31 research outputs found
Enzymatic control of anhydrobiosis-related accumulation of trehalose in the sleeping chironomid, Polypedilum vanderplanki
Larvae of an anhydrobiotic insect, Polypedilum vanderplanki, accumulate very large amounts of trehalose as a compatible solute on desiccation, but the molecular mechanisms underlying this accumulation are unclear. We therefore isolated the genes coding for trehalose metabolism enzymes, i.e. trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) for the synthesis step, and trehalase (TREH) for the degradation step. Although computational prediction indicated that the alternative splicing variants (PvTpsα/β) obtained encoded probable functional motifs consisting of a typical consensus domain of TPS and a conserved sequence of TPP, PvTpsα did not exert activity as TPP, but only as TPS. Instead, a distinct gene (PvTpp) obtained expressed TPP activity. Previous reports have suggested that insect TPS is, exceptionally, a bifunctional enzyme governing both TPS and TPP. In this article, we propose that TPS and TPP activities in insects can be attributed to discrete genes. The translated product of the TREH ortholog (PvTreh) certainly degraded trehalose to glucose. Trehalose was synthesized abundantly, consistent with increased activities of TPS and TPP and suppressed TREH activity. These results show that trehalose accumulation observed during anhydrobiosis induction in desiccating larvae can be attributed to the activation of the trehalose synthetic pathway and to the depression of trehalose hydrolysis
MMMDB: Mouse Multiple Tissue Metabolome Database
The Mouse Multiple Tissue Metabolome Database (MMMDB) provides comprehensive and quantitative metabolomic information for multiple tissues from single mice. Manually curated databases that integrate literature-based individual metabolite information have been available so far. However, data sets on the absolute concentration of a single metabolite integrated from multiple resources are often difficult to be used when different metabolomic studies are compared because the relative balance of the multiple metabolite concentrations in the metabolic pathways as a snapshot of a dynamic system is more important than the absolute concentration of a single metabolite. We developed MMMDB by performing non-targeted analyses of cerebra, cerebella, thymus, spleen, lung, liver, kidney, heart, pancreas, testis and plasma using capillary electrophoresis time-of-flight mass spectrometry and detected 428 non-redundant features from which 219 metabolites were successfully identified. Quantified concentrations of the individual metabolites and the corresponding processed raw data; for example, the electropherograms and mass spectra with their annotations, such as isotope and fragment information, are stored in the database. MMMDB is designed to normalize users’ data, which can be submitted online and used to visualize overlaid electropherograms. Thus, MMMDB allows newly measured data to be compared with the other data in the database. MMMDB is available at: http://mmmdb.iab.keio.ac.jp
A novel three-unit tRNA splicing endonuclease found in ultrasmall Archaea possesses broad substrate specificity
tRNA splicing endonucleases, essential enzymes found in Archaea and Eukaryotes, are involved in the processing of pre-tRNA molecules. In Archaea, three types of splicing endonuclease [homotetrameric: α4, homodimeric: α2, and heterotetrameric: (αβ)2] have been identified, each representing different substrate specificity during the tRNA intron cleavage. Here, we discovered a fourth type of archaeal tRNA splicing endonuclease (ε2) in the genome of the acidophilic archaeon Candidatus Micrarchaeum acidiphilum, referred to as ARMAN-2 and its closely related species, ARMAN-1. The enzyme consists of two duplicated catalytic units and one structural unit encoded on a single gene, representing a novel three-unit architecture. Homodimeric formation was confirmed by cross-linking assay, and site-directed mutagenesis determined that the conserved L10-pocket interaction between catalytic and structural unit is necessary for the assembly. A tRNA splicing assay reveal that ε2 endonuclease cleaves both canonical and non-canonical bulge–helix–bulge motifs, similar to that of (αβ)2 endonuclease. Unlike other ARMAN and Euryarchaeota, tRNAs found in ARMAN-2 are highly disrupted by introns at various positions, which again resemble the properties of archaeal species with (αβ)2 endonuclease. Thus, the discovery of ε2 endonuclease in an archaeon deeply branched within Euryarchaeota represents a new example of the coevolution of tRNA and their processing enzymes
Brown adipose tissue dysfunction promotes heart failure via a trimethylamine N-oxide-dependent mechanism.
