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1.
Physiol Genomics ; 55(12): 647-653, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37694281

ABSTRACT

The aim of the present study was to investigate changes in the gut microbiome both during and after consumption of malted rice amazake (MR-Amazake), a fermented food from Japan, in-home healthcare patients with disabilities, including patients with severe motor and intellectual disabilities. We monitored 12 patients who consumed MR-Amazake for 6 wk and investigated them before and after the intervention as well as 6 wk after the end of intake to compare their physical condition, diet, type of their medication, constipation assessment scale, and analysis of their comprehensive fecal microbiome using 16S rRNA sequencing. Their constipation symptoms were significantly alleviated, and principal coordinate analysis revealed that 30% of patients showed significant changes in the gut microbiome after MR-Amazake ingestion. Furthermore, Bifidobacterium was strongly associated with these changes. These changes were observed only during MR-Amazake intake; the original gut microbiome was restored when MR-Amazake intake was discontinued. These results suggest that 6 wk is a reasonable period of time for MR-Amazake to change the human gut microbiome and that continuous consumption of MR-Amazake is required to sustain such changes.NEW & NOTEWORTHY The consumption of malted rice amazake (MR-Amazake) showed significant changes in the gut microbiome according to principal coordinate analysis in some home healthcare patients with disabilities, including those with severe motor and intellectual disabilities. After discontinuation of intake, the gut microbiome returned to its original state. This is the first pilot study to examine both the changes in the gut microbiome and their sustainability after MR-Amazake intake.


Subject(s)
Disabled Persons , Gastrointestinal Microbiome , Intellectual Disability , Oryza , Humans , Gastrointestinal Microbiome/genetics , Oryza/genetics , Pilot Projects , RNA, Ribosomal, 16S/genetics , Feces/microbiology , Constipation/microbiology , Delivery of Health Care
2.
Des Monomers Polym ; 26(1): 190-197, 2023.
Article in English | MEDLINE | ID: mdl-37426066

ABSTRACT

The donor-acceptor type π-conjugated polymers having heterole units were prepared by the reaction of a regioregular organometallic polymer having both reactive titanacyclopentadiene and electron-donor thiophene-2,5-diyl units in the main chain with electrophiles such as diphenyltin dichloride, dichlorophenylphosphine, and diiodophenylarsine. For example, a polymer having electron-accepting phosphole unit was obtained in 54% yield whose number-average molecular weight (Mn) and molecular weight distribution (Mw/Mn) were estimated as 3,000 and 1.9, respectively. The obtained polymer exhibits a high highest occupied molecular orbital (HOMO) and low lowest unoccupied molecular orbital (LUMO) energy levels (-5.13 eV and -3.25 eV, respectively) due to the electron-donating thiophene and electron-accepting phosphole units. Reflecting upon the alternating structure of thiophene and phosphole, the polymer exhibits a band gap energy level (Eg) of 1.78 eV which is narrower than that of a derivative of poly(thiophene) (Eg = 2.25 eV).

3.
Nutrients ; 13(12)2021 Dec 14.
Article in English | MEDLINE | ID: mdl-34960021

ABSTRACT

Constipation is a frequent complication in patients with severe motor and intellectual disabilities (SMID). The aim of this study was to investigate changes in constipation symptoms and gut microbiota associated with the intake of malted rice amazake, a fermented food in Japan, in patients with SMID. Ten patients consumed the test food for six weeks, and their physical condition, dietary and medication status, and constipation assessment scale (CAS) were investigated. Comprehensive fecal microbiome analysis using the 16S rRNA sequence method was performed. The results showed a significant decrease in CAS, and a significant increase in Lactobacillales and decrease in Escherichia-Shigella after consuming malted rice amazake. To investigate the difference in the effects of malted rice amazake consumption, based on the characteristics of the original gut microbiota, the patients were grouped according to the similarity of their gut microbiota before the intervention; Firmicutes-rich Group 1 (n = 5), Actinobacteria-rich Group 2 (n = 4), and Proteobacteria-rich Group 3 (n = 1). The CAS decreased in Groups 1 and 2. The relative abundance of Bifidobacterium showed an increasing tendency both overall and in Group 1, but it was originally higher in Group 2. Our results suggest that malted rice amazake consumption reduces constipation symptoms and simultaneously changes the gut microbiota, but the changes may vary depending on the original composition of the gut microbiota.


