ABSTRACT
BACKGROUND: Recent numerous epidemiology and clinical association studies reported that ApoE polymorphism might be associated with the risk and severity of coronavirus disease 2019 (COVID-19), and yielded inconsistent results. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection relies on its spike protein binding to angiotensin-converting enzyme 2 (ACE2) receptor expressed on host cell membranes. METHODS: A meta-analysis was conducted to clarify the association between ApoE polymorphism and the risk and severity of COVID-19. Multiple protein interaction assays were utilized to investigate the potential molecular link between ApoE and the SARS-CoV-2 primary receptor ACE2, ApoE and spike protein. Immunoblotting and immunofluorescence staining methods were used to access the regulatory effect of different ApoE isoform on ACE2 protein expression. RESULTS: ApoE gene polymorphism (ε4 carrier genotypes VS non-ε4 carrier genotypes) is associated with the increased risk (P = 0.0003, OR = 1.44, 95% CI 1.18-1.76) and progression (P < 0.00001, OR = 1.85, 95% CI 1.50-2.28) of COVID-19. ApoE interacts with both ACE2 and the spike protein but did not show isoform-dependent binding effects. ApoE4 significantly downregulates ACE2 protein expression in vitro and in vivo and subsequently decreases the conversion of Ang II to Ang 1-7. CONCLUSIONS: ApoE4 increases SARS-CoV-2 infectivity in a manner that may not depend on differential interactions with the spike protein or ACE2. Instead, ApoE4 downregulates ACE2 protein expression and subsequently the dysregulation of renin-angiotensin system (RAS) may provide explanation by which ApoE4 exacerbates COVID-19 disease.
Subject(s)
COVID-19 , Humans , Renin-Angiotensin System/physiology , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme 2/pharmacology , SARS-CoV-2 , Apolipoprotein E4/genetics , Apolipoprotein E4/metabolism , Apolipoprotein E4/pharmacology , Down-Regulation/genetics , Spike Glycoprotein, Coronavirus/genetics , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolismABSTRACT
Botany-derived antimicrobial peptides (BAMPs), a class of small, cysteine-rich peptides produced in plants, are an important component of the plant immune system. Both in vivo and in vitro experiments have demonstrated their powerful antimicrobial activity. Besides in plants, BAMPs have cross-kingdom applications in human health, with toxic and/or inhibitory effects against a variety of tumor cells and viruses. With their diverse molecular structures, broad-spectrum antimicrobial activity, multiple mechanisms of action, and low cytotoxicity, BAMPs provide ideal backbones for drug design, and are potential candidates for plant protection and disease treatment. Lots of original research has elucidated the properties and antimicrobial mechanisms of BAMPs, and characterized their surface receptors and in vivo targets in pathogens. In this paper, we review and introduce five kinds of representative BAMPs belonging to the pathogenesis-related protein family, dissect their antifungal, antiviral, and anticancer mechanisms, and forecast their prospects in agriculture and global human health. Through the deeper understanding of BAMPs, we provide novel insights for their applications in broad-spectrum and durable plant disease prevention and control, and an outlook on the use of BAMPs in anticancer and antiviral drug design.
Subject(s)
Antimicrobial Peptides/genetics , Antimicrobial Peptides/metabolism , Antimicrobial Peptides/pharmacology , Agriculture , Anti-Infective Agents/pharmacology , Antimicrobial Cationic Peptides/pharmacology , Antiviral Agents/pharmacology , Drug Design/methods , Humans , Plant Immunity/drug effects , Plants/drug effects , Viruses/drug effectsABSTRACT
Cisplatin-based treatment is the standard of care therapy for urothelial carcinomas. However, complex cisplatin resistance mechanisms limit the success of this approach. Both apoptosis and autophagy have been shown to contribute to this resistance. Prodigiosin, a secondary metabolite from various bacteria, exerts different biological activities including the modulation of these two cellular stress response pathways. We analyzed the effect of prodigiosin on protein levels of different autophagy- and apoptosis-related proteins in cisplatin-sensitive and -resistant urothelial carcinoma cells (UCCs). Furthermore, we investigated the effect on cell viability of prodigiosin alone or in combination with cisplatin. We made use of four different pairs of cisplatin-sensitive and -resistant UCCs. We found that prodigiosin blocked autophagy in UCCs and re-sensitized cisplatin-resistant cells to apoptotic cell death. Furthermore, we found that prodigiosin is a potent anticancer agent with nanomolar IC50 values in all tested UCCs. In combination studies, we observed that prodigiosin sensitized both cisplatin-sensitive and -resistant urothelial carcinoma cell lines to cisplatin treatment with synergistic effects in most tested cell lines. These effects of prodigiosin are at least partially mediated by altering lysosomal function, since we detected reduced activities of cathepsin B and L. We propose that prodigiosin is a promising candidate for the therapy of cisplatin-resistant urothelial carcinomas, either as a single agent or in combinatory therapeutic approaches.
