ABSTRACT
The multi-pass transmembrane protein ACCELERATED CELL DEATH 6 (ACD6) is an immune regulator in Arabidopsis thaliana with an unclear biochemical mode of action. We have identified two loci, MODULATOR OF HYPERACTIVE ACD6 1 (MHA1) and its paralog MHA1-LIKE (MHA1L), that code for â¼7 kDa proteins, which differentially interact with specific ACD6 variants. MHA1L enhances the accumulation of an ACD6 complex, thereby increasing the activity of the ACD6 standard allele for regulating plant growth and defenses. The intracellular ankyrin repeats of ACD6 are structurally similar to those found in mammalian ion channels. Several lines of evidence link increased ACD6 activity to enhanced calcium influx, with MHA1L as a direct regulator of ACD6, indicating that peptide-regulated ion channels are not restricted to animals.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Ankyrins/metabolism , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cell Death , Ion Channels/genetics , Ion Channels/metabolism , Plant Immunity/geneticsABSTRACT
BACKGROUND: The sucrose nonfermenting-1-related protein kinase 2 (SnRK2) plays a crucial role in responses to diverse biotic/abiotic stresses. Currently, there are reports on these genes in Haynaldia villosa, a diploid wild relative of wheat. RESULTS: To understand the evolution of SnRK2-V family genes and their roles in various stress conditions, we performed genome-wide identification of the SnRK2-V gene family in H. villosa. Ten SnRK2-V genes were identified and characterized for their structures, functions and spatial expressions. Analysis of gene exon/intron structure further revealed the presence of evolutionary paths and replication events of SnRK2-V gene family in the H. villosa. In addition, the features of gene structure, the chromosomal location, subcellular localization of the gene family were investigated and the phylogenetic relationship were determined using computational approaches. Analysis of cis-regulatory elements of SnRK2-V gene members revealed their close correlation with different phytohormone signals. The expression profiling revealed that ten SnRK2-V genes expressed at least one tissue (leave, stem, root, or grain), or in response to at least one of the biotic (stripe rust or powdery mildew) or abiotic (drought or salt) stresses. Moreover, SnRK2.9-V was up-regulated in H. villosa under the drought and salt stress and overexpressing of SnRK2.9-V in wheat enhanced drought and salt tolerances via enhancing the genes expression of antioxidant enzymes, revealing a potential value of SnRK2.9-V in wheat improvement for salt tolerance. CONCLUSION: Our present study provides a basic genome-wide overview of SnRK2-V genes in H. villosa and demonstrates the potential use of SnRK2.9-V in enhancing the drought and salt tolerances in common wheat.
Subject(s)
Salt Tolerance , Triticum , Triticum/metabolism , Salt Tolerance/genetics , Protein Kinases/genetics , Droughts , Phylogeny , Poaceae/genetics , Salt Stress/genetics , Stress, Physiological/genetics , Gene Expression Regulation, Plant , Plant Proteins/genetics , Plant Proteins/metabolismABSTRACT
Maize is one of the most important crops for food, cattle feed and energy production. However, maize is frequently attacked by various pathogens and pests, which pose a significant threat to maize yield and quality. Identification of quantitative trait loci and genes for resistance to pests will provide the basis for resistance breeding in maize. Here, a ß-glucosidase ZmBGLU17 was identified as a resistance gene against Pythium aphanidermatum, one of the causal agents of corn stalk rot, by genome-wide association analysis. Genetic analysis showed that both structural variations at the promoter and a single nucleotide polymorphism at the fifth intron distinguish the two ZmBGLU17 alleles. The causative polymorphism near the GT-AG splice site activates cryptic alternative splicing and intron retention of ZmBGLU17 mRNA, leading to the downregulation of functional ZmBGLU17 transcripts. ZmBGLU17 localizes in both the extracellular matrix and vacuole and contribute to the accumulation of two defence metabolites lignin and DIMBOA. Silencing of ZmBGLU17 reduces maize resistance against P. aphanidermatum, while overexpression significantly enhances resistance of maize against both the oomycete pathogen P. aphanidermatum and the Asian corn borer Ostrinia furnacalis. Notably, ZmBGLU17 overexpression lines exhibited normal growth and yield phenotype in the field. Taken together, our findings reveal that the apoplastic and vacuolar localized ZmBGLU17 confers resistance to both pathogens and insect pests in maize without a yield penalty, by fine-tuning the accumulation of lignin and DIMBOA.
Subject(s)
Zea mays , beta-Glucosidase , Animals , Cattle , Zea mays/genetics , Zea mays/chemistry , beta-Glucosidase/genetics , Genome-Wide Association Study , Lignin , Plant Breeding , InsectaABSTRACT
BACKGROUND AND AIMS: Lysyl oxidase-like 1 (LOXL1) proteins are amine oxidases that play a crucial role in extracellular matrix remodeling due to their collagen cross-linking and intracellular functions. The role of LOXL1 in cholestatic liver fibrosis remains unexplored. METHODS: We measured LOXL1 expression in two murine models of cholestasis (Mdr2 knockout [Mdr2-/-] and bile duct ligation [BDL]). We used adeno-associated virus (AAV) serotype 6-mediated hepatic delivery against LOXL1 (AAV2/6-shLoxl1) to investigate the therapeutic efficacy of targeting LOXL1 in cholestatic liver fibrosis. NIH-3T3 murine fibroblasts were used to investigate the function and regulatory mechanisms of LOXL1 in vitro. RESULTS: LOXL1 expression was significantly upregulated in Mdr2 -/- and BDL mice compared to their corresponding controls, predominantly in collagen-rich fibrous septa and portal areas. AAV2/6-shLoxl1 significantly reduced LOXL1 levels in Mdr2-/- and BDL mice, mainly located in desmin-positive hepatic stellate cells (HSCs) and fibroblasts. Concomitant with reduced LOXL1 expression, there was reduced ductular reaction, inflammation, and fibrosis in both Mdr2 -/- and BLD mouse models. Additionally, Loxl1 intervention decreased Ki-67 positive cells in the desmin-positive areas in both Mdr2 -/- and BDL mice. Overexpression of LOXL1 significantly promoted fibroblast proliferation by activating the platelet-derived growth factor receptor and extracellular signal-regulated kinase signaling pathways in vitro. CONCLUSION: Our findings demonstrated that selective inhibition of LOXL1 derived from HSCs/fibroblasts attenuated cholestatic liver/biliary fibrosis, inflammation, ductal reaction, and HSC/fibroblast proliferation. Based on our findings LOXL1 could be a potential therapeutic target for cholestatic fibrosis.
ABSTRACT
BACKGROUND: Postoperative ileus (POI) is characterized by the activation of inflammation triggered by tissue damage. Damage-associated molecular patterns (DAMPs) reportedly induce local inflammation after injury. However, the impact of DAMPs on intestinal resident lymphocytes during POI remains poorly elucidated. METHODS: POI in mice was induced via intestinal manipulation (IM). The concentration of nicotinamide adenine dinucleotide (NAD) was detected after IM. The gastrointestinal motility of the mice was assessed after IM or NAD injection. Cytokine production and calcium influx in T cells were investigated after NAD stimulation using flow cytometry. RESULTS: The concentration of extracellular NAD significantly increased after IM administration, and NAD directly impaired gastrointestinal motility. Intraperitoneal injection of NAD promoted the expression of TNF-α in intestinal CD8+ and CD4+ T cells, but only IFN-γ production by CD8+ T cells was significantly promoted by NAD injection. Granzyme B production in CD8+ and CD4+ T cells decreased after administration. Concordantly, the same results were observed in NAD stimulation of intestinal CD3+ T cells in vitro. Blocking the P2X7R-related membrane enzyme ART2.2 significantly diminished the pro-inflammatory effect of NAD. CONCLUSION: IM includes the release of NAD derived from damaged tissues, consequently promoting pro-inflammatory cytokine production in intestinal CD4+ and CD8+ T lymphocytes. NAD-induced intestinal T cells activation may be associated with POI progression in the mouse.
Subject(s)
Ileus , NAD , Mice , Animals , Ileus/metabolism , Inflammation/metabolism , Postoperative Complications/metabolism , Cytokines , CD8-Positive T-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/metabolismABSTRACT
Objective To investigate the role of ATP citrate lyase(ACLY)in the development of hepatocellular carcinoma(HCC)and the impact of this enzyme on the immune microenvironment of HCC.Methods We utilized the University of Alabama at Birmingham Cancer Data Analysis Portal and the Gene Expression Profiling Interactive Analysis to identify the changes in ACLY expression and prognosis across different tumor types from The Cancer Genome Atlas.With HCC as the disease model,we analyzed the ACLY expression in HCC samples from the gene expression database.Furthermore,we collected the clinical specimens from HCC patients to verify the mRNA and protein levels of ACLY.In addition,we conducted transcriptome sequencing after knocking down the expression of ACLY to analyze the differentially expressed genes and investigated the impact of ACLY expression interference on cell proliferation and other functions.Finally,we explored the correlations of ACLY with immune cells and immune infiltration in the tumor microenvironment,new antigens,and immune checkpoint genes.Results ACLY expression was significantly up-regulated in solid tumors including HCC(all P<0.05),and high ACLY expression was associated with overall survival rate in HCC(P=0.005).Furthermore,high ACLY expression affected the presence of immune cells(e.g.,tumor-associated fibroblasts)and the expression of genes involved in lipid metabolism(all P<0.05).Conclusions ACLY is closely related to the occurrence and development of HCC and lipid metabolism abnormalities.Moreover,it has a specific impact on the immune microenvironment of HCC.
Subject(s)
ATP Citrate (pro-S)-Lyase , Carcinoma, Hepatocellular , Liver Neoplasms , Humans , ATP Citrate (pro-S)-Lyase/genetics , ATP Citrate (pro-S)-Lyase/metabolism , Clinical Relevance , Lipid Metabolism , Tumor MicroenvironmentABSTRACT
Necrosis- and ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs) constitute a superfamily of proteins toxic to dicot plants, but the molecular basis of this toxicity remains obscure. Using quantitative trait locus (QTL) analysis we investigated the genetic variation underlying ion leakage in Arabidopsis plants elicited with MoNLP1 derived from Magnaporthe oryzae. The QTL conditioning MoNLP1 toxicity was positionally cloned and further characterized to elucidate its mode of action. MoNLP1-triggered cell death varied significantly across > 250 Arabidopsis accessions and three QTLs were identified conferring the observed variation. The QTL on chromosome 4 was uncovered to encode a leucine-rich repeat (LRR)-only protein designated as NTCD4, which shares high sequence identity with a set of nucleotide-binding LRR proteins. NTCD4 was secreted into the apoplast and physically interacted with multiple NLPs. Apoplastic NTCD4 facilitated the oligomerization of NLP, which was closely associated with toxicity in planta. The natural genetic variation causing D3N change in NTCD4 reduced the secretion efficiency of NTCD4 and the infection of Botrytis cinerea on Arabidopsis plants. These observations demonstrate that the plant-derived NTCD4 is recruited by NLPs to promote toxicity via facilitating their oligomerization, which extends our understanding of a key step in the toxic mode of action of NLPs.
Subject(s)
Arabidopsis , Arabidopsis/genetics , Ascomycota , Botrytis , Cell Death , Disease Susceptibility , Plant DiseasesABSTRACT
BACKGROUND: Bariatric surgery may be indicated in patients with nonalcoholic fatty liver disease (NAFLD) to achieve and maintain the degree of weight loss required to ensure therapeutic effects. However, bariatric surgery is still underrecognized in the treatment of NAFLD, including its inflammatory subtype, nonalcoholic steatohepatitis (NASH). Moreover, there is a lack of follow-up outcome data on different types of bariatric surgery in patients with NAFLD. This study aims to adequately assess the effect of bariatric surgery on NAFLD remission in obese patients. METHODS: This prospective multicentre observational follow-up study will include 142 obese patients with NAFLD scheduled to undergo one of the following surgical procedures: sleeve gastrostomy, Roux-en-Y gastric bypass, and one anastomosis gastric bypass. The primary outcome is the complete remission rate of NAFLD one year postoperatively, which is defined by liver fat fraction < 5% on magnetic resonance imaging; the secondary outcomes includes (i) changes in NASH and liver fibrosis biopsy findings, (ii) changes in body weight and abdominal adipose weight, (iii) resolution of obesity-related comorbidities, and (iv) incidence of adverse events. A long-term follow-up related to this study will also be conducted. DISCUSSION: This study will provide a necessary and preliminary foundation for the early identification and targeted treatment of patients with NAFLD who can be referred for bariatric surgery, as indicated for management of obesity and metabolic disease. TRIAL REGISTRATION: Clinicaltrials.gov: NCT04366999. Registered 21 April 2020. ( https://clinicaltrials.gov/ct2/show/NCT04366999 ).
Subject(s)
Bariatric Surgery , Gastric Bypass , Non-alcoholic Fatty Liver Disease , Obesity, Morbid , Follow-Up Studies , Humans , Multicenter Studies as Topic , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/surgery , Obesity/complications , Obesity/surgery , Observational Studies as Topic , Prospective Studies , Treatment OutcomeABSTRACT
Wheat powdery mildew (Pm), caused by Blumeria graminis f. sp. tritici (Bgt), is a prevalent fungal disease. The diploid wheat relative Haynaldia villosa (H. villosa) showed broad-spectrum resistance (BSR) to Pm. A previous study reported an E3 ligase gene, CMPG1-V from H. villosa, showing BSR to Pm. To elucidate the regulatory network mediated by CMPG1-V, in this study, gene expression profiling of CMPG1-V transgenic plant (CMPG1-VOE) and its receptor Yangmai 158 was analyzed and compared after Bgt inoculation at four infection stages. GO and KEGG analysis revealed obvious reprogramming of SA and ABA signaling, starch/sucrose metabolism, and photosynthesis in CMPG1-VOE, compared with those in Yangmai 158. Transcripts of SA synthesis genes SARD1 and UGT, signaling factors TGA and PRs, and SnRKs in ABA signaling were specifically upregulated in CMPG1-VOE rather than Yangmai 158. Transcripts of LHCII in photosynthesis, GLUC and TPP in starch/sucrose metabolism were also induced distinctly in CMPG1-VOE. WGCNA analysis showed crucial regulatory candidates of CMPG1-V, involving serine/threonine-protein kinase in phosphorylation, glucosyltransferase in flavonoid biosynthesis, defense factor WRKYs, and peroxidase in oxidative stress. Our results facilitate the deciphering of the resistant regulatory network of CMPG1-V and the identification of key candidates which might be employed in breeding programs.
Subject(s)
Ascomycota/pathogenicity , Disease Resistance , Gene Regulatory Networks , Plant Proteins/metabolism , Triticum/genetics , Ubiquitin-Protein Ligases/metabolism , Abscisic Acid/metabolism , Gene Expression Regulation, Plant , Plant Proteins/genetics , Salicylic Acid/metabolism , Sucrose/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Transcriptome , Transgenes , Triticum/microbiology , Ubiquitin-Protein Ligases/geneticsABSTRACT
Plants deploy intracellular receptors to counteract pathogen effectors that suppress cell-surface-receptor-mediated immunity. To what extent pathogens manipulate intracellular receptor-mediated immunity, and how plants tackle such manipulation, remains unknown. Arabidopsis thaliana encodes three similar ADR1 class helper nucleotide-binding domain leucine-rich repeat receptors (ADR1, ADR1-L1, and ADR1-L2), which are crucial in plant immunity initiated by intracellular receptors. Here, we report that Pseudomonas syringae effector AvrPtoB suppresses ADR1-L1- and ADR1-L2-mediated cell death. ADR1, however, evades such suppression by diversifying into two ubiquitination sites targeted by AvrPtoB. The intracellular sensor SNC1 interacts with and guards the CCR domains of ADR1-L1/L2. Removal of ADR1-L1/L2 or delivery of AvrPtoB activates SNC1, which then signals through ADR1 to trigger immunity. Our work elucidates the long-sought-after function of SNC1 in defense, and also how plants can use dual strategies, sequence diversification, and a multi-layered guard-guardee system, to counteract pathogen's attack on core immunity functions.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis Proteins/metabolism , Plant Immunity , Ubiquitination , Carrier Proteins/metabolism , Plant DiseasesABSTRACT
RATIONALE: Adult patients with Down syndrome (DS) commonly develop Hashimoto thyroiditis (HT). However, primary diffuse large B-cell lymphoma (DLBCL) of the thyroid is uncommon, and its simultaneous occurrence with HT is very rare. To our knowledge, coexisting DLBCL and HT in a patient with DS has not been reported in the medical literature. PATIENT CONCERNS: We present a 43-year-old woman with DS who reported progressive swelling of the neck on the right side and dyspnea over the previous 1 month, with associated neck ache, hoarseness, and dysphagia. Thyroid ultrasonography and computed tomography of the neck revealed a large mass in the right lobe compressing the surrounding tissues. DIAGNOSES: Based on the clinical and histopathologic findings, the patient was diagnosed with coexisting primary thyroid DLBCL and HT. INTERVENTIONS: A palliative unilateral thyroidectomy was performed; postoperative histopathology and immunohistochemistry revealed thyroid DLBCL and HT. The patient was scheduled for chemotherapy and targeted therapy after recovering from surgery. OUTCOMES: The patient died 3 weeks after surgery due to asphyxia caused by uncontrollable growth of recurrent tumor. LESSONS: The coexistence of DS, primary thyroid DLBCL, and HT is very rare. There is no standardized approach to the clinical identification of primary thyroid lymphoma (PTL), making early diagnosis difficult. A multidisciplinary approach and close follow-up are needed. The mechanisms of the link between DS and PTL are poorly understood and remain to be elucidated.