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1.
Nature ; 599(7885): 471-476, 2021 11.
Article in English | MEDLINE | ID: mdl-34732892

ABSTRACT

Small, soluble metabolites not only are essential intermediates in intracellular biochemical processes, but can also influence neighbouring cells when released into the extracellular milieu1-3. Here we identify the metabolite and neurotransmitter GABA as a candidate signalling molecule synthesized and secreted by activated B cells and plasma cells. We show that B cell-derived GABA promotes monocyte differentiation into anti-inflammatory macrophages that secrete interleukin-10 and inhibit CD8+ T cell killer function. In mice, B cell deficiency or B cell-specific inactivation of the GABA-generating enzyme GAD67 enhances anti-tumour responses. Our study reveals that, in addition to cytokines and membrane proteins, small metabolites derived from B-lineage cells have immunoregulatory functions, which may be pharmaceutical targets allowing fine-tuning of immune responses.


Subject(s)
B-Lymphocytes/metabolism , Interleukin-10/immunology , Macrophages/metabolism , Neoplasms/immunology , gamma-Aminobutyric Acid/metabolism , Animals , B-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Cell Proliferation , Female , Gene Deletion , Glutamate Decarboxylase/deficiency , Glutamate Decarboxylase/genetics , Humans , Inflammation/immunology , Inflammation/prevention & control , Macrophages/immunology , Male , Mice , Neoplasms/pathology , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism , gamma-Aminobutyric Acid/biosynthesis
2.
Plant Cell ; 35(12): 4347-4365, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-37713604

ABSTRACT

The extended tubular shape of root hairs is established by tip growth and concomitant hardening. Here, we demonstrate that a syntaxin of plants (SYP)123-vesicle-associated membrane protein (VAMP)727-dependent secretion system delivers secondary cell wall components for hardening the subapical zone and shank of Arabidopsis (Arabidopsis thaliana) root hairs. We found increased SYP123 localization at the plasma membrane (PM) of the subapical and shank zones compared with the tip region in elongating root hairs. Inhibition of phosphatidylinositol (PtdIns)(3,5)P2 production impaired SYP123 localization at the PM and SYP123-mediated root hair shank hardening. Moreover, root hair elongation in the syp123 mutant was insensitive to a PtdIns(3,5)P2 synthesis inhibitor. SYP123 interacts with both VAMP721 and VAMP727. syp123 and vamp727 mutants exhibited reduced shank cell wall stiffness due to impaired secondary cell wall component deposition. Based on these results, we conclude that SYP123 is involved in VAMP721-mediated conventional secretion for root hair elongation as well as in VAMP727-mediated secretory functions for the delivery of secondary cell wall components to maintain root hair tubular morphology.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cytoplasm/metabolism , Cell Wall/metabolism , Phosphatidylinositols/metabolism , SNARE Proteins/genetics , SNARE Proteins/metabolism , Plant Roots , R-SNARE Proteins/genetics , R-SNARE Proteins/metabolism
3.
J Allergy Clin Immunol ; 148(2): 563-573.e7, 2021 08.
Article in English | MEDLINE | ID: mdl-33581199

ABSTRACT

BACKGROUND: The programmed cell death-1 (PD-1)/programmed death ligand 1 (PD-L1) pathway is known to inhibit the activation of effector CD8+ T cells. However, just how this regulatory pathway is involved in the pathophysiology of CD8+ T-cell-mediated inflammatory skin diseases remains unclear. OBJECTIVE: Our aim was to elucidate the mechanisms by which the PD-1/PD-L1 pathway exerts its regulatory roles in CD8+ T-cell-mediated cutaneous immune responses. METHODS: PD-L1-deficient (Pdl1-/-) mice were used for the murine contact hypersensitivity model. Inflammatory responses such as IFN-γ production from CD8+ T cells in the skin was evaluated by flow cytometry. RESULTS: Compared with wild-type mice, Pdl1-/- mice exhibited exacerbated ear swelling and increased numbers of IFN-γ+ CD8+ T cells in the skin. Adoptive T-cell transfer experiments revealed the involvement of the PD-1/PD-L1 pathway in the elicitation phase of contact hypersensitivity. Bone marrow chimera experiments showed that PD-L1 on radioresistant cells was responsible for this regulatory pathway. Flow cytometric analysis revealed that among the radioresistant cells in the skin, PD-L1 was most highly expressed on mast cells (MCs) before and after elicitation. Administration of anti-PD-L1 blocking antibody during the elicitation phase significantly enhanced ear swelling responses and increased the number of IFN-γ+CD8+ T cells in the skin of wild-type mice, whereas no significant effects were observed in MC-deficient (WBB6F1/J-KitW/KitW-v/J and C57BL/6-KitW-sh/W-sh) mice. The high level of expression of PD-L1 on human skin MCs was confirmed by database analysis and immunohistochemical analysis. CONCLUSION: PD-L1 on MCs negatively regulates CD8+ T-cell activation in the skin.