Subject(s)
Constipation/diet therapy , Disabled Persons , Gastrointestinal Microbiome/drug effects , Intellectual Disability , Oryza , Seedlings , Adult , Bacteria/drug effects , Bacteria/genetics , Child , Feces/microbiology , Female , Humans , Male , Pilot Projects , RNA, Bacterial , RNA, Ribosomal, 16S
4.
Placenta ; 103: 53-58, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33075721

ABSTRACT

INTRODUCTION: To date, details on how iron is supplied from the mother to the fetus through the placenta have remained unclear. Recently, increasing evidence has shown that heme oxygenase (HO)-1, which is an inducible isoform of the rate-limiting enzyme in the heme degradation pathway, may be involved in the effective reutilization of iron. In this study, we examined the distribution and gene expression of HO-1 in the villous tissue of human placenta at various periods of pregnancy. METHODS: Using the placenta of 38 samples for which consent was obtained, chronological changes in the localization of HO-1 protein were examined by histological examination. RT-PCR was also performed to examine the expression of HO-1, transferrin receptor-1, and ferroportin 1. Ferric iron in the tissues was analyzed by Prussian blue staining. RESULTS: Immunohistochemical studies showed that HO-1 protein was exclusively expressed in trophoblastic cells throughout gestation. In the miscarriage placenta in the first trimester, ho-1 mRNA levels were significantly higher than normal. Placenta with fetal death (miscarriage) in the first and second trimester indicate significantly higher ratio of ho-1 gene for iron production to the fpn-1 gene for iron excretion than normal. These suggest that the role of HO-1 with various physiological functions is changing throughout pregnancy. DISCUSSION: These findings suggest that HO-1 in placenta plays an important role in iron supplying system in the second trimester to support fetal development.


Subject(s)
Fetus/metabolism , Heme Oxygenase-1/physiology , Iron/metabolism , Placenta/metabolism , Abortion, Induced , Abortion, Spontaneous/genetics , Abortion, Spontaneous/metabolism , Abortion, Spontaneous/pathology , Adult , Female , Fetal Death/etiology , Heme Oxygenase-1/genetics , Humans , Iron/supply & distribution , Maternal-Fetal Exchange/physiology , Metabolic Networks and Pathways/genetics , Placental Circulation/physiology , Pregnancy , Pregnancy Trimester, First/metabolism , Pregnancy Trimester, Second/metabolism , Pregnancy Trimester, Third/metabolism , Trophoblasts/metabolism , Trophoblasts/pathology
5.
Angew Chem Int Ed Engl ; 55(48): 15040-15043, 2016 11 21.
Article in English | MEDLINE | ID: mdl-27860176

ABSTRACT

A synthetic method to obtain an arsole-containing π-conjugated polymer by the post-transformation of the organotitanium polymer titanacyclopentadiene-2,5-diyl unit with an arsenic-containing building block is described. The UV/Vis absorption maximum and onset of the polymer were observed at 517 nm and 612 nm, respectively. The polymer exhibits orange photoluminescence with an emission maximum (Emax ) of 600 nm and the quantum yield (Φ) of 0.05. The polymer proved to exhibit a quasi-reversible redox behavior in its cyclic voltammetric (CV) analysis. The energy levels of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) were estimated to be -5.43 and -3.24 eV, respectively, from the onsets for oxidation and reduction signals in the CV analysis. Further chemical modification of the arsole unit in the π-conjugated polymer by complexation of gold(I) chloride occurred smoothly resulting in the bathochromic shift of the UV/Vis absorption and lowering of the LUMO energy level.

6.
Org Lett ; 17(19): 4854-7, 2015 Oct 02.
Article in English | MEDLINE | ID: mdl-26359577

ABSTRACT

2,5-Diarylarsoles were easily synthesized from nonvolatile arsenic precursors. Diiodoarsine was generated in situ and reacted with titanacyclopentadienes to give 2,5-diarylarsoles. The structures and optical properties were studied in comparison with those of 2,5-diarylphosphole. It was found that the arsoles were much more stable in the air than the phosphole. Single crystal X-ray diffraction revealed the arsenic atoms adopted a trigonal pyramidal structure, reflecting on the s-character of the lone pair. The obtained 2,5-diarylarsoles and 2,5-diarylphosphole showed intense emission in solutions and solid state. In addition, the optical properties were controlled by transition-metal coordination.