Low body temperature predicts a poor outcome in patients with heart failure, but the underlying pathological mechanisms and implications are largely unknown. Brown adipose tissue (BAT) was initially characterised as a thermogenic organ, and recent studies have suggested it plays a crucial role in maintaining systemic metabolic health. While these reports suggest a potential link between BAT and heart failure, the potential role of BAT dysfunction in heart failure has not been investigated. Here, we demonstrate that alteration of BAT function contributes to development of heart failure through disorientation in choline metabolism. Thoracic aortic constriction (TAC) or myocardial infarction (MI) reduced the thermogenic capacity of BAT in mice, leading to significant reduction of body temperature with cold exposure. BAT became hypoxic with TAC or MI, and hypoxic stress induced apoptosis of brown adipocytes. Enhancement of BAT function improved thermogenesis and cardiac function in TAC mice. Conversely, systolic function was impaired in a mouse model of genetic BAT dysfunction, in association with a low survival rate after TAC. Metabolomic analysis showed that reduced BAT thermogenesis was associated with elevation of plasma trimethylamine N-oxide (TMAO) levels. Administration of TMAO to mice led to significant reduction of phosphocreatine and ATP levels in cardiac tissue via suppression of mitochondrial complex IV activity. Genetic or pharmacological inhibition of flavin-containing monooxygenase reduced the plasma TMAO level in mice, and improved cardiac dysfunction in animals with left ventricular pressure overload. In patients with dilated cardiomyopathy, body temperature was low along with elevation of plasma choline and TMAO levels. These results suggest that maintenance of BAT homeostasis and reducing TMAO production could be potential next-generation therapies for heart failure.We thank Kaori Yoshida, Keiko Uchiyama, Satomi Kawai, Naomi Hatanaka, Yoko Sawaguchi, Runa Washio,
Takako Ichihashi, Nanako Koike, Keiko Uchiyama, Masaaki Nameta (Niigata University), Kaori Igarashi, Kaori
Saitoh, Keiko Endo, Hiroko Maki, Ayano Ueno, Maki Ohishi, Sanae Yamanaka, Noriko Kagata (Keio University)
for their excellent technical assistance, C. Ronald Kahn (Joslin Diabetes Center and Harvard Medical School)
for providing the BAT cell line, Evan Rosen (Harvard Medical School) for providing us Ucp-Cre mice, Kosuke
Morikawa (Kyoto University), Tomitake Tsukihara (University of Hyogo) and Shinya Yoshikawa (University of
Hyogo) for their professional opinions and suggestions. Tis work was supported by a Grant-in-Aid for Scientifc Research (A) (20H00533) from MEXT, AMED under Grant Numbers JP20ek0210114, and AMED-CREST
under Grant Number JP20gm1110012, and Moonshot Research and Development Program (21zf0127003s0201),
MEXT Supported Program for the Strategic Research Foundation at Private Universities Japan, Private University
Research Branding Project, and Leading Initiative for Excellent Young Researchers, and grants from the Takeda
Medical Research Foundation, the Vehicle Racing Commemorative Foundation, Ono Medical Research Foundation, and the Suzuken Memorial Foundation (to T.M.). Support was also provided by a Grants-in-Aid for Young
Scientists (Start-up) (26893080), and grants from the Uehara Memorial Foundation, Kowa Life Science Foundation, Manpei Suzuki Diabetes Foundation, SENSHIN Medical Research Foundation, ONO Medical Research
Foundation, Tsukada Grant for Niigata University Medical Research, Te Nakajima Foundation, SUZUKEN
memorial foundation, HOKUTO Corporation, Mochida Memorial Foundation for Medical & Pharmaceutical
Research, Grants-in-Aid for Encouragement of Young Scientists (A) (16H06244), Daiichi Sankyo Foundation of
Life Science, AMED Project for Elucidating and Controlling Mechanisms of Aging and Longevity under Grant
Number JP17gm5010002, JP18gm5010002, JP19gm5010002, JP20gm5010002, JP21gm5010002, Astellas Foundation for Research on Metabolic Disorders, Research grant from Naito Foundation, Te Japan Geriatrics Society
(to I.S.); by a Grant-in-Aid for Scientifc Research (C) (19K08974), Yujin Memorial Grant, Sakakibara Memorial
Research Grant from Te Japan Research Promotion Society for Cardiovascular Diseases, TERUMO Life Science Foundation, Kanae Foundation (to Y.Y.), JST ERATO (JPMJER1902), AMED-CREST (JP20gm1010009),
the Takeda Science Foundation, the Food Science Institute Foundation (to S.F.), and by a grant from Bourbon
(to T.M., I.S. and Y.Y.).S
WNT7A regulation by miR-15b in ovarian cancer
WNT signaling is well known to play an important role in the regulation of development, cell proliferation and cell differentiation in a wide variety of normal and cancerous tissues. Despite the wealth of knowledge concerning when and where various WNT genes are expressed and downstream events under their control, there is surprisingly little published evidence of how they are regulated. We have recently reported that aberrant WNT7A is observed in serous ovarian carcinomas, and WNT7A is the sole ligand accelerating ovarian tumor progression through CTNNB1 (β-catenin)/TCF signaling in the absence of CTNNB1 mutations. In the present study, we report that WNT7A is a direct target of miR-15b in ovarian cancer. We showed that a luciferase reporter containing the putative binding site of miR-15b in the WNT7A 3'-UTR was significantly repressed by miR-15b. Mutation of the putative binding site of miR-15b in the WNT7A 3'-UTR restored luciferase activity. Furthermore, miR-15b was able to repress increased levels of TOPFLASH activity by WNT7A, but not those induced by S33Y. Additionally, miR-15b dose-dependently decreased WNT7A expression. When we evaluated the prognostic impact of WNT7A and miR-15b expression using TCGA datasets, a significant inverse correlation in which high-expression of WNT7A and low-expression of miR-15b was associated with reduced survival rates of ovarian cancer patients. Treatment with decitabine dose-dependently increased miR-15b expression, and silencing of DNMT1 significantly increased miR-15b expression. These results suggest that WNT7A is post-transcriptionally regulated by miR-15b, which could be down-regulated by promoter hypermethylation, potentially via DNMT1, in ovarian cancer
Construction Technological Project of Outbuildings it manufacturing facility in Kromeriz
The thesis contains the main part of the building and technological project of outbuildings it manufacturing facility. There is prepared a technical report on the structural and technological project, situation with broder relations roadways, time and financial plan, studies the implementation of major technological stages, project construction site, design of building machines and mechanisms, plan for securing materiál resources, technological regulation for warm flat roof and saddle truss roof, inspection and test plans, budget and health and safety at the technological stage roofed
Estimation of change in pleural pressure in assisted and unassisted spontaneous breathing pediatric patients using fluctuation of central venous pressure: A preliminary study.
BackgroundIt is important to evaluate the size of respiratory effort to prevent patient self-inflicted lung injury and ventilator-induced diaphragmatic dysfunction. Esophageal pressure (Pes) measurement is the gold standard for estimating respiratory effort, but it is complicated by technical issues. We previously reported that a change in pleural pressure (ΔPpl) could be estimated without measuring Pes using change in CVP (ΔCVP) that has been adjusted with a simple correction among mechanically ventilated, paralyzed pediatric patients. This study aimed to determine whether our method can be used to estimate ΔPpl in assisted and unassisted spontaneous breathing patients during mechanical ventilation.MethodsThe study included hemodynamically stable children (aged ResultsOf the 14 patients enrolled in the study, 6 were excluded because correct positioning of the esophageal balloon could not be confirmed, leaving eight patients for analysis (mean age, 4.8 months). Three variables that reflected ΔPpl (ΔPes, ΔCVP, and cΔCVP-derived ΔPpl) were measured and yielded the following results: -6.7 ± 4.8, - -2.6 ± 1.4, and - -7.3 ± 4.5 cmH2O, respectively. The repeated measures correlation between cΔCVP-derived ΔPpl and ΔPes showed that cΔCVP-derived ΔPpl had good correlation with ΔPes (r = 0.84, pConclusionsΔPpl can be estimated reasonably accurately by ΔCVP using our method in assisted and unassisted spontaneous breathing children during mechanical ventilation