Subject(s)
B7-H1 Antigen/immunology , CD8-Positive T-Lymphocytes/immunology , Dermatitis, Contact/immunology , Lymphocyte Activation , Skin/immunology , Animals , B7-H1 Antigen/genetics , CD8-Positive T-Lymphocytes/pathology , Dermatitis, Contact/genetics , Dermatitis, Contact/pathology , Mice , Mice, Knockout , Programmed Cell Death 1 Receptor/genetics , Programmed Cell Death 1 Receptor/immunology , Skin/pathology
4.
Plant Physiol ; 182(4): 2199-2212, 2020 04.
Article in English | MEDLINE | ID: mdl-32024698

ABSTRACT

Despite the importance of preventing calcium (Ca) deficiency disorders in agriculture, knowledge of the molecular mechanisms underlying plant adaptations to low-Ca conditions is limited. In this study, we provide evidence for a crucial involvement of callose synthesis in the survival of Arabidopsis (Arabidopsis thaliana) under low-Ca conditions. A mutant sensitive to low-Ca conditions, low calcium sensitive3 (lcs3), exhibited high levels of cell death in emerging leaves and had defects in its expanding true leaves under low-Ca conditions. Further analyses showed that the causal mutation was located in a putative ß-1,3-glucan (callose) synthase gene, GLUCAN SYNTHASE-LIKE10 (GSL10). Yeast complementation assay results showed that GSL10 encodes a functional callose synthase. Ectopic callose significantly accumulated in wild-type plants under low-Ca conditions, but at a low level in lcs3 The low-Ca sensitivity of lcs3 was phenocopied by the application of callose synthase inhibitors in wild-type plants, which resulted in leaf expansion failure, cell death, and reduced ectopic callose levels under low-Ca conditions. Transcriptome analyses showed that the expression of genes related to cell wall and defense responses was altered in both wild-type plants under low-Ca conditions and in lcs3 under normal-Ca conditions, suggesting that GSL10 is required for the alleviation of both cell wall damage and defense responses caused by low Ca levels. These results suggest that callose synthesis is essential for the prevention of cell death under low-Ca conditions and plays a key role in plants' survival strategies under low-Ca conditions.


Subject(s)
Arabidopsis/metabolism , Calcium/metabolism , Glucans/metabolism , Plant Leaves/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Gene Expression Regulation, Plant/genetics , Gene Expression Regulation, Plant/physiology , Glucosyltransferases/genetics , Glucosyltransferases/metabolism
5.
Int J Mol Sci ; 22(17)2021 Aug 30.
Article in English | MEDLINE | ID: mdl-34502330

ABSTRACT

Galls are characteristic plant structures formed by cell size enlargement and/or cell proliferation induced by parasitic or pathogenic organisms. Insects are a major inducer of galls, and insect galls can occur on plant leaves, stems, floral buds, flowers, fruits, or roots. Many of these exhibit unique shapes, providing shelter and nutrients to insects. To form unique gall structures, gall-inducing insects are believed to secrete certain effector molecules and hijack host developmental programs. However, the molecular mechanisms of insect gall induction and development remain largely unknown due to the difficulties associated with the study of non-model plants in the wild. Recent advances in next-generation sequencing have allowed us to determine the biological processes in non-model organisms, including gall-inducing insects and their host plants. In this review, we first summarize the adaptive significance of galls for insects and plants. Thereafter, we summarize recent progress regarding the molecular aspects of insect gall formation.


Subject(s)
Host-Parasite Interactions , Insecta/physiology , Plant Tumors/etiology , Plants/parasitology , Animals
6.
Langmuir ; 36(36): 10846-10852, 2020 Sep 15.
Article in English | MEDLINE | ID: mdl-32881532

ABSTRACT

Recently, smaller-size electron-beam (EB) accelerators have offered EB irradiation in laboratory systems. Therefore, polymer surface treatments with low-energy EB have been developed in the past years. For high adhesion strength, low-energy EB treatment is also a promising method in comparison to plasma surface treatment. In the plasma treatment, the mechanism of the effect on the adhesion properties has been proved and the excess treatments led to the formation of a weak boundary layer and reduction of adhesion strength. In contrast, the low-energy EB possesses high penetration ability. In this work, we focused on the surface treatments of isotactic polypropylene (it.PP) with low-energy EB irradiation for adhesion. The dependence of adhesion strength on the absorbed dose of electron beam was evaluated, and the mechanism of electron beam on the adhesion properties was investigated from various perspectives of surface properties and morphology. Compared to that of plasma-treated it.PP, the adhesion strength of it.PP with electron-beam irradiation increased drastically. We proved that the radical was generated in the substrates after electron-beam treatments and would form covalent bonds between adhesives and substrates, which achieved higher adhesion than plasma treatments. In addition, the electron beam reached effectively a deep region from the top surface of the substrates and provided larger adhesion strength.

7.
Plant Physiol ; 177(4): 1529-1538, 2018 08.
Article in English | MEDLINE | ID: mdl-29884680

ABSTRACT

Pollen viability depends on dynamic vacuolar changes during pollen development involving increases and decreases of vacuolar volume through water and osmolite accumulation and vacuolar fission. Mutations in FAB1A to FAB1D, the genes encoding phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2]-converting kinases, are male gametophyte lethal in Arabidopsis (Arabidopsis thaliana) due to defective vacuolar fission after pollen mitosis I, suggesting a key role of the phospholipid in dynamic vacuolar organization. However, other genetic components that regulate the production of PI(3,5)P2 and its involvement in pollen germination and tube growth are unknown. Here, we identified and characterized Arabidopsis VAC14, a homolog of the yeast and metazoan VAC14s that are crucial for the production of PI(3,5)P2VAC14 is constitutively expressed and highly present in developing pollen. Loss of function of VAC14 was male gametophyte lethal due to defective pollen development. Ultrastructural studies showed that vacuolar fission after pollen mitosis I was compromised in vac14 mutant microspores, which led to pollen abortion. We further showed that inhibiting the production of PI(3,5)P2 or exogenous application of PI(3,5)P2 mimicked or rescued the pollen developmental defect of the vac14 mutant, respectively. Genetic interference and pharmacological approaches suggested a role of PI(3,5)P2 in pollen germination and tube growth. Our results provide insights into the function of VAC14 and, by inference, that of PI(3,5)P2 in plant cells.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/growth & development , Pollen/growth & development , Vacuoles/metabolism , Aminopyridines/pharmacology , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Flowers/genetics , Gene Expression Regulation, Plant , Heterocyclic Compounds, 3-Ring/pharmacology , Membrane Proteins/chemistry , Mutation , Phosphatidylinositol Phosphates/metabolism , Plants, Genetically Modified , Pollen/cytology , Pollen/drug effects , Saccharomyces cerevisiae Proteins/chemistry , Sequence Homology, Amino Acid , Vacuoles/genetics
8.
Adv Exp Med Biol ; 1111: 139-157, 2019.
Article in English | MEDLINE | ID: mdl-30499079

ABSTRACT

The integrity of cellular membranes is maintained not only by structural phospholipids such as phosphatidylcholine and phosphatidylethanolamine, but also by regulatory phospholipids, phosphatidylinositol phosphates (phosphoinositides). Although phosphoinositides constitute minor membrane phospholipids, they exert a wide variety of regulatory functions in all eukaryotic cells. They act as key markers of membrane surfaces that determine the biological integrity of cellular compartments to recruit various phosphoinositide-binding proteins. This review focuses on recent progress on the significance of phosphoinositides, their modifying enzymes, and phosphoinositide-binding proteins in Arabidopsis.


Subject(s)
Arabidopsis/enzymology , Arabidopsis/metabolism , Phosphatidylinositols/chemistry , Phosphatidylinositols/metabolism , Arabidopsis/cytology , Cell Membrane/chemistry , Cell Membrane/metabolism , Phosphatidylinositol Phosphates/chemistry , Phosphatidylinositol Phosphates/metabolism
9.
Plant Cell Physiol ; 58(1): 120-129, 2017 01 01.
Article in English | MEDLINE | ID: mdl-27803131

ABSTRACT

Phosphoinositides play an important role in various membrane trafficking events in eukaryotes. One of them, however, phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2], has not been studied widely in plants. Using a combination of fluorescent reporter proteins and the PI(3,5)P2-specific inhibitor YM202636, here we demonstrated that in Arabidopsis thaliana, PI(3,5)P2 affects various membrane trafficking events, mostly in the post-Golgi routes. We found that YM201636 treatment effectively reduced PI(3,5)P2 concentration not only in the wild type but also in FAB1A-overexpressing Arabidopsis plants. In particular, reduced PI(3,5)P2 levels caused abnormal membrane dynamics of plasma membrane proteins, AUX1 and BOR1, with different trafficking patterns. Secretion and morphological characteristics of late endosomes and vacuoles were also affected by the decreased PI(3,5)P2 production. These pleiotropic defects in the post-Golgi trafficking events were caused by the inhibition of PI(3,5)P2 production. This effect is probably mediated by the inhibition of maturation of FAB1-positive late endosomes, thereby impairing late endosome function. In conclusion, our results imply that in Arabidopsis, late endosomes are involved in multiple post-Golgi membrane trafficking routes including not only vacuolar trafficking and endocytosis but also secretion.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/metabolism , Cell Membrane/metabolism , Membrane Transport Proteins/metabolism , Phosphatidylinositol Phosphates/metabolism , Aminopyridines/pharmacology , Antiporters/genetics , Antiporters/metabolism , Arabidopsis/drug effects , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Endosomes/drug effects , Endosomes/metabolism , Gene Expression Regulation, Plant/drug effects , Genetic Pleiotropy/genetics , Golgi Apparatus/drug effects , Golgi Apparatus/metabolism , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Heterocyclic Compounds, 3-Ring/pharmacology , Membrane Transport Proteins/genetics , Microscopy, Confocal , Mutation , Phosphatidylinositol Phosphates/antagonists & inhibitors , Phosphotransferases (Alcohol Group Acceptor)/genetics , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Plant Roots/drug effects , Plant Roots/genetics , Plant Roots/metabolism , Plants, Genetically Modified , Protein Transport/drug effects , Protein Transport/genetics , Reverse Transcriptase Polymerase Chain Reaction , Vacuoles/drug effects , Vacuoles/metabolism
10.
Plant Cell Physiol ; 58(7): 1185-1195, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28158631

ABSTRACT

Phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] is a low-abundance phospholipid known to be associated with a wide variety of physiological functions in plants. However, the localization and dynamics of PI(3,5)P2 in plant cells remain largely unknown, partially due to the lack of an effective fluorescent probe. Using Arabidopsis transgenic plant expressing the PI(3,5)P2-labeling fluorescent probe (tagRFP-ML1N*2) developed based on a tandem repeat of the cytosolic phosphoinositide-interacting domain (ML1N) of the mammalian lysosomal transient receptor potential cation channel, Mucolipin 1 (TRPML1), here we show that PI(3,5)P2 is predominantly localized on the limited membranes of the FAB1- and SNX1-positive late endosomes, but rarely localized on the membranes of plant vacuoles or trans-Golgi network/early endosomes of cortical cells of the root differentiation zone. The late endosomal localization of tagRFP-ML1N*2 is reduced or abolished by pharmacological inhibition or genetic knockdown of expression of genes encoding PI(3,5)P2-synthesizing enzymes, FAB1A/B, but markedly increased with FAB1A overexpression. Notably, reactive oxygen species (ROS) significantly increase late endosomal levels of PI(3,5)P2. Thus, tandem ML1N-based PI(3,5)P2 probes can reliably monitor intracellular dynamics of PI(3,5)P2 in Arabidopsis cells with less binding activity to other endomembrane organelles.


Subject(s)
Arabidopsis/metabolism , Fluorescent Dyes/metabolism , Phosphatidylinositol Phosphates/metabolism , Arabidopsis/cytology , Arabidopsis/genetics , Endosomes/metabolism , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Lysosomes/metabolism , Microscopy, Confocal , Phosphatidylinositols/analysis , Plant Roots/cytology , Plant Roots/genetics , Plant Roots/metabolism , Plants, Genetically Modified , Reactive Oxygen Species/metabolism , Recombinant Fusion Proteins , Transport Vesicles/metabolism , Vacuoles/metabolism , trans-Golgi Network/metabolism , Red Fluorescent Protein
11.
Plant Physiol ; 169(3): 1961-74, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26353760

ABSTRACT

Phosphatidylinositol 3,5-bisphosphate [PtdIns(3,5)P2] is an important lipid in membrane trafficking in animal and yeast systems; however, its role is still largely obscure in plants. Here, we demonstrate that the phosphatidylinositol 3-phosphate 5-kinase, formation of aploid and binucleate cells1 (FAB1)/FYVE finger-containing phosphoinositide kinase (PIKfyve), and its product, PtdIns(3,5)P2, are essential for the maturation process of endosomes to mediate cortical microtubule association of endosomes, thereby controlling proper PIN-FORMED protein trafficking in young cortical and stele cells of root. We found that FAB1 predominantly localizes on the Sorting Nexin1 (SNX1)-residing late endosomes, and a loss of FAB1 function causes the release of late endosomal proteins, Ara7, and SNX1 from the endosome membrane, indicating that FAB1, or its product PtdIns(3,5)P2, mediates the maturation process of the late endosomes. We also found that loss of FAB1 function causes the release of endosomes from cortical microtubules and disturbs proper cortical microtubule organization.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/enzymology , Endosomes/metabolism , Gene Expression Regulation, Plant , Microtubules/metabolism , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Arabidopsis/cytology , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Gene Expression Regulation, Enzymologic , Genes, Reporter , Indoleacetic Acids/metabolism , Intracellular Membranes/metabolism , Models, Biological , Mutation , Phosphates/metabolism , Phosphatidylinositol 3-Kinase/genetics , Phosphatidylinositol 3-Kinase/metabolism , Phosphatidylinositol Phosphates/metabolism , Phosphotransferases (Alcohol Group Acceptor)/genetics , Protein Transport , Sorting Nexins/genetics , Sorting Nexins/metabolism , rab GTP-Binding Proteins/genetics , rab GTP-Binding Proteins/metabolism
12.
Plant Cell Physiol ; 55(4): 790-800, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24642714

ABSTRACT

Root hairs are fast-growing tubular protrusions on root epidermal cells that play important roles in water and nutrient uptake in plants. The tip-focused polarized growth of root hairs is accomplished by the secretion of newly synthesized materials to the tip via the polarized membrane trafficking mechanism. Here, we report the function of two different types of plasma membrane (PM) Qa-SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors), SYP123 and SYP132, in the growth of root hair in Arabidopsis. We found that SYP123, but not SYP132, localizes in the tip region of root hairs by recycling between the brefeldin A (BFA)-sensitive endosomes and the PM of the expanding tip in an F-actin-dependent manner. The vesicle-associated membrane proteins VAMP721/722/724 also exhibited tip-focused localization in root hairs and formed ternary SNARE complexes with both SYP123 and SYP132. These results demonstrate that SYP123 and SYP132 act in a coordinated fashion to mediate tip-focused membrane trafficking for root hair tip growth.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/growth & development , Arabidopsis/metabolism , Plant Roots/growth & development , Qa-SNARE Proteins/metabolism , Actins/metabolism , Arabidopsis/drug effects , Brefeldin A/pharmacology , Bridged Bicyclo Compounds, Heterocyclic/pharmacology , Fluorescence Recovery After Photobleaching , Green Fluorescent Proteins/metabolism , Models, Biological , Multiprotein Complexes/metabolism , Mutation/genetics , Phenotype , Plant Roots/cytology , Plant Roots/drug effects , Protein Binding/drug effects , Protein Transport/drug effects , Recombinant Fusion Proteins/metabolism , SNARE Proteins/metabolism , Thiazolidines/pharmacology
13.
Palliat Care Soc Pract ; 18: 26323524231222497, 2024.
Article in English | MEDLINE | ID: mdl-38188459

ABSTRACT

Background: Culturally appropriate communication training programs for a wide range of professions that can be used during infection epidemics are crucial for advance care planning implementation. Starting in 2018, the Japanese Ministry of Health, Labour and Welfare made a major policy change, and doctors, nurses, and social workers, and care managers were identified in the guidelines as the professions that promote advance care planning. Motivated by the lack of online programs for Japanese care managers, we proposed a new one-day program. Objectives: This study aimed to determine the changes in the positive attitude of care managers toward dying patients compared to that of nurses, which has been used in past literature as an outcome of advance care planning educational interventions, after administering the program in Japan. Design: Before-after comparison study. Methods: Care managers were recruited through our website, ACP-Piece, http://plaza.umin.ac.jp/~acp-piece/piece.html. A questionnaire survey concerning positive attitudes toward dying patients was administered before and after the program on 28 August 2021. Sixty-six subjects participated in the training and 60 participants, including 14 care managers, consented to the study and completed the questionnaire surveys before and after the program. Results: The Frommelt attitude toward care of the dying scores for care managers increased after the program (p-values, confidence intervals, and effect sizes: p < 0.001, -11.90 to -4.388, -1.252). After training, care managers had a significantly higher maximum score occurrence than nurses. Older care managers with advance care planning experience may have had a higher maximum score occurrence compared to younger, inexperienced participants. Conclusion: To our knowledge, this is the first to demonstrate the increased positive attitude scores toward dying patients after online communication training for Japanese care managers. The limitations of this study include the lack of evidence regarding reasons for score changes, long-term score changes, and effectiveness for patients and their families.

14.
J Clin Invest ; 134(7)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38557498

ABSTRACT

BACKGROUNDPrecise stratification of patients with non-small cell lung cancer (NSCLC) is needed for appropriate application of PD-1/PD-L1 blockade therapy.METHODSWe measured soluble forms of the immune-checkpoint molecules PD-L1, PD-1, and CTLA-4 in plasma of patients with advanced NSCLC before PD-1/PD-L1 blockade. A prospective biomarker-finding trial (cohort A) included 50 previously treated patients who received nivolumab. A retrospective observational study was performed for patients treated with any PD-1/PD-L1 blockade therapy (cohorts B and C), cytotoxic chemotherapy (cohort D), or targeted therapy (cohort E). Plasma samples from all patients were assayed for soluble immune-checkpoint molecules with a highly sensitive chemiluminescence-based assay.RESULTSNonresponsiveness to PD-1/PD-L1 blockade therapy was associated with higher concentrations of these soluble immune factors among patients with immune-reactive (hot) tumors. Such an association was not apparent for patients treated with cytotoxic chemotherapy or targeted therapy. Integrative analysis of tumor size, PD-L1 expression in tumor tissue (tPD-L1), and gene expression in tumor tissue and peripheral CD8+ T cells revealed that high concentrations of the 3 soluble immune factors were associated with hyper or terminal exhaustion of antitumor immunity. The combination of soluble PD-L1 (sPD-L1) and sCTLA-4 efficiently discriminated responsiveness to PD-1/PD-L1 blockade among patients with immune-reactive tumors.CONCLUSIONCombinations of soluble immune factors might be able to identify patients unlikely to respond to PD-1/PD-L1 blockade as a result of terminal exhaustion of antitumor immunity. Our data suggest that such a combination better predicts, along with tPD-L1, for the response of patients with NSCLC.TRIAL REGISTRATIONUMIN000019674.FUNDINGThis study was funded by Ono Pharmaceutical Co. Ltd. and Sysmex Corporation.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Immune Checkpoint Inhibitors , Lung Neoplasms , Humans , B7-H1 Antigen , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Immunologic Factors/blood , Immunologic Factors/chemistry , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Programmed Cell Death 1 Receptor , Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use
15.
Sci Rep ; 13(1): 2554, 2023 02 13.
Article in English | MEDLINE | ID: mdl-36781988

ABSTRACT

Insect galls are abnormal plant organs formed by gall-inducing insects to provide shelter and nutrients for themselves. Although insect galls are spatialized complex structures with unique shapes and functions, the molecular mechanism of the gall formation and the screening system for the gall inducing effectors remains unknown. Here, we demonstrate that an extract of a gall-inducing aphid, Schlechtendalia chinensis, induces an abnormal structure in the root-tip region of Arabidopsis seedlings. The abnormal structure is composed of stem-like cells, vascular, and protective tissues, as observed in typical insect galls. Furthermore, we confirm similarities in the gene expression profiles between the aphid-treated seedlings and the early developmental stages of Rhus javanica galls formed by S. chinensis. Based on the results, we propose a model system for analyzing the molecular mechanisms of gall formation: the Arabidopsis-based Gall-Forming Assay (Ab-GALFA). Ab-GALFA could be used not only as a model to elucidate the mechanisms underlying gall formation, but also as a bioassay system to isolate insect effector molecules of gall-induction.


Subject(s)
Aphids , Arabidopsis , Animals , Arabidopsis/genetics , Insecta/genetics , Aphids/genetics , Transcriptome , Plant Tumors/genetics
16.
J Biol Chem ; 286(7): 5803-12, 2011 Feb 18.
Article in English | MEDLINE | ID: mdl-21148564

ABSTRACT

Chondroitin sulfate (CS) is a glycosaminoglycan, consisting of repeating disaccharide units of N-acetylgalactosamine and glucuronic acid residues, and plays important roles in development and homeostasis of organs and tissues. Here, we generated and analyzed mice lacking chondroitin sulfate N-acetylgalactosaminyltransferase 1 (CSGalNAcT-1). Csgalnact1(-/-) mice were viable and fertile but exhibited slight dwarfism. Biochemically, the level of CS in Csgalnact1(-/-) cartilage was reduced to ∼50% that of wild-type cartilage, whereas its chain length was similar to wild-type mice, indicating that CSGalNAcT-1 participates in the CS chain initiation as suggested in the previous study (Sakai, K., Kimata, K., Sato, T., Gotoh, M., Narimatsu, H., Shinomiya, K., and Watanabe, H. (2007) J. Biol. Chem. 282, 4152-4161). Histologically, the growth plate of Csgalnact1(-/-) mice contained shorter and slightly disorganized chondrocyte columns with a reduced volume of the extracellular matrix principally in the proliferative layer. Immunohistochemical analysis revealed that the level of both aggrecan and link protein 1 were decreased in Csgalnact1(-/-) cartilage. Western blot analysis demonstrated an increase in processed forms of aggrecan core protein. These results suggest that CSGalNAcT-1 is required for normal levels of CS biosynthesis in cartilage. Our observations suggest that CSGalNAcT-1 is necessary for normal levels of endochondral ossification, and the decrease in CS amount in the growth plate by its absence causes a rapid catabolism of aggrecan.


Subject(s)
Aggrecans/metabolism , Cartilage/enzymology , Chondrocytes/enzymology , Chondroitin Sulfates/biosynthesis , Growth Plate/enzymology , N-Acetylgalactosaminyltransferases/metabolism , Osteogenesis/physiology , Aggrecans/genetics , Animals , Cartilage/metabolism , Chondrocytes/cytology , Chondroitin Sulfates/genetics , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Growth Plate/cytology , Mice , Mice, Knockout , N-Acetylgalactosaminyltransferases/genetics , Proteoglycans/genetics , Proteoglycans/metabolism
17.
Plant Physiol ; 155(2): 797-807, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21173023

ABSTRACT

In eukaryotic cells, PtdIns 3,5-kinase, Fab1/PIKfyve produces PtdIns (3,5) P(2) from PtdIns 3-P, and functions in vacuole/lysosome homeostasis. Herein, we show that expression of Arabidopsis (Arabidopsis thaliana) FAB1A/B in fission yeast (Schizosaccharomyces pombe) fab1 knockout cells fully complements the vacuole morphology phenotype. Subcellular localizations of FAB1A and FAB1B fused with green fluorescent protein revealed that FAB1A/B-green fluorescent proteins localize to the endosomes in root epidermal cells of Arabidopsis. Furthermore, reduction in the expression levels of FAB1A/B by RNA interference impairs vacuolar acidification and endocytosis. These results indicate that Arabidopsis FAB1A/B functions as PtdIns 3,5-kinase in plants and in fission yeast. Conditional knockdown mutant shows various phenotypes including root growth inhibition, hyposensitivity to exogenous auxin, and disturbance of root gravitropism. These phenotypes are observed also in the overproducing mutants of FAB1A and FAB1B. The overproducing mutants reveal additional morphological phenotypes including dwarfism, male-gametophyte sterility, and abnormal floral organs. Taken together, this evidence indicates that imbalanced expression of FAB1A/B impairs endomembrane homeostasis including endocytosis, vacuole formation, and vacuolar acidification, which causes pleiotropic developmental phenotypes mostly related to the auxin signaling in Arabidopsis.


Subject(s)
Arabidopsis Proteins/genetics , Arabidopsis/cytology , Cell Membrane/physiology , Endosomes/physiology , Phosphotransferases (Alcohol Group Acceptor)/genetics , Arabidopsis/enzymology , Arabidopsis/genetics , Gene Knockdown Techniques , Genetic Complementation Test , Gravitropism , Homeostasis , Indoleacetic Acids/pharmacology , Mutation , Plant Infertility , Plant Roots/growth & development , Plants, Genetically Modified/cytology , Plants, Genetically Modified/enzymology , Plants, Genetically Modified/genetics , RNA, Plant/genetics , Schizosaccharomyces/genetics , Schizosaccharomyces/metabolism , Vacuoles/metabolism
18.
Sci Transl Med ; 14(675): eabq0021, 2022 12 14.
Article in English | MEDLINE | ID: mdl-36516270

ABSTRACT

Despite the success of cancer immunotherapies such as programmed cell death-1 (PD-1) and PD-1 ligand 1 (PD-L1) inhibitors, patients often develop resistance. New combination therapies with PD-1/PD-L1 inhibitors are needed to overcome this issue. Bezafibrate, a ligand of peroxisome proliferator-activated receptor-γ coactivator 1α/peroxisome proliferator-activated receptor complexes, has shown a synergistic antitumor effect with PD-1 blockade in mice that is mediated by activation of mitochondria in T cells. We have therefore now performed a phase 1 trial (UMIN000017854) of bezafibrate with nivolumab in previously treated patients with advanced non-small cell lung cancer. The primary end point was the percentage of patients who experience dose-limiting toxicity, and this combination regimen was found to be well tolerated. Preplanned comprehensive analysis of plasma metabolites and gene expression in peripheral cytotoxic T cells indicated that bezafibrate promoted T cell function through up-regulation of mitochondrial metabolism including fatty acid oxidation and may thereby have prolonged the duration of response. This combination strategy targeting T cell metabolism thus has the potential to maintain antitumor activity of immune checkpoint inhibitors and warrants further validation.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Mice , Animals , Nivolumab/therapeutic use , Programmed Cell Death 1 Receptor , Bezafibrate/therapeutic use , Peroxisome Proliferator-Activated Receptors/therapeutic use , Ligands , B7-H1 Antigen
19.
Plant Signal Behav ; 15(11): 1802553, 2020 11 01.
Article in English | MEDLINE | ID: mdl-32752971

ABSTRACT

Acute and chronic arsenic (As) toxicity is a global health issue affecting millions of people, which leads to inactivation of over 200 enzymes, particularly those involved in cellular energy pathways and DNA synthesis and repair. The fern Pteris vittata acts as a hyperaccumulator of As and may be useful for phytoremediation to reduce disposal risks by utilizing metal-enriched plant biomass in energy and metal recovery. However, these ferns grow in limited environments and its transplantation and transport can be challenging. Therefore, we generated a transgenic Arabidopsis plant as a seed plant model, capable of accumulating As in their vacuole lumen. This was achieved by transforming the As-resistant bacterial As transporter, ArsB, via fusion with a organelle-targeting signal to the vacuolar membrane, N-ethyl-maleimide-sensitive factor attachment protein receptors (SNAREs) protein, VAMP711. In this study, we developed the iVenus assay as a method for detecting whether the N- or C-terminus of a membrane protein is located on the cytoplasmic or exoplasmic side, and from the result of the iVenus assay, we generated the transgenic plant introduced N-terminal end of ArsB with VAMP711, localized to the central vacuolar membrane to accumulate As in the shoot and differentiation zone of root.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/metabolism , Arsenic/metabolism , Biodegradation, Environmental , SNARE Proteins/metabolism , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Roots/genetics , Plant Roots/metabolism , Plant Shoots/genetics , Plant Shoots/metabolism , Pteris/genetics , Pteris/metabolism , SNARE Proteins/genetics , Vacuoles/metabolism
20.
Front Plant Sci ; 11: 471, 2020.
Article in English | MEDLINE | ID: mdl-32499792

ABSTRACT

Insect galls are unique organs that provide shelter and nutrients to the gall-inducing insects. Although insect galls are fascinating structures for their unique shapes and functions, the process by which gall-inducing insects induce such complex structures is not well understood. Here, we performed RNA-sequencing-based comparative transcriptomic analysis of the early developmental stage of horned gall to elucidate the early gall-inducing process carried out by the aphid, Schlechtendalia chinensis, in the Chinese sumac, Rhus javanica. There was no clear similarity in the global gene expression profiles between the gall tissue and other tissues, and the expression profiles of various biological categories such as phytohormone metabolism and signaling, stress-response pathways, secondary metabolic pathways, photosynthetic reaction, and floral organ development were dramatically altered. Particularly, master transcription factors that regulate meristem, flower, and fruit development, and biotic and abiotic stress-responsive genes were highly upregulated, whereas the expression of genes related to photosynthesis strongly decreased in the early stage of the gall development. In addition, we found that the expression of class-1 KNOX genes, whose ectopic overexpression is known to lead to the formation of de novo meristematic structures in leaf, was increased in the early development stage of gall tissue. These results strengthen the hypothesis that gall-inducing insects convert source tissues into fruit-like sink tissues by regulating the gene expression of host plants and demonstrate that such manipulation begins from the initial process of gall induction.

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