7.
Clin Exp Pharmacol Physiol ; 41(1): 89-97, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24117876

ABSTRACT

1. Transgenic (TG) mice overexpressing an arg120gly missense mutation in heat shock protein B5 (HSPB5; i.e. R120G TG mice) exhibit desmin-related cardiomyopathy. Recently, the cardioprotective effect of nicorandil has been shown to prolong the survival of R120G TG mice. However, whether the TG mice exhibit ventricular arrhythmias and whether nicorandil can inhibit these arrhythmias remain unknown. In the present study we examined the effects of chronic nicorandil administration on ventricular electrical remodelling and arrhythmias in R120G TG mice. 2. Mice were administered nicorandil (15 mg/kg per day) or vehicle (water) orally from 5 to 30 weeks of age. Electrocardiograms (ECG) and optical action potentials were recorded from R120G TG mouse hearts. In addition, the expression of ventricular connexin 43 and the cardiac Na(+) channel Nav1.5 was examined in TG mice. 3. All ECG parameters tested were prolonged in R120G TG compared with non-transgenic (NTG) mice. Nicorandil improved the prolonged P, PQ and QRS intervals in R120G TG mice. Interestingly, impulse conduction slowing and increases in the expression of total and phosphorylated connexin 43 and Nav1.5 were observed in ventricles from R120G TG compared with NTG mice. Nicorandil improved ventricular impulse conduction slowing and normalized the increased protein expression levels of total and phosphorylated connexin 43, but not of Nav1.5, in R120G TG mouse hearts. Electrical rapid pacing at the ventricle induced ventricular tachyarrhythmias (VT) in six of eight R120G TG mouse hearts, but not in any of the eight nicorandil-treated R120G TG mouse hearts (P < 0.05). 4. These findings demonstrate that nicorandil inhibits cardiac electrical remodelling and that the prevention of VT by nicorandil is associated with normalization of connexin 43 expression in this model.


Subject(s)
Anti-Arrhythmia Agents/pharmacology , Cardiomyopathies/physiopathology , Desmin/physiology , Nicorandil/pharmacology , Tachycardia, Ventricular/prevention & control , Anesthesia , Animals , Blotting, Western , Body Weight/drug effects , Connexin 43/biosynthesis , Echocardiography , Electric Stimulation , Electrocardiography , Electrophysiological Phenomena/drug effects , Immunohistochemistry , In Vitro Techniques , Mice , Mice, Transgenic , NAV1.5 Voltage-Gated Sodium Channel/biosynthesis , Organ Size/drug effects
8.
Biochem Biophys Res Commun ; 430(1): 320-4, 2013 Jan 04.
Article in English | MEDLINE | ID: mdl-23159623

ABSTRACT

We previously characterized RNA polymerase II-associated protein 3 (RPAP3) as a cell death enhancer. Here we report the identification and characterization of splicing isoform of RPAP3, isoform 1 and 2. We investigated the interaction between RPAP3 and PIH1 domain containing protein 1 (PIH1D1), and found that RPAP3 isoform 1, but not isoform 2, interacted with PIH1D1. Furthermore, knockdown of RPAP3 isoform 1 by small interfering RNA down-regulated PIH1D1 protein level without affecting PIH1D1 mRNA. RPAP3 isoform 2 potentiated doxorubicin-induced cell death in human breast cancer T-47 cells although isoform 1 showed no effect. These results suggest that R2TP complex is composed of RPAP3 isoform 1 for its stabilization, and that RPAP3 isoform 2 may have a dominant negative effect on the survival potency of R2TP complex.