Subject(s)
Antineoplastic Agents/chemistry , Biological Products/chemistry , Prodigiosin/chemistry , Urinary Bladder Neoplasms/drug therapy , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Autophagy/drug effects , Biological Products/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Cisplatin/pharmacology , Drug Resistance, Neoplasm , Drug Synergism , Drug Therapy, Combination , Humans , Prodigiosin/pharmacologyABSTRACT
In hypoxic cells, dysfunctional mitochondria are selectively removed by a specialized autophagic process called mitophagy. The ER-mitochondrial contact site (MAM) is essential for fission of mitochondria prior to engulfment, and the outer mitochondrial membrane protein FUNDC1 interacts with LC3 to recruit autophagosomes, but the mechanisms integrating these processes are poorly understood. Here, we describe a new pathway mediating mitochondrial fission and subsequent mitophagy under hypoxic conditions. FUNDC1 accumulates at the MAM by associating with the ER membrane protein calnexin. As mitophagy proceeds, FUNDC1/calnexin association attenuates and the exposed cytosolic loop of FUNDC1 interacts with DRP1 instead. DRP1 is thereby recruited to the MAM, and mitochondrial fission then occurs. Knockdown of FUNDC1, DRP1, or calnexin prevents fission and mitophagy under hypoxic conditions. Thus, FUNDC1 integrates mitochondrial fission and mitophagy at the interface of the MAM by working in concert with DRP1 and calnexin under hypoxic conditions in mammalian cells.
Subject(s)
Calnexin/metabolism , Endoplasmic Reticulum/metabolism , GTP Phosphohydrolases/metabolism , Hypoxia , Membrane Proteins/metabolism , Microtubule-Associated Proteins/metabolism , Mitochondrial Dynamics , Mitochondrial Proteins/metabolism , Cells, Cultured , Dynamins , Humans , Mitophagy , Protein BindingABSTRACT
Heterogeneity in physical and chemical properties is a common characteristic in a subsurface environment. This study investigated the effect of physico-chemical heterogeneity on arsenic (As) sorption and reactive transport under water extraction in a layered system with preferential flow paths. A flume experiment was performed to derive the spatio-temporal data of As reactive transport. The results indicated that the heterogeneous system significantly accelerated downward (vertical direction) As migration as a coupled effect of physical and chemical heterogeneity that led to fast As transport with low As sorption along the preferential flow paths. The results also indicated that such a heterogeneity effect was driven by water extraction that enhanced the downward groundwater flow along the preferential flow paths. Numerical simulations were performed by matching the experimental results to provide insights into the dominant processes controlling the As migration in the heterogeneous systems. The simulation results highlighted the importance of the kinetic oxidation of mineral-bonded Fe(II) to Fe(III) in the clay matrix that dynamically increased As sorption affinity and retarded As reactive transport. A coupled model of reactive transport along the preferential flow paths, sorption-retarded diffusion from the preferential flow paths into the clay matrixes, and reactions that change sorption affinity in the matrix was required to describe the As reactive transport systems with physico-chemical heterogeneities. The results have strong implications for understanding and modeling As downward migration from shallow to deep aquifers under groundwater pumping conditions in field systems with inherent heterogeneity.
