ABSTRACT
STAT6 plays a prominent role in adaptive immunity by transducing signals from extracellular cytokines. We now show that STAT6 is required for innate immune signaling in response to virus infection. Viruses or cytoplasmic nucleic acids trigger STING (also named MITA/ERIS) to recruit STAT6 to the endoplasmic reticulum, leading to STAT6 phosphorylation on Ser(407) by TBK1 and Tyr(641), independent of JAKs. Phosphorylated STAT6 then dimerizes and translocates to the nucleus to induce specific target genes responsible for immune cell homing. Virus-induced STAT6 activation is detected in all cell-types tested, in contrast to the cell-type specific role of STAT6 in cytokine signaling, and Stat6(-/-) mice are susceptible to virus infection. Thus, STAT6 mediates immune signaling in response to both cytokines at the plasma membrane, and virus infection at the endoplasmic reticulum.
Subject(s)
Immunity, Innate , Membrane Proteins/metabolism , RNA Virus Infections/immunology , RNA Viruses , STAT6 Transcription Factor/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Animals , Base Sequence , Mice , Mice, Inbred BALB C , Mice, Knockout , Molecular Sequence Data , Phosphorylation , Protein Serine-Threonine Kinases/metabolism , STAT6 Transcription Factor/geneticsABSTRACT
Renal fibrosis is a common pathway of chronic kidney disease (CKD) progression involving primary kidney injury and kidney diseases. Group 2 innate lymphoid cells (ILC2s) mediate type 2 immune responses irrespective of antigen presentation and play a reno-protective role in kidney injury and disease. In the present study, we observed a decrease in kidney-resident ILC2s in CKD and found that enrichment of ILC2s in the kidney ameliorates renal fibrosis. In CKD kidney, ILC2s preferentially produced IL-13 over IL-5 in response to IL-33 stimulation, regardless of ST2L expression. Moreover, GATA3 expression was decreased in ILC2s, and T-bet+ ILC1s and RORγt+ ILC3s were increased in CKD kidney. Adoptive transfer of kidney ILC2s into adenine-induced CKD model mouse improved renal function and fibrosis. Renal fibroblasts cultured with IL33-activated kidney ILC2s suppressed myofibroblast trans-differentiation through Acta2 and Fn-1 regulation. These results suggest that kidney ILC2s prevent CKD progression via improvement of renal fibrosis. Our findings also suggest that ILC2s may contribute to the development of new therapeutic agents and strategies for tissue fibroses.
Subject(s)
Adenine , Fibrosis , Immunity, Innate , Kidney , Lymphocytes , Mice, Inbred C57BL , Renal Insufficiency, Chronic , Animals , Renal Insufficiency, Chronic/immunology , Renal Insufficiency, Chronic/chemically induced , Mice , Lymphocytes/immunology , Lymphocytes/metabolism , Adenine/pharmacology , Adenine/analogs & derivatives , Kidney/pathology , Kidney/immunology , Male , Disease Models, Animal , Interleukin-33/metabolism , Interleukin-13/metabolismABSTRACT
BACKGROUND AND AIMS: This study aimed to determine the safety and efficacy of atezolizumab + bevacizumab therapy in hepatocellular carcinoma patients receiving anti-platelet agents or anticoagulants. METHODS: Patients were divided into those using (IM out) and those not using (IM in) anti-platelet agents or anticoagulants, who violated the exclusion criteria of the IMbrave150 trial, and were retrospectively examined. RESULTS: The study included 185 patients (IM in: 157; IM out: 28). For first-line treatment, progression-free survival was 184 days for IM in and 266 days for IM out (p = .136). Overall survival was 603 days for IM in and not reached for IM out (p = .265), with no significant between-group difference. Similarly, there were no significant between-group differences in progression-free survival or overall survival for later-line treatment. Haemorrhagic adverse events of ≥grade 3 were observed in 11 IM in patients and 3 IM out patients. No significant factors associated with haemorrhagic adverse events of ≥grade 3 were identified in the multivariate analysis including IM out classification, whose p value was .547. Regarding thrombotic/embolic adverse events in the IM out group, one case of exacerbation of portal vein thrombosis was observed. No deaths were directly attributable to bleeding events or exacerbations of thrombosis. CONCLUSION: Atezolizumab + bevacizumab therapy shows similar safety and efficacy in patients receiving and those not receiving anti-platelet agents or anticoagulants; therefore, it can be considered for patients with hepatocellular carcinoma receiving anti-platelet agents or anticoagulants.