Subject(s)
Apoptosis Regulatory Proteins/metabolism , Carrier Proteins/metabolism , Amino Acid Sequence , Carrier Proteins/genetics , Cell Line, Tumor , Cell Survival , Down-Regulation , Doxorubicin/pharmacology , Gene Knockdown Techniques , HEK293 Cells , Humans , Molecular Sequence Data , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Messenger/metabolism , RNA, Small Interfering/genetics , Signal Transduction , TOR Serine-Threonine Kinases/metabolism
9.
Cell Tissue Res ; 345(2): 231-41, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21789578

ABSTRACT

We examined the toxicity of methamphetamine and dopamine in CATH.a cells, which were derived from mouse dopamine-producing neural cells in the central nervous system. Use of the quantitative real-time polymerase chain reaction revealed that transcripts of the endoplasmic reticulum stress related gene (CHOP/Gadd153/ddit3) were considerably induced at 24-48 h after methamphetamine administration (but only under apoptotic conditions), whereas dopamine slightly induced CHOP/Gadd153/ddit3 transcripts at an early stage. We also found that dopamine and methamphetamine weakly induced transcripts for the glucose-regulated protein 78 gene (Grp78/Bip) at the early stage. Analysis by immunofluorescence microscopy demonstrated an increase of CHOP/Gadd153/ddit3 and Grp78/Bip proteins at 24 h after methamphetamine administration. Treatment of CATH.a cells with methamphetamine caused a re-distribution of dopamine inside the cells, which mimicked the presynaptic activity of neurons with cell bodies located in the ventral tegmental area or the substantia nigra. Thus, we have demonstrated the existence of endoplasmic reticulum stress in a model of presynaptic dopaminergic neurons for the first time. Together with the recent evidence suggesting the importance of presynaptic toxicity, our findings provide new insights into the mechanisms of dopamine toxicity, which might represent one of the most important mechanisms of methamphetamine toxicity and addiction.


Subject(s)
Endoplasmic Reticulum/drug effects , Methamphetamine/toxicity , Transcription Factor CHOP/genetics , Animals , Dopamine/biosynthesis , Dopamine Agents/pharmacology , Dopaminergic Neurons/drug effects , Dopaminergic Neurons/metabolism , Endoplasmic Reticulum Chaperone BiP , Gene Expression Regulation/drug effects , Mice , Receptors, Dopamine D1/metabolism , Transcription Factor CHOP/biosynthesis
10.
Mol Cell Biochem ; 333(1-2): 57-64, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19626424

ABSTRACT

It is known that the nervous system significantly attenuates systemic inflammatory responses through the parasympathetic nervous system. Furthermore, it has been reported that the alpha 7 subunit of a nicotinic acetylcholine receptor is required for a cholinergic inhibition against cytokine synthesis in a macrophage. As antigen-presenting cells (APCs) play a central role in the generation of primary T cell responses and the maintenance of immunity, in this study, we investigated the expression level of nicotinic receptors of a p53-deficient APC cell line (JawsII) derived from a mouse bone marrow. We showed that stimulation of the JawsII cells with lipopolysaccharide (LPS) and tumor necrosis factor alpha (TNF-alpha) led increase of CD80 and CD86 expression while diminishment of the surface nicotinic receptor. On the other hand, stimulation of nicotinic receptor had no effect on these phenomena. Furthermore, we examined the ability of the cells to release cytokine when stimulated with both nicotine and LPS and showed that the stimulation with LPS augmented the secretion of IL-1a, IL-1b, IL-6, and TNF-alpha. These results suggested that nicotinic stimulation had no effect on the diminishment of alpha 7 nicotinic acetylcholine receptor on JawsII cells by LPS stimulation.


Subject(s)
Antigen-Presenting Cells/cytology , Cytokines/metabolism , Gene Expression Regulation/drug effects , Receptors, Nicotinic/genetics , Animals , Cell Differentiation , Cell Line , Inflammation Mediators , Lipopolysaccharides/pharmacology , Mice , Nicotine/pharmacology
11.
FEBS Lett ; 582(16): 2365-70, 2008 Jul 09.
Article in English | MEDLINE | ID: mdl-18538670

ABSTRACT

We have previously reported that Monad, a novel WD40 repeat protein, potentiates apoptosis induced by tumor necrosis factor-alpha(TNF-alpha) and cycloheximide (CHX). By affinity purification and mass spectrometry, we identified RNA polymerase II-associated protein 3 (RPAP3) as a binding protein of Monad. Overexpression of RPAP3 in HEK 293 potentiated caspase-3 activation and apoptosis induced by TNF-alpha and CHX. In addition, knockdown of RPAP3 by RNA interference resulted in a significant reduction of apoptosis induced by TNF-alpha and CHX in HEK293 and HeLa cells. These results raise the possibility that RPAP3, together with Monad, may function as a novel modulator of apoptosis pathway.


Subject(s)
Apoptosis Regulatory Proteