaluated by receiver operating characteristic (ROC) curve analysis. The correlation of LINC00475 with patients' characteristics was analyzed. RESULTS: Compared with control groups, the expression of LINC00475 was up-regulated in serum of MM patients and MM cell lines (all P < 0.05). ROC curve analysis showed that the optimal cut-off value of LINC00475 was 262.4, the area under curve (AUC) was 0.924(95%CI : 0.884-0.964), and sensitivity and specificity was 83.3% and 91.7%, respectively, which indicated that LINC00475 had good evaluation value in MM patients. Compared with low-LINC00475 expression group, patients in high-LINC00475 expression group had higher levels of ß2microglobulin (ß2-MG) and Cystatin C (Cys-C) but lower albumin (ALB) (all P < 0.05). Compared with MM patients with International Staging System (ISS) stage I, the expression level of LINC00475 was significantly higher in patients with stage II and III (both P < 0.05). CONCLUSION: LINC00475 is helpful to distinguish MM patients from healthy adults, which is correlated with the prognostic indicators such as ß2-MG, ALB, and ISS stage.


Subject(s)
Multiple Myeloma , RNA, Long Noncoding , Humans , Multiple Myeloma/genetics , RNA, Long Noncoding/genetics , Cell Line, Tumor , beta 2-Microglobulin , ROC Curve , Clinical Relevance
10.
Biochim Biophys Acta Mol Basis Dis ; 1870(7): 167276, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38844114

ABSTRACT

The role of hypoxia in the tumor microenvironment of intrahepatic cholangiocarcinoma (iCCA) remains unclear. Here, we generated a comprehensive atlas of the entire tumor microenvironment and delineated the multifaceted cell-cell interactions to decipher hypoxia-induced pro-tumor immune suppression. We discovered hypoxia is significantly associated with iCCA progression via the activation of HIF1A expression. Moreover, hypoxia-dependent PPARγ-mediated fatty acid oxidation in APOE+ TAMs promoted M2 macrophage polarization by activating the HIF1A-PPARG-CD36 axis. These polarized APOE+ TAMs recruited Treg cell infiltration via the CCL3-CCR5 pair to form an immunosuppressive microenvironment. APOE+ TAMs tended to co-localize spatially with Treg cells in the malignant tissue based on spatial transcriptome data and immunofluorescence analysis results. We identified tumor-reactive CXCL13+ CD8-PreTex with specific high expression of ENTPD1 and ITGAE, which acted as precursors of CD8-Tex and had higher cytotoxicity, lower exhaustion, and more vigorous proliferation. Consequently, CXCL13+ CD8-PreTex functioned as a positive regulator of antitumor immunity by expressing the pro-inflammatory cytokines IFNG and TNF, associated with a better survival outcome. Our study reveals the mechanisms involved in hypoxia-induced immunosuppression and suggests that targeting precursor-exhausted CXCL13+CD8+ T cells might provide a pratical immunotherapeutic approach.

11.
Nanoscale ; 16(25): 12007-12012, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38805180

ABSTRACT

Polyvinyl alcohol (PVA) fiber materials have gained immense recognition due to their good biocompatibility and wide applications. However, methods allowing the synergistic enhancement of mechanical strength and toughness of PVA fibers still remain a key challenge. To this end, we developed covalently cross-linked ultrastrong SiO2-loaded polyvinyl alcohol fibers via a microfluidic spinning chemistry strategy. The thermal stretching and annealing processes not only promote the ordered arrangement of molecules, but also facilitate the ring opening reaction and increase crystallinity. Thus, the resulting fiber has a high tensile strength of 866 MPa, a specific toughness of 288 J g-1 and a tensile strain of 80%. This work provides a covalent cross-linking reinforcement method to prepare ultrastrong composite fibers assisted by microfluidic spinning chemistry and thermal stretching, which would lead to the fabrication of mechanically strong fiber materials through a simple pathway.