Subject(s)
Antibodies, Monoclonal, Humanized , Anticoagulants , Bevacizumab , Carcinoma, Hepatocellular , Liver Neoplasms , Platelet Aggregation Inhibitors , Humans , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/mortality , Liver Neoplasms/drug therapy , Liver Neoplasms/mortality , Bevacizumab/therapeutic use , Bevacizumab/adverse effects , Bevacizumab/administration & dosage , Male , Female , Antibodies, Monoclonal, Humanized/therapeutic use , Antibodies, Monoclonal, Humanized/adverse effects , Retrospective Studies , Middle Aged , Aged , Platelet Aggregation Inhibitors/therapeutic use , Platelet Aggregation Inhibitors/adverse effects , Anticoagulants/therapeutic use , Anticoagulants/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Progression-Free Survival , Hemorrhage/chemically induced , AdultABSTRACT
It is a problem that influenza virus infection increases susceptibility to secondary bacterial infection in lungs leading to lethal pneumonia. We previously reported that exopolysaccharides (EPS) derived from Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 (OLL1073R-1) could prevent against influenza virus infection followed by secondary bacterial infection in vitro. Therefore, the present study assessed whether EPS derived OLL1073R-1 protects the alveolar epithelial barrier disfunction caused by influenza virus infection. After A549 cells treated with EPS or without EPS were infected influenza virus A/Puerto Rico/8/34 (IFV) for 12 h, the levels of tight junction genes expression and inflammatory genes expression were measured by reverse transcription polymerase chain reaction. As results, EPS treatment could protect against low-titer IFV infection, but not high-titer IFV infection, followed by suppression of the increased expression of inflammatory cytokine gene levels and recovery of the decrease in the expression level of ZO-1 gene that was caused by low-titer IFV infection, leading to an improvement trend in the barrier function. Our findings showed that EPS derived from OLL1073R-1 could inhibit low-titer IFV infection leading to maintenance of the epithelial barrier function through the suppression of inflammatory cytokine genes expression.
Subject(s)
Bacterial Infections , Influenza, Human , Lactobacillus delbrueckii , Orthomyxoviridae , Humans , Lactobacillus delbrueckii/genetics , Lactobacillus delbrueckii/metabolism , Tight Junctions , Cytokines/genetics , Cytokines/metabolismABSTRACT
BACKGROUND: This study aimed to examine whether the non-weight-bearing tunnel view X-ray is effective for short-term evaluation of medial meniscus posterior root tear (MMPRT) by assessing the X-ray characteristics at the initial and follow-up visits. METHODS: This was a retrospective longitudinal study of 26 enrolled knees diagnosed with MMPRT on magnetic resonance imaging. The distance between the medial tibial eminence and medial femoral condyle (MTE-MFC distance) and medial tibiofemoral joint (MTFJ) width were measured by obtaining non-weight-bearing tunnel view and frontal view X-ray radiographs. The initial and follow-up values at a median interval of 17 days were compared. Additionally, the correlations between the MTE-MFC distance increase rate and body mass index (BMI), age, femorotibial angle (FTA), and posterior tibial slope (PTS) were evaluated using linear regression analysis. RESULTS: The tunnel view images of the initial and follow-up X-rays showed a significant increase in the MTE-MFC distance and a significant decrease in the MTFJ width. Furthermore, a moderate correlation was observed between the change in the MTE-MFC distance and the time interval between X-rays. However, no substantial correlation was observed for the change in the MTFJ width over time. Moreover, no significant correlation was observed between the change in the MTE-MFC distance in the non-weight-bearing tunnel view and BMI, age, FTA, and PTS. CONCLUSIONS: The non-weight-bearing tunnel view is highly beneficial for evaluating MMPRT progression in the short term.