Subject(s)
Arsenic , Groundwater , Water Pollutants, Chemical , Arsenic/analysis , Diffusion , Ferric Compounds , Water , Water Pollutants, Chemical/analysisABSTRACT
AIMS AND OBJECTIVES: This research was conducted to explore the effectiveness of employing the healthcare failure mode and effect analysis method in the management of trial of labour after caesarean, with the aims of increasing vaginal birth after caesarean section rate and reducing potential risks that might cause severe complications. BACKGROUND: Previously high caesarean section rate in China and the "two children" policy leads to the situation where multiparas are faced with the choice of another caesarean or trial of labour after caesarean. Despite evidences showing the benefits of vaginal birth after caesarean, obstetricians and midwives in China tend to be conservative due to limited experience and insufficient clinical routines. Thus, its management needs further optimisation in order to make the practice safe and sound. DESIGN: A prospective quality improvement programme using the healthcare failure mode and effect analysis. METHODS: With the structured methodology of healthcare failure mode and effect analysis, we determined core processes of antepartum and intrapartum management, conducted risk priority numbers and devised remedial protocols for failure modes with high risks. The programme was then implemented as a clinical routine under the agreement of the institutional review board and vaginal birth after caesarean success rates were compared before and after the quality improvement programme, both descriptively and statistically. Standards for Quality Improvement Reporting Excellence 2.0 checklist was chosen on reporting the study process. RESULTS: Seventy failure modes in seven core processes were identified in the management process, with 14 redressed for actions. The 1-year follow-up trial of labour after caesarean and vaginal birth after caesarean rate was increased compared with the previous 3 years, with a vaginal birth after caesarean rate of 86.36%, whereas the incidence of uterine rupture was not compromised. CONCLUSIONS: The application of healthcare failure mode and effect analysis can not only promote trial of labour after caesarean and vaginal birth after caesarean rate, but also maintaining a low risk of uterine rupture. RELEVANCE TO CLINICAL PRACTICE: This modified vaginal birth after caesarean management protocol has been shown effective in increasing its successful rate, which can be continued for further comparison of severe complications to the previous practice.
Subject(s)
Healthcare Failure Mode and Effect Analysis , Trial of Labor , Vaginal Birth after Cesarean/statistics & numerical data , China , Female , Humans , Pregnancy , Prenatal Care/methods , Prospective Studies , Quality Improvement , Vaginal Birth after Cesarean/adverse effects , Vaginal Birth after Cesarean/nursingABSTRACT
Brown spot disease caused by Colletotrichum species was found on leaves of mulberry (Morus alba L.) in Dujiangyan, Sichuan Province, China. Fungal isolates from leaf lesions were identified as six Colletotrichum species based on morphological characteristics and DNA analysis of the combined sequences ITS, GAPDH, ACT, CHS-1, TUB2, and GS. These included Colletotrichum fioriniae, C. fructicola, C. cliviae, C. karstii, C. kahawae subsp. ciggaro, and C. brevisporum. Results showed that the most important causal agent of mulberry anthracnose was C. fioriniae, causing typical brown necrotic spots or streaks, followed by C. brevisporum, C. karstii, and C. kahawae subsp. ciggaro, whereas the two other species (C. fructicola and C. cliviae) showed no pathogenicity to mulberry. This study is the first report of these species associated with mulberry in China.
Subject(s)
Colletotrichum , Morus , Phylogeny , Virulence , China , Colletotrichum/pathogenicity , DNA, Fungal/genetics , Morus/microbiology , Plant Diseases/microbiology , Plant Leaves/microbiology , Species SpecificityABSTRACT
Assessment and characterization of gut microbiota has become a major research area in human disease, including type 2 diabetes, the most prevalent endocrine disease worldwide. To carry out analysis on gut microbial content in patients with type 2 diabetes, we developed a protocol for a metagenome-wide association study (MGWAS) and undertook a two-stage MGWAS based on deep shotgun sequencing of the gut microbial DNA from 345 Chinese individuals. We identified and validated approximately 60,000 type-2-diabetes-associated markers and established the concept of a metagenomic linkage group, enabling taxonomic species-level analyses. MGWAS analysis showed that patients with type 2 diabetes were characterized by a moderate degree of gut microbial dysbiosis, a decrease in the abundance of some universal butyrate-producing bacteria and an increase in various opportunistic pathogens, as well as an enrichment of other microbial functions conferring sulphate reduction and oxidative stress resistance. An analysis of 23 additional individuals demonstrated that these gut microbial markers might be useful for classifying type 2 diabetes.
Subject(s)
Diabetes Mellitus, Type 2/microbiology , Genome-Wide Association Study/methods , Intestines/microbiology , Metagenome/genetics , Metagenomics/methods , Asian People , Butyrates/metabolism , China/ethnology , Cohort Studies , Diabetes Mellitus, Type 2/classification , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/physiopathology , Feces/microbiology , Genetic Linkage/genetics , Genetic Markers , High-Throughput Nucleotide Sequencing , Humans , Metabolic Networks and Pathways/genetics , Opportunistic Infections/complications , Opportunistic Infections/microbiology , Reference Standards , Sulfates/metabolismABSTRACT
Autophagy eliminates dysfunctional mitochondria in an intricate process known as mitophagy. ULK1 is critical for the induction of autophagy, but its substrate(s) and mechanism of action in mitophagy remain unclear. Here, we show that ULK1 is upregulated and translocates to fragmented mitochondria upon mitophagy induction by either hypoxia or mitochondrial uncouplers. At mitochondria, ULK1 interacts with FUNDC1, phosphorylating it at serine 17, which enhances FUNDC1 binding to LC3. A ULK1-binding-deficient mutant of FUNDC1 prevents ULK1 translocation to mitochondria and inhibits mitophagy. Finally, kinase-active ULK1 and a phospho-mimicking mutant of FUNDC1 rescue mitophagy in ULK1-null cells. Thus, we conclude that FUNDC1 regulates ULK1 recruitment to damaged mitochondria, where FUNDC1 phosphorylation by ULK1 is crucial for mitophagy.
Subject(s)
Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/metabolism , Mitochondrial Proteins/metabolism , Mitophagy/physiology , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Autophagy-Related Protein-1 Homolog , Cell Hypoxia , HeLa Cells , Humans , Intracellular Signaling Peptides and Proteins/biosynthesis , Membrane Proteins/genetics , Microtubule-Associated Proteins/metabolism , Mitochondria/physiology , Mitochondrial Proteins/genetics , Mutation , Phosphorylation , Protein Binding , Protein Serine-Threonine Kinases/biosynthesis , Up-RegulationABSTRACT
Mitophagy receptors mediate the selective recognition and targeting of damaged mitochondria by autophagosomes. The mechanism for the regulation of these receptors remains unknown. Here, we demonstrated that a novel hypoxia-responsive microRNA, microRNA-137 (miR-137), markedly inhibits mitochondrial degradation by autophagy without affecting global autophagy. miR-137 targets the expression of two mitophagy receptors NIX and FUNDC1. Impaired mitophagy in response to hypoxia caused by miR-137 is reversed by re-expression of FUNDC1 and NIX expression vectors lacking the miR-137 recognition sites at their 3' UTR. Conversely, miR-137 also suppresses the mitophagy induced by fundc1 (CDS+3'UTR) but not fundc1 (CDS) overexpression. Finally, we found that miR-137 inhibits mitophagy by reducing the expression of the mitophagy receptor thereby leads to inadequate interaction between mitophagy receptor and LC3. Our results demonstrated the regulatory role of miRNA to mitophagy receptors and revealed a novel link between miR-137 and mitophagy.
Subject(s)
Autophagy , Membrane Proteins/metabolism , MicroRNAs/metabolism , Mitochondrial Proteins/metabolism , 3' Untranslated Regions , Animals , Cell Hypoxia , Fibroblasts/metabolism , Gene Expression Regulation , Genetic Vectors , HEK293 Cells , HeLa Cells , Humans , Mice , Mice, Inbred C57BL , Mitochondria/metabolism , Phagosomes/metabolismABSTRACT
HxTx-Hv1h, a neurotoxic peptide derived from spider venom, has been developed for use in commercial biopesticide formulations. Cell Penetrating Peptides (CPPs) are short peptides that facilitate the translocation of various biomolecules across cellular membranes. Here, we evaluated the aphidicidal efficacy of a conjugated peptide, HxTx-Hv1h/CPP-1838, created by fusing HxTx-Hv1h with CPP-1838. Additionally, we aimed to establish a robust recombinant expression system for HxTx-Hv1h/CPP-1838. We successfully achieved the secretory production of HxTx-Hv1h, its fusion with Galanthus nivalis agglutinin (GNA) forming HxTx-Hv1h/GNA and HxTx-Hv1h/CPP-1838 in yeast. Purified HxTx-Hv1h exhibited contact toxicity against Megoura crassicauda, with a 48 h median lethal concentration (LC50) of 860.5 µg/mL. Fusion with GNA or CPP-1838 significantly enhanced its aphidicidal potency, reducing the LC50 to 683.5 µg/mL and 465.2 µg/mL, respectively. The aphidicidal efficacy was further improved with the addition of surfactant, decreasing the LC50 of HxTx-Hv1h/CPP-1838 to 66.7 µg/mL-over four times lower compared to HxTx-Hv1h alone. Furthermore, we engineered HxTx-Hv1h/CPP-1838 multi-copy expression vectors utilizing the BglBrick assembly method and achieved high-level recombinant production in laboratory-scale fermentation. This study is the first to document a CPP fusion strategy that enhances the transdermal aphidicidal activity of a natural toxin like HxTx-Hv1h and opens up the possibility of exploring the recombinant production of HxTx-Hv1h/CPP-1838 for potential applications.