12.
Cartilage ; : 19476035241250198, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38747467

ABSTRACT

OBJECTIVE: Knee osteoarthritis (KOA) is a complex degenerative joint disease and a major cause of joint dysfunction. This study aimed to explore the function of hsa_circ_0007482 on inflammation, proliferation, differentiation, and apoptosis in KOA. DESIGN: Real-time quantitative polymerase chain reaction (PCR) was performed to detect the expression of circ_0007482, inflammatory factors, and differentiation-related molecules in KOA chondrocytes and interleukin (IL)-1ß-stimulated chondrocytes. The correlation between the circ_0007482 expression and inflammatory factors was analyzed by the Pearson method. KOA cell model was established using IL-1ß for 24 hours. The proliferation activity of chondrocytes was evaluated by CCK-8 assay, and cell apoptosis rate was assessed by flow cytometry. The downstream miRNA of circ_0007482 was validated using dual-luciferase reporter assay. RESULTS: The circ_0007482 expression was elevated in both KOA cartilage tissues and IL-1ß-treated chondrocytes and positively correlated with inflammatory factors expression. In comparison to the control group, IL-1ß treatment diminished chondrocyte proliferation abilities and increased cell apoptosis and inflammatory factors IL-6, IL-8, and tumor necrosis factor (TNF)-α mRNA expression. Inhibition of circ_0007482 partially improved IL-1ß-induced inflammatory reaction. Circ_0007482 could negatively regulate the expression of miR-558. CONCLUSIONS: Interfering of circ_0007482 might partially promote cell proliferation and differentiation, while inhibit cell apoptosis to improve joint injury by regulating miR-558 in IL-1ß-treated chondrocyte cell model.

13.
Plant Cell Environ ; 2024 May 21.
Article in English | MEDLINE | ID: mdl-38770581

ABSTRACT

Mitogen-activated protein kinase (MAPK) signalling cascades are functionally important signalling modules in eukaryotes. Transcriptome reprogramming of immune-related genes is a key process in plant immunity. Emerging evidence shows that plant MAPK cascade is associated with processing (P)-body components and contributes to transcriptome reprogramming of immune-related genes. However, it remains largely unknown how this process is regulated. Here, we show that OsMPK12, which is induced by Magnaporthe oryzae infection, positively regulates rice blast resistance. Further analysis revealed that OsMPK12 directly interacts with enhancer of mRNA decapping protein 4 (OsEDC4), a P-body-located protein, and recruits OsEDC4 to where OsMPK12 is enriched. Importantly, OsEDC4 directly interacts with two decapping complex members OsDCP1 and OsDCP2, indicating that OsEDC4 is a subunit of the mRNA decapping complex. Additionally, we found that OsEDC4 positively regulates rice blast resistance by regulating expression of immune-related genes and maintaining proper mRNA levels of some negatively-regulated genes. And OsMPK12 and OsEDC4 are also involved in rice growth and development regulation. Taken together, our data demonstrate that OsMPK12 positively regulates rice blast resistance via OsEDC4-mediated mRNA decay of immune-related genes, providing new insight into not only the new role of the MAPK signalling cascade, but also posttranscriptional regulation of immune-related genes.

14.
Clin Mol Hepatol ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38726504

ABSTRACT

Background/Aims: metabolic dysfunction-associated steatohepatitis (MASH) is an unmet clinical challenge due to the rapid increased occurrence but lacking approved drugs. Autophagy-related protein 16-like 1 (ATG16L1) plays an important role in the process of autophagy, which is indispensable for proper biogenesis of the autophagosome, but its role in modulating macrophage-related inflammation and metabolism during MASH has not been documented. Here, we aimed to elucidate the role of ATG16L1 in the progression of MASH. Methods: Expression analysis was performed with liver samples from human and mice. MASH models were induced in myeloid-specific Atg16l1-deficient and myeloid-specific Atg16l1-overexpressed mice by high-fat and high-cholesterol diet or methionine- and choline-deficient diet to explore the function and mechanism of macrophage ATG16L1 in MASH. Results: Macrophage-specific Atg16l1 knockout exacerbated MASH and inhibited energy expenditure, whereas macrophage-specific Atg16l1 transgenic overexpression attenuated MASH and promotes energy expenditure. Mechanistically, Atg16l1 knockout inhibited macrophage lipophagy, thereby suppressing macrophage ß-oxidation and decreasing the production of 4-hydroxynonenal (4-HNE), which further inhibited stimulator of interferon genes (STING) carbonylation. STING palmitoylation was enhanced, STING trafficking from the ER to the Golgi was promoted, and downstream STING signaling was activated, promoting proinflammatory and profibrotic cytokines secretion, resulting in hepatic steatosis and HSCs activation. Moreover, Atg16l1-deficiency enhanced macrophage phagosome ability but inhibited lysosome formation, engulfing mtDNA released by pyroptotic hepatocytes. Increased mtDNA promoted cGAS/STING signaling activation. Moreover, pharmacological promotion of ATG16L1 substantially blocked MASH progression. Conclusions: ATG16L1 suppresses MASH progression by maintaining macrophage lipophagy, restraining liver inflammation, and may be a promising therapeutic target for MASH management.

15.
Acta Pharmacol Sin ; 45(7): 1406-1424, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38589687

ABSTRACT

Acute kidney injury (AKI) is often accompanied by uremic encephalopathy resulting from accumulation of uremic toxins in brain possibly due to impaired blood-brain barrier (BBB) function. Anionic uremic toxins are substrates or inhibitors of organic anionic transporters (OATs). In this study we investigated the CNS behaviors and expression/function of BBB OAT3 in AKI rats and mice, which received intraperitoneal injection of cisplatin 8 and 20 mg/kg, respectively. We showed that cisplatin treatment significantly inhibited the expressions of OAT3, synaptophysin and microtubule-associated protein 2 (MAP2), impaired locomotor and exploration activities, and increased accumulation of uremic toxins in the brain of AKI rats and mice. In vitro studies showed that uremic toxins neither alter OAT3 expression in human cerebral microvascular endothelial cells, nor synaptophysin and MAP2 expressions in human neuroblastoma (SH-SY5Y) cells. In contrast, tumour necrosis factor alpha (TNFα) and the conditioned medium (CM) from RAW264.7 cells treated with indoxyl sulfate (IS) significantly impaired OAT3 expression. TNFα and CM from IS-treated BV-2 cells also inhibited synaptophysin and MAP2 expressions in SH-SY5Y cells. The alterations caused by TNFα and CMs in vitro, and by AKI and TNFα in vivo were abolished by infliximab, a monoclonal antibody designed to intercept and neutralize TNFα, suggesting that AKI impaired the expressions of OAT3, synaptophysin and MAP2 in the brain via IS-induced TNFα release from macrophages or microglia (termed as IS-TNFα axis). Treatment of mice with TNFα (0.5 mg·kg-1·d-1, i.p. for 3 days) significantly increased p-p65 expression and reduced the expressions of Nrf2 and HO-1. Inhibiting NF-κB pathway, silencing p65, or activating Nrf2 and HO-1 obviously attenuated TNFα-induced downregulation of OAT3, synaptophysin and MAP2 expressions. Significantly increased p-p65 and decreased Nrf2 and HO-1 protein levels were also detected in brain of AKI mice and rats. We conclude that AKI inhibits the expressions of OAT3, synaptophysin and MAP2 due to IS-induced TNFα release from macrophages or microglia. TNFα impairs the expressions of OAT3, synaptophysin and MAP2 partly via activating NF-κB pathway and inhibiting Nrf2-HO-1 pathway.


Subject(s)
Acute Kidney Injury , Cisplatin , Indican , Tumor Necrosis Factor-alpha , Animals , Acute Kidney Injury/metabolism , Tumor Necrosis Factor-alpha/metabolism , Humans , Mice , Male , RAW 264.7 Cells , Rats , Mice, Inbred C57BL , Organic Anion Transporters, Sodium-Independent/metabolism , Rats, Sprague-Dawley , Synaptophysin/metabolism , Blood-Brain Barrier/metabolism , Blood-Brain Barrier/drug effects , Uremia/metabolism , Uremia/complications , Cell Line, Tumor
16.
mSphere ; 9(5): e0005724, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38687129

ABSTRACT

Endocytosis has been extensively studied in yeasts, where it plays crucial roles in growth, signaling regulation, and cell-surface receptor internalization. However, the biological functions of endocytosis in pathogenic filamentous fungi remain largely unexplored. In this study, we aimed to functionally characterize the roles of EdeA, an ortholog of the Saccharomyces cerevisiae endocytic protein Ede1, in Aspergillus fumigatus. EdeA was observed to be distributed as patches on the plasma membrane and concentrated in the subapical collar of hyphae, a localization characteristic of endocytic proteins. Loss of edeA caused defective hyphal polarity, reduced conidial production, and fewer sites of endocytosis initiations than that of the parental wild type. Notably, the edeA null mutant exhibited increased sensitivity to cell wall-disrupting agents, indicating a role for EdeA in maintaining cell wall integrity in A. fumigatus. This observation was further supported by the evidence showing that the thickness of the cell wall in the ΔedeA mutant increased, accompanied by abnormal activation of MpkA, a key component in the cell wall integrity pathway. Additionally, the ΔedeA mutant displayed increased pathogenicity in the Galleria mellonella wax moth infection model, possibly due to alterations in cell wall morphology. Site-directed mutagenesis identified the conserved residue E348 within the third EH (Eps15 homology) domain of EdeA as crucial for its subcellular localization and functions. In conclusion, our results highlight the involvement of EdeA in endocytosis, hyphal polarity, cell wall integrity, and pathogenicity in A. fumigatus. IMPORTANCE: Aspergillus fumigatus is a significant human pathogenic fungus known to cause invasive aspergillosis, a disease with a high mortality rate. Understanding the basic principles of A. fumigatus pathogenicity is crucial for developing effective strategies against this pathogen. Previous research has underscored the importance of endocytosis in the infection capacity of pathogenic yeasts; however, its biological function in pathogenic mold remains largely unexplored. Our characterization of EdeA in A. fumigatus sheds light on the role of endocytosis in the development, stress response, and pathogenicity of pathogenic molds. These findings suggest that the components of the endocytosis process may serve as potential targets for antifungal therapy.


Subject(s)
Aspergillus fumigatus , Cell Wall , Endocytosis , Fungal Proteins , Hyphae , Aspergillus fumigatus/pathogenicity , Aspergillus fumigatus/genetics , Aspergillus fumigatus/metabolism , Cell Wall/metabolism , Cell Wall/genetics , Fungal Proteins/genetics , Fungal Proteins/metabolism , Hyphae/genetics , Hyphae/growth & development , Virulence , Animals , Moths/microbiology , Spores, Fungal/genetics , Spores, Fungal/pathogenicity , Aspergillosis/microbiology
17.
Article in English | MEDLINE | ID: mdl-38642326

ABSTRACT

BACKGROUND: Air volatile organic compounds (VOCs) cause allergic reaction mainly via the respiratory tract or skin. OBJECTIVE: This study aimed to investigate the association between daily visits by patients with urticaria and short-term changes in exposure to ambient air VOCs. METHODS: The dependent variable was information from patients with urticaria at a medical center in Kaohsiung, Taiwan, from 2014/01/01 to 2018/07/31. The multivariable model included one-day average 75th percentile values of air VOCs and meteorologic data retrieved from Taiwan Air Quality Monitoring Network database, and was analyzed using a case-crossover study design and conditional logistic regression. RESULTS: Total daily clinic visits for urticaria were significantly positively associated with higher levels of 4 VOCs (ethylbenzene, toluene, m-/p-xylene, and o-xylene (adjusted odds ratio (AOR: 1.03-1.28)) on the visit days, and 10 VOC levels on the fourth lag day (benzene, ethylbenzene, toluene, m-/p-xylene, o-xylene, 1,3,5-trimethylbenzene, n-hexane, methylcyclohexane, cyclohexane, and ethylene (AOR: 1.02-3.02)). Analyses of age and gender subgroups revealed that men showed resistance on the visit day, and women, older, and younger patients were more vulnerable. Men were influenced by higher benzene levels (AOR = 1.24) on the fourth lag day. Higher values of more than 6 VOCs on the fourth lag day significantly affected women, younger and older patients (AOR: 1.04-6.5). The most notable VOCs were methylcyclohexane (women AOR = 3.28, younger AOR = 3.82) and 1,3,5-trimethylbenzene (women AOR = 2.77, older AOR = 6.5) on the fourth lag day, which had the lowest concentrations but highest influence. CONCLUSION: The concentration of certain air VOCs significantly affected daily visits for urticaria.

18.
Synth Syst Biotechnol ; 9(2): 277-284, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38496318

ABSTRACT

Aspergillus niger is an efficient cell factory for organic acids production, particularly l-malic acid, through genetic manipulation. However, the traditional method of collecting A. niger spores for inoculation is labor-intensive and resource-consuming. In our study, we used the CRISPR-Cas9 system to replace the promoter of brlA, a key gene in Aspergillus conidiation, with a xylose-inducible promoter xylP in l-malic acid-producing A. niger strain RG0095, generating strain brlAxylP. When induced with xylose in submerged liquid culture, brlAxylP exhibited significant upregulation of conidiation-related genes. This induction allowed us to easily collect an abundance of brlAxylP spores (>7.1 × 106/mL) in liquid xylose medium. Significantly, the submerged conidiation approach preserves the substantial potential of A. niger as a foundational cellular platform for the biosynthesis of organic acids, including but not limited to l-malic acid. In summary, our study offers a simplified submerged conidiation strategy to streamline the preparation stage and reduce labor and material costs for industrial organic acid production using Aspergillus species.

19.
Appl Environ Microbiol ; 90(4): e0188523, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38451077

ABSTRACT

Histone acetyltransferase (HAT)-mediated epigenetic modification is essential for diverse cellular processes in eukaryotes. However, the functions of HATs in the human pathogen Aspergillus fumigatus remain poorly understood. In this study, we characterized the functions of MOZ, Ybf2/Sas3, Sas2, and Tip60 (MYST)-family histone acetyltransferase something about silencing (Sas3) in A. fumigatus. Phenotypic analysis revealed that loss of Sas3 results in significant impairments in colony growth, conidiation, and virulence in the Galleria mellonella model. Subcellular localization and Western blot analysis demonstrated that Sas3 localizes to nuclei and is capable of acetylating lysine 9 and 14 of histone H3 in vivo. Importantly, we found that Sas3 is critical for the cell wall integrity (CWI) pathway in A. fumigatus as evidenced by hypersensitivity to cell wall-perturbing agents, altered cell wall thickness, and abnormal phosphorylation levels of CWI protein kinase MpkA. Furthermore, site-directed mutagenesis studies revealed that the conserved glycine residues G641 and G643 and glutamate residue E664 are crucial for the acetylation activity of Sas3. Unexpectedly, only triple mutations of Sas3 (G641A/G643A/E664A) displayed defective phenotypes similar to the Δsas3 mutant, while double or single mutations did not. This result implies that the role of Sas3 may extend beyond histone acetylation. Collectively, our findings demonstrate that MYST-family HAT Sas3 plays an important role in the fungal development, virulence, and cell wall integrity in A. fumigatus. IMPORTANCE: Epigenetic modification governed by HATs is indispensable for various cellular processes in eukaryotes. Nonetheless, the precise functions of HATs in the human pathogen Aspergillus fumigatus remain elusive. In this study, we unveil the roles of MYST-family HAT Sas3 in colony growth, conidiation, virulence, and cell wall stress response in A. fumigatus. Particularly, our findings demonstrate that Sas3 can function through mechanisms unrelated to histone acetylation, as evidenced by site-directed mutagenesis experiments. Overall, this study broadens our understanding of the regulatory mechanism of HATs in fungal pathogens.


Subject(s)
Aspergillus fumigatus , Histone Acetyltransferases , Humans , Aspergillus fumigatus/genetics , Aspergillus fumigatus/metabolism , Histone Acetyltransferases/genetics , Histone Acetyltransferases/chemistry , Histone Acetyltransferases/metabolism , Histones/genetics , Histones/metabolism , Virulence , Cell Wall/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism
20.
Adv Sci (Weinh) ; 11(20): e2306297, 2024 May.
Article in English | MEDLINE | ID: mdl-38477534

ABSTRACT

Disrupted gastrointestinal (GI) motility is highly prevalent in patients with inflammatory bowel disease (IBD), but its potential causative role remains unknown. Herein, the role and the mechanism of impaired GI motility in colitis pathogenesis are investigated. Increased colonic mucosal inflammation is found in patients with chronic constipation (CC). Mice with GI dysmotility induced by genetic mutation or chemical insult exhibit increased susceptibility to colitis, dependent on the gut microbiota. GI dysmotility markedly decreases the abundance of Lactobacillus animlalis and increases the abundance of Akkermansia muciniphila. The reduction in L. animlalis, leads to the accumulation of linoleic acid due to compromised conversion to conjugated linoleic acid. The accumulation of linoleic acid inhibits Treg cell differentiation and increases colitis susceptibility via inducing macrophage infiltration and proinflammatory cytokine expression in macrophage. Lactobacillus and A. muciniphila abnormalities are also observed in CC and IBD patients, and mice receiving fecal microbiota from CC patients displayed an increased susceptibility to colitis. These findings suggest that GI dysmotility predisposes host to colitis development by modulating the composition of microbiota and facilitating linoleic acid accumulation. Targeted modulation of microbiota and linoleic acid metabolism may be promising to protect patients with motility disorder from intestinal inflammation.


Subject(s)
Colitis , Disease Models, Animal , Gastrointestinal Microbiome , Gastrointestinal Motility , Linoleic Acid , Animals , Gastrointestinal Microbiome/physiology , Mice , Linoleic Acid/metabolism , Colitis/metabolism , Colitis/microbiology , Colitis/chemically induced , Humans , Mice, Inbred C57BL , Male , Constipation/metabolism , Constipation/microbiology , Female , Akkermansia , Lactobacillus/metabolism
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