Subject(s)
Tibial Meniscus Injuries , Humans , Retrospective Studies , Male , Female , Middle Aged , Adult , Tibial Meniscus Injuries/diagnostic imaging , Longitudinal Studies , Radiography , Magnetic Resonance Imaging , Knee Joint/diagnostic imaging , Weight-Bearing , Follow-Up Studies , Aged , Menisci, Tibial/diagnostic imaging , Time Factors , Young AdultABSTRACT
In this study, we investigated specific and characteristic findings of the surface layer of surgical resected disc specimens in human temporomandibular joint osteoarthritis cases by transmission electron microscopy (TEM).Specimens were surgically removed from the TMJ of 5 cases (4 female patients: 5 cases) clinically osteoarthritis. Following findings were observed by TEM. Images were photographed on a JEM1400-Flash Electron microscope (JEOL, Japan) equipped with an EM-14661FLASH high-sensitivity digital complementary metal-oxide-semiconductor camera.Following findings were observed by TEM. 1) The surface is covered with plump fibroblastic and histiocytoid cells. 2) Collagen fiber bundles and collagenous matrix are exposed onto the eroded disc surface. 3) Fibrinous dense material is observed on the eroded disc surface. 4) Bundles of collagen fibers are densely observed. 5) Collagen bundles are rich around capillary vessels. 6) Synovial surface cells reveal features of activated macrophages with vacuole formation. Especially, plump fibroblastic and histiocytoid cells, and activated macrophages with vacuole, which were significant findings of the surface layer. These findings might have a significant effect on the regulation of synovial fluid.
Subject(s)
Osteoarthritis , Temporomandibular Joint Disorders , Humans , Female , Electrons , Synovial Membrane/ultrastructure , Temporomandibular Joint/surgery , Microscopy, Electron, Transmission , Collagen/ultrastructureABSTRACT
Ethanol (EtOH) effectively inactivates enveloped viruses in vitro, including influenza and severe acute respiratory syndrome coronavirus 2. Inhaled EtOH vapor may inhibit viral infection in mammalian respiratory tracts, but this has not yet been demonstrated. Here we report that unexpectedly low EtOH concentrations in solution, approximately 20% (vol/vol), rapidly inactivate influenza A virus (IAV) at mammalian body temperature and are not toxic to lung epithelial cells on apical exposure. Furthermore, brief exposure to 20% (vol/vol) EtOH decreases progeny virus production in IAV-infected cells. Using an EtOH vapor exposure system that is expected to expose murine respiratory tracts to 20% (vol/vol) EtOH solution by gas-liquid equilibrium, we demonstrate that brief EtOH vapor inhalation twice a day protects mice from lethal IAV respiratory infection by reducing viruses in the lungs without harmful side effects. Our data suggest that EtOH vapor inhalation may provide a versatile therapy against various respiratory viral infectious diseases.
Subject(s)
Influenza A virus , Influenza, Human , Mice , Animals , Humans , Influenza, Human/drug therapy , Ethanol/pharmacology , Influenza A virus/physiology , Lung , Administration, Inhalation , MammalsABSTRACT
Background and Objectives: Type V tibial tubercle avulsion fractures are extremely rare; therefore, information on them remains limited. Furthermore, although these fractures are intra-articular, to the best of our knowledge, there are no reports on their assessment via magnetic resonance imaging (MRI) or arthroscopy. Accordingly, this is the first report to describe the case of a patient undergoing detailed evaluation via MRI and arthroscopy. Case Presentation: A 13-year-old male adolescent athlete jumped while playing basketball, experienced discomfort and pain at the front of his knee, and fell down. He was transported to the emergency room by ambulance after he was unable to walk. The radiographic examination revealed a Type â ¤ tibial tubercle avulsion fracture that was displaced. In addition, an MRI scan revealed a fracture line extending to the attachment of the anterior cruciate ligament (ACL); moreover, high MRI intensity and swelling due to ACL were observed, suggesting an ACL injury. On day 4 of the injury, open reduction and internal fixation were performed. Furthermore, 4 months after surgery, bone fusion was confirmed, and metal removal was performed. Simultaneously, an MRI scan obtained at the time of injury revealed findings suggestive of ACL injury; therefore, an arthroscopy was performed. Notably, no parenchymal ACL injury was observed, and the meniscus was intact. The patient returned to sports 6 months postoperatively. Conclusion: Type V tibial tubercle avulsion fractures are known to be extremely rare. Based on our report, we suggest that MRI should be performed without hesitation if intra-articular injury is suspected.
Subject(s)
Anterior Cruciate Ligament Injuries , Fractures, Avulsion , Tibial Fractures , Male , Adolescent , Humans , Anterior Cruciate Ligament Injuries/complications , Anterior Cruciate Ligament Injuries/diagnostic imaging , Anterior Cruciate Ligament Injuries/surgery , Fractures, Avulsion/diagnostic imaging , Fractures, Avulsion/etiology , Fractures, Avulsion/surgery , Tibial Fractures/diagnostic imaging , Tibial Fractures/etiology , Tibial Fractures/surgery , Tibia/diagnostic imaging , Anterior Cruciate LigamentABSTRACT
Stromules are dynamic membrane-bound tubular structures that emanate from plastids. Stromule formation is triggered in response to various stresses and during plant development, suggesting that stromules may have physiological and developmental roles in these processes. Despite the possible biological importance of stromules and their prevalence in green plants, their exact roles and formation mechanisms remain unclear. To explore these issues, we obtained Arabidopsis thaliana mutants with excess stromule formation in the leaf epidermis by microscopy-based screening. Here, we characterized one of these mutants, stromule biogenesis altered 1 (suba1). suba1 forms plastids with severely altered morphology in a variety of non-mesophyll tissues, such as leaf epidermis, hypocotyl epidermis, floral tissues, and pollen grains, but apparently normal leaf mesophyll chloroplasts. The suba1 mutation causes impaired chloroplast pigmentation and altered chloroplast ultrastructure in stomatal guard cells, as well as the aberrant accumulation of lipid droplets and their autophagic engulfment by the vacuole. The causal defective gene in suba1 is TRIGALACTOSYLDIACYLGLYCEROL5 (TGD5), which encodes a protein putatively involved in the endoplasmic reticulum (ER)-to-plastid lipid trafficking required for the ER pathway of thylakoid lipid assembly. These findings suggest that a non-mesophyll-specific mechanism maintains plastid morphology. The distinct mechanisms maintaining plastid morphology in mesophyll versus non-mesophyll plastids might be attributable, at least in part, to the differential contributions of the plastidial and ER pathways of lipid metabolism between mesophyll and non-mesophyll plastids.
Subject(s)
Arabidopsis Proteins/physiology , Arabidopsis/cytology , Carrier Proteins/physiology , Mesophyll Cells/physiology , Plastids/physiology , Arabidopsis/growth & development , Chloroplasts/ultrastructure , Flowers/cytology , Mesophyll Cells/ultrastructure , Mutation , Plant Epidermis/cytology , Plant Epidermis/genetics , Plant Leaves/cytology , Plant Leaves/genetics , Plant Roots/cytology , Plant Stomata , Plants, Genetically Modified , Plastids/ultrastructureABSTRACT
Renal fibrosis is a common pathway in the progression of various kidney diseases and injuries. Unilateral ureteral obstruction (UUO) induces renal fibrosis, and immune responses profoundly affect its pathogenesis. Group2 innate lymphoid cells (ILC2s) are strongly activated by interleukin (IL) -33, which is a member of IL-1 family and recognize as alarmin. ILC2s quickly produce large amounts of type 2 cytokines including IL-5 and IL-13, which are involved in inflammation, tissue homeostasis, and wound healing. However, the relationship between renal fibrosis and ILC2s has been unclear. In the present study, we investigated the roles of the ILC2/L-33 axis in renal fibrosis using a UUO model. We found that kidney ILC2s decreased in UUO-affected kidneys compared with their counterpart kidneys despite IL-33 upregulation. There was no effect of reactive oxygen species or TGF-ß from reduced ILC2 caused by UUO. Pretreatment with IL-33 before UUO induced ILC2s and Tregs in kidneys and alleviated renal fibrosis. Furthermore, this protective effect was maintained even when CD4+T cells was depleted. These findings demonstrated that ILC2s play a predominant role in the suppressive function of renal fibrosis mediated by pretreatment with IL-33. In contrast, post-treatment with IL-33 after UUO increased ILC2s in kidneys but had no therapeutic effect on renal fibrosis. Our findings suggest that ILC2s have potential roles in the prevention of renal fibrosis and can serve as a therapeutic and diagnostic target.
Subject(s)
Kidney Diseases , Ureteral Obstruction , Fibrosis , Humans , Immunity, Innate , Interleukin-33/metabolism , Kidney/metabolism , Kidney Diseases/metabolism , Lymphocytes/metabolism , Ureteral Obstruction/metabolismABSTRACT
We developed a chiral symmetry breaking method for monoacylated meso diols. The X-ray crystal structure analysis of monoacylated 1,4-anhydroerythritols, meso cyclic diols with a cis configuration, revealed that the O-(p-anisoyl) derivative crystallized as a racemic conglomerate of the P21 21 21 crystal system. It was confirmed that the substrate racemized by intramolecular transfer of the acyl group in the presence of a catalytic amount of base. Evaporating the solvent gradually from the solution or Viedma ripening to promote crystallization-induced deracemization efficiently led to enantiomer crystals. These results provide the first successful example of asymmetric expression and amplification by deracemization of sugar derivatives without an external chemical chiral source. Furthermore, we applied this methodology to acyclic meso-1,2-diols. Three O-monoacylated substrates were successfully deracemized to 99 % ee by Viedma ripening. We also developed asymmetric desymmetrization of meso-1,2-diols by combining acylation and crystallization-induced deracemization.
Subject(s)
Alcohols , Acylation , Alcohols/chemistry , Catalysis , Crystallization , StereoisomerismABSTRACT
A multiprotein complex, THO/TREX, couples the transcription, 3'-end formation and nuclear export of mRNAs. In this study, we report that crucial factors for mRNA processing, such as XRN2, DDX5/DDX17 and CstF64, are copurified with human THO (hTHO). Using chromatin immunoprecipitation, we found increased cross-linking of XRN2 and CstF64 to the RNA polymerase II (RNAP II) pause site of the HSPA1A gene upon down-regulation of THOC5, a metazoan-specific component of hTHO. As observed in THOC5-depleted cells, knockdown of XRN2 blocked HSP70 transcript release and increased the amount of CstF64 at the pause site. In addition, our data indicate that DDX5/DDX17 is also required for HSP70 transcript release. As the degradation of read-through transcripts, but not cleavage at polyadenylation sites per se, was hindered upon THOC5 or DDX5/DDX17 down-regulation, these factors appear to influence transcriptional termination. Interestingly, over-expression of RNase H suppressed the accumulation of HSP70 transcripts in nuclear foci in THOC5- or DDX5/DDX17-depleted cells. Thus, we propose a model in which hTHO, along with DDX5/DDX17, restricts the formation of R-loops, thereby facilitating the XRN2-mediated transcriptional termination and release of the mature transcript from the HSPA1A locus.
Subject(s)
HSP70 Heat-Shock Proteins/genetics , Nuclear Proteins/metabolism , RNA, Messenger/genetics , Transcription Termination, Genetic , DEAD-box RNA Helicases/metabolism , Exoribonucleases/metabolism , HSP70 Heat-Shock Proteins/metabolism , HeLa Cells , Humans , Protein Binding , RNA Polymerase II/metabolism , RNA, Messenger/metabolismABSTRACT
The aim of this study is to reveal the morphological property about the loose bodies (LBs) of temporomandibular joint (TMJ) by scanning electron microscope (SEM). We obtained specimens from two female cases of released loose body by surgical operation. These specimens were fixed by soaking in a mixture of 5% glutaraldehyde or 4% formaldehyde for one week. They were cut into half pieces. These specimens were observed at an accelerating voltage of 3 kV under a SEM (JSM-5500, JEOL, Tokyo). In the electron microscopic findings, it seems to be separated into two different parts as inside part and outside part. On the inside part, collagen fibers were running very densely in the same direction in an orderly neatly manner. Whereas, we observed waved collagen fibers running irregularly with many spaces on the outside part. Outside part seems to be porous pattern compared with inside part. It might be that the surface and outside part included many active fibroblasts. As results, it seems that the LBs might develop in a multi-layer style, in which fibrous tissues were piled up loosely around the inside part. The proliferating activity of LBs grows from the inside to outside of SC in TMJ.
Subject(s)
Chondromatosis, Synovial/pathology , Joint Loose Bodies/pathology , Temporomandibular Joint/ultrastructure , Chondromatosis, Synovial/etiology , Chondromatosis, Synovial/surgery , Collagen/ultrastructure , Female , Fibroblasts/pathology , Fibroblasts/ultrastructure , Humans , Joint Loose Bodies/complications , Joint Loose Bodies/surgery , Microscopy, Electron, Scanning , Temporomandibular Joint/pathology , Temporomandibular Joint/surgeryABSTRACT
Dynamic enantioselective crystallization enabled the chiral symmetry breaking of two spiropyrans and one spirooxazine. The three spiro compounds afforded racemic conglomerate crystals, and easily racemized in alcoholic solution without irradiation. Optically pure enantiomorphic crystals were obtained by vapor-diffusion crystallization or attrition-enhanced deracemization (Viedma ripening). Their absolute configurations were determined by single-crystal X-ray analysis and each enantiomorphic crystal was correlated with its solid-state circular dichroism (CD) spectrum.
ABSTRACT
The purpose of this study is to determine whether or not trehangelin A (THG-A) is effective in treating the metabolic clinical condition caused by a high-fat diet. The body weight, epididymal adipose volume, alanine transaminase (ALT), total-cholesterol (T-CHO), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and glucose concentrations in serum increased in mice fed a high-fat diet compared to mice fed a control diet. On the other hand, adiponectin level in serum of mice fed a high-fat diet decreased compared to that of control mice. When mice fed a high-fat diet were intraperitoneally administered THG-A of 20 mg/kg three times per week, the levels of TG and glucose in serum were significantly reduced compared to those fed high-fat without THG-A. Interestingly, the levels of high-density lipoprotein cholesterol (HDL-C) in serum were increased by THG-A administration in both mice fed a control diet and those fed high-fat diet. The decreased level of adiponectin by a high-fat diet was also recovered by THG-A treatment. The liver expression of mRNA from pro-inflammatory cytokines, including interleukin (IL)-6 and tumor necrosis factor (TNF)-α, were significantly increased in mice fed a high-fat diet compared to those fed a control diet. However, the increased IL-6 levels in mice fed a high-fat diet were significantly suppressed by THG-A treatment. Furthermore, the increased expression of TNF-α mRNA or COL1A2 mRNA by a high-fat diets tended to be decreased in mice treated with THG-A. These results show that THG-A treatment attenuates the progression of metabolic clinical conditions, suggesting its potential efficacy against obesity-related metabolic disorders.
Subject(s)
Diet, High-Fat , Trehalose/analogs & derivatives , Adiponectin/blood , Animals , Blood Glucose/drug effects , Collagen Type I/genetics , Collagen Type I, alpha 1 Chain , Insulin/blood , Interleukin-1beta/genetics , Interleukin-6/genetics , Liver/drug effects , Liver/metabolism , Liver/pathology , Liver Cirrhosis/drug therapy , Liver Cirrhosis/genetics , Male , Mice, Inbred C57BL , RNA, Messenger/metabolism , Trehalose/pharmacology , Trehalose/therapeutic use , Triglycerides/blood , Tumor Necrosis Factor-alpha/geneticsABSTRACT
Photodimerization of 3-arylindenones in solution and in the solid state was examined. Irradiation of 3-arylindenones in benzene exclusively gave C2-symmetric anti-HH cyclobutane dimers in good yields. In contrast, photolysis in the solid state afforded syn-HH cyclobutane dimers efficiently, which was considerably influenced by the molecular arrangement in the crystal lattice.
ABSTRACT
Asymmetric Diels-Alder reaction was achieved under achiral conditions. Reaction of prochiral 2-methylfuran and N-phenylmaleimide in heptane or hexane solution at 80 °C efficiently gave a conglomerate crystal of exo-type Diels-Alder adduct selectively, and continuous suspension of the reaction mixture with glass beads promoted attrition-enhanced deracemization, leading to an optically active exo-adduct in 90% ee.
ABSTRACT
Stromules, or stroma-filled tubules, are thin extensions of the plastid envelope membrane that are most frequently observed in undifferentiated or non-mesophyll cells. The formation of stromules is developmentally regulated and responsive to biotic and abiotic stress; however, the physiological roles and molecular mechanisms of the stromule formation remain enigmatic. Accordingly, we attempted to obtain Arabidopsis thaliana mutants with aberrant stromule biogenesis in the leaf epidermis. Here, we characterize one of the obtained mutants. Plastids in the leaf epidermis of this mutant were giant and pleomorphic, typically having one or more constrictions that indicated arrested plastid division, and usually possessed one or more extremely long stromules, which indicated the deregulation of stromule formation. Genetic mapping, whole-genome resequencing-aided exome analysis, and gene complementation identified PARC6/CDP1/ARC6H, which encodes a vascular plant-specific, chloroplast division site-positioning factor, as the causal gene for the stromule phenotype. Yeast two-hybrid assay and double mutant analysis also identified a possible interaction between PARC6 and MinD1, another known chloroplast division site-positioning factor, during the morphogenesis of leaf epidermal plastids. To the best of our knowledge, PARC6 is the only known A. thaliana chloroplast division factor whose mutations more extensively affect the morphology of plastids in non-mesophyll tissue than in mesophyll tissue. Therefore, the present study demonstrates that PARC6 plays a pivotal role in the morphology maintenance and stromule regulation of non-mesophyll plastids.
Subject(s)
Arabidopsis/metabolism , Epidermis/metabolism , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Mutation , Plant Leaves/genetics , Plant Leaves/metabolism , Plastids/genetics , Plastids/metabolismABSTRACT
A novel regioselective cyclization reaction of N-cinnamoylthioureas leading to six- or five-membered heterocyclic compounds was developed. N-Cinnamoylthioureas in the presence of trifluoroacetic acid (TFA) underwent the well-established intramolecular cycloaddition reaction to give 2-imino-2,3,5,6-tetrahydro-4H-1,3-thiazin-4-ones in good yields. On the other hand, the reaction with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) proceeded in an unprecedented "umpolung" cyclization fashion to afford five-membered 2-imino-1,3-thiazolidin-4-ones and/or 2-thioxoimidazolidine-4-ones. The reaction was considered to occur via a cycloadduct of DBU with the cinnamoyl moiety followed by intramolecular attack of the thiourea group.
ABSTRACT
Porcine placental extract (PPE) is used as a nonprescription drug for analeptics and in health foods and cosmetics in Japan, Korea and China. It was reported that PPE has anti-oxidative and anti-inflammatory activities; however, the mechanisms and the responsible molecules involved in these activities are still unclear. Here, we investigated how enzymatically prepared PPE affects proinflammatory factors such as interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α in a cultured macrophage cell line, RAW264.7, when co-stimulated with lipopolysaccharide (LPS). Enhanced production of IL-1ß, IL-6 and TNF-α by LPS was significantly reduced by the addition of PPE and these effects were dose dependent. Nitric oxide (NO) production induced in cultured macrophages by LPS was also inhibited by PPE. Real-time PCR after the reverse transcription of total RNAs isolated from cells treated with PPE revealed that the mRNA expressions of IL-1ß, IL-6, TNFα, and NO synthase (NOS)-2 were reduced. The necessary concentration of PPE prepared by enzymatic digestion to mediate anti-inflammatory effects compared with the reported value of that extracted by phosphate buffered saline without digestion was proportional to the amount of extracted materials from the same amount of placenta (about 10-fold). This suggests that the molecules responsible for the anti-inflammatory activity exists in the placenta and can be extracted by phosphate buffered saline, and thus might survive enzymatic digestion.