Subject(s)
Cell-Penetrating Peptides , Neurotoxins , Spider Venoms , Spider Venoms/chemistry , Spider Venoms/genetics , Spider Venoms/toxicity , Animals , Cell-Penetrating Peptides/pharmacology , Cell-Penetrating Peptides/chemistry , Neurotoxins/toxicity , Neurotoxins/pharmacology , Neurotoxins/genetics , Plant Lectins/pharmacology , Plant Lectins/genetics , Plant Lectins/chemistry , Insecticides/pharmacology , Insecticides/toxicityABSTRACT
Short-chain fatty acids (SCFAs) have been increasingly evidenced to be important bioactive metabolites of the gut microbiota and transducers in controlling diverse psychiatric or neurological disorders via the microbiota-gut-brain axis. However, the precise mechanism by which brain SCFAs extert multiple beneficial effects is not completely understood. Our previous research has demonstrated that the acetyl-coenzyme A synthetase short-chain family member 2 (ACSS2) is a novel target of the rapid and long-lasting antidepressant responses. Here, we show that micromolar SCFAs significantly augment both total cellular and nuclear ACSS2 to trigger tryptophan hydroxylase 2 (TPH2) promoter histone acetylation and its transcription in SH-SY5Y cells. In chronic-restraint-stress-induced depression mice, neuronal ACSS2 knockdown by stereotaxic injection of adeno-associated virus in the hippocampus abolished SCFA-mediated improvements in depressive-like behaviors of mice, supporting that ACSS2 is required for SCFA-mediated antidepressant responses. Mechanistically, the peroxisome-proliferator-activated receptor gamma (PPARγ) is identified as a novel partner of ACSS2 to activate TPH2 transcription. Importantly, PPARγ is also responsible for SCFA-mediated antidepressant-like effects via ACSS2-TPH2 axis. To further support brain SCFAs as a therapeutic target for antidepressant effects, d-mannose, which is a naturally present hexose, can significantly reverse the dysbiosis of gut microbiota in the chronic-restraint-stress-exposure mice and augment brain SCFAs to protect against the depressive-like behaviors via ACSS2-PPARγ-TPH2 axis. In summary, brain SCFAs can activate ACSS2-PPARγ-TPH2 axis to play the antidepressive-like effects, and d-mannose is suggested to be an inducer of brain SCFAs in resisting depression.
ABSTRACT
According to the latest evidence, the microbial metabolite Urolithin A (UA), known for its role in promoting cellular health, modulates CD8+ T cell-mediated antitumor activity. However, the direct target protein of UA and its underlying mechanism remains unclear. Here, this research identifies ERK1/2 as the specific target crucial for UA-mediated CD8+ T cell activation. Even at low doses, UA markedly enhances the persistence and effector functions of primary CD8+ cytotoxic T lymphocytes (CTLs) and human chimeric antigen receptor (CAR) T cells both in vitro and in vivo. Mechanistically, UA interacts directly with ERK1/2 kinases, enhancing their activation and subsequently facilitating T cell activation by engaging ULK1. The UA-ERK1/2-ULK1 axis promotes autophagic flux in CD8+ CTLs, enhancing cellular metabolism and maintaining reactive oxygen species (ROS) levels, as evidenced by increased oxygen consumption and extracellular acidification rates. UA-treated CD8+ CTLs also display elevated ATP levels and enhanced spare respiratory capacity. Overall, UA activates ERK1/2, inducing autophagy and metabolic adaptation, showcasing its potential in tumor immunotherapy and interventions for diseases involving ERKs.
Subject(s)
Autophagy-Related Protein-1 Homolog , CD8-Positive T-Lymphocytes , Coumarins , Animals , Humans , Mice , Autophagy/immunology , Autophagy-Related Protein-1 Homolog/drug effects , Autophagy-Related Protein-1 Homolog/genetics , Autophagy-Related Protein-1 Homolog/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Coumarins/pharmacology , Coumarins/metabolism , Disease Models, Animal , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/immunology , Mice, Inbred C57BL , Neoplasms/immunology , Neoplasms/therapy , Neoplasms/metabolismABSTRACT
OBJECTIVES: This study aimed to analyse the experiences and feelings of patients with type A aortic dissection (TAAD) and their families during the medical treatment and referral process, investigate the entire process's needs and problems and provide evidence for improving the aortic dissection treatment system. DESIGN: A qualitative descriptive design using a phenomenological study. Face-to-face semistructured interviews were conducted. Thematic analysis was used to analyse the interview data, which was transcribed verbatim. SETTING: Department of Cardiovascular Surgery of Shanxi Bethune Hospital in China. PARTICIPANTS: Fifteen family groups, consisting of patients with TAAD who underwent surgical treatment and their families, were selected. RESULTS: Three primary themes were discussed and developed. Theme 1: the experiences of medical treatment and referral (confusion at the onset; complex inner feelings and emotional expressions of the medical treatment and referral; preoperative inner conflict); theme 2: problems with the TAAD medical treatment system (the quality of diagnosis and medical treatment needs to be improved; deficiency of medical system policies and procedures); and theme 3: real demands (demands for TAAD-related knowledge and access to the disease; economic-related demands). CONCLUSION: Patients with TAAD and their families encounter complex inner experiences, multiple requirements and numerous challenges during the medical treatment and referral process. It is advised that the treatment and referral system of TAAD in China needs to be improved. Future research and clinical practice should standardise diagnosis and treatment training, establish a fast channel for TAAD to prioritise treatment, popularise aortic dissection-related knowledge and improve the funding system.
Subject(s)
Aortic Dissection , Patients , Humans , Qualitative Research , Aortic Dissection/surgery , Referral and ConsultationABSTRACT
Ligusticum chuanxiong Hort. (Chuanxiong) is an important Chinese medicinal herb, whose rhizomes are widely used as raw materials for treating various diseases caused by blood stasis. The fresh tender stems and leaves of Chuanxiong are also consumed and have the potential as microgreens. Here, we investigated the effect of light spectra on yield and total flavonoid content of Chuanxiong microgreens by treatment with LED-based white light (WL), red light (RL), blue light (BL), and continuous darkness (DD). The results showed that WL and BL reduced biomass accumulation but significantly increased total flavonoid content compared to RL or DD treatments. Widely targeted metabolomics analysis confirmed that BL promoted the accumulation of flavones and flavonols in Chuanxiong microgreens. Further integration of transcriptomics and metabolomics analysis revealed the mechanism by which BL induces the up-regulation of transcription factors such as HY5 and MYBs, promotes the expression of key genes targeted for flavonoid biosynthesis, and ultimately leads to the accumulation of flavones and flavonols. This study suggests that blue light is a proper light spectra to improve the quality of Chuanxiong microgreens, and the research results lay a foundation for guiding the de-etiolation of Chuanxiong microgreens to obtain both yield and quality in production practice.
Subject(s)
Flavones , Ligusticum , Flavonols , Transcriptome , Flavonoids , MetabolomicsABSTRACT
INTRODUCTION: During the arms race between plants and pathogens, pathogenesis-related proteins (PR) in host plants play a crucial role in disease resistance, especially PR1. PR1 constitute a secretory peptide family, and their role in plant defense has been widely demonstrated in both hosts and in vitro. However, the mechanisms by which they control host-pathogen interactions and the nature of their targets within the pathogen remain poorly understood. OBJECTIVES: The present study was aimed to investigate the anti-oomycete activity of secretory PR1 proteins and elaborate their underlying mechanisms. METHODS: This study was conducted in the potato-Phytophthora infestans pathosystem. After being induced by the pathogen infection, the cross-kingdom translocation of secretory PR1 was demonstrated by histochemical assays and western blot, and their targets in P. infestans were identified by yeast-two-hybrid assays, bimolecular fluorescence complementation assays, and co-immunoprecipitation assay. RESULTS: The results showed that the expression of secretory PR1-encoding genes was induced during pathogen infection, and the host could deliver PR1 into P. infestans to inhibit its vegetative growth and pathogenicity. The translocated secretory PR1 targeted the subunits of the AMPK kinase complex in P. infestans, thus affecting the AMPK-driven phosphorylation of downstream target proteins, preventing ROS homeostasis, and down-regulating the expression of RxLR effectors. CONCLUSION: The results provide novel insights into the molecular function of PR1 in protecting plants against pathogen infection, and uncover a potential target for preventing pre- and post-harvest late blight.
Subject(s)
AMP-Activated Protein Kinase Kinases , Phytophthora infestans , Plants , Phytophthora infestans/genetics , Host-Pathogen Interactions , Disease Resistance/geneticsABSTRACT
Viruses typically hijack the cellular machinery of their hosts for successful infection and replication, while the hosts protect themselves against viral invasion through a variety of defense responses, including autophagy, an evolutionarily ancient catabolic pathway conserved from plants to animals. Double-membrane vesicles called autophagosomes transport trapped viral cargo to lysosomes or vacuoles for degradation. However, during an ongoing evolutionary arms race, viruses have acquired a strong ability to disrupt or even exploit the autophagy machinery of their hosts for successful invasion. In this review, we analyze the universal role of autophagy in antiviral defenses in animals and plants and summarize how viruses evade host immune responses by disrupting and manipulating host autophagy. The review provides novel insights into the role of autophagy in virus-host interactions and offers potential targets for the prevention and control of viral infection in both plants and animals.
Subject(s)
Virus Diseases , Viruses , Animals , Autophagosomes , Autophagy , Host-Pathogen Interactions , Immunity, Innate , Virus ReplicationABSTRACT
The evolutionarily conserved ULK1 kinase complex acts as gatekeeper of canonical autophagy and regulates induction of autophagosome biogenesis. To better understand control of ULK1 and analyze whether ULK1 has broader functions that are also linked to the later steps of autophagy, we perform comprehensive phosphoproteomic analyses. Combining in vivo with in vitro data, we identify numerous direct ULK1 target sites within autophagy-relevant proteins that are critical for autophagosome maturation and turnover. In addition, we highlight an intimate crosstalk between ULK1 and several phosphatase complexes. ULK1 is not only a PP2A target but also directly phosphorylates the regulatory PP2A subunit striatin, activating PP2A and serving as positive feedback to promote autophagy-dependent protein turnover. Thus, ULK1 and phosphatase activities are tightly coordinated to robustly regulate protein degradation by autophagy.
Subject(s)
Autophagy-Related Protein-1 Homolog/metabolism , Autophagy/physiology , Calmodulin-Binding Proteins/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/metabolism , Nerve Tissue Proteins/metabolism , Protein Phosphatase 2/metabolism , Autophagosomes/metabolism , Autophagy-Related Proteins/metabolism , Humans , Phosphorylation , Protein Processing, Post-Translational/physiologyABSTRACT
Ferroptosis is a form of regulated cell death that emerges to be relevant for therapy-resistant and dedifferentiating cancers. Although several lines of evidence suggest that ferroptosis is a type of autophagy-dependent cell death, the underlying molecular mechanisms remain unclear. Fin56, a type 3 ferroptosis inducer, triggers ferroptosis by promoting glutathione peroxidase 4 (GPX4) protein degradation via a not fully understood pathway. Here, we determined that Fin56 induces ferroptosis and autophagy in bladder cancer cells and that Fin56-triggered ferroptosis mechanistically depends on the autophagic machinery. Furthermore, we found that autophagy inhibition at different stages attenuates Fin56-induced oxidative stress and GPX4 degradation. Moreover, we investigated the effects of Fin56 in combination with Torin 2, a potent mTOR inhibitor used to activate autophagy, on cell viability. We found that Fin56 synergizes with Torin 2 in cytotoxicity against bladder cancer cells. Collectively, our findings not only support the concept that ferroptosis is a type of autophagy-dependent cell death but imply that the combined application of ferroptosis inducers and mTOR inhibitors is a promising approach to improve therapeutic options in the treatment of bladder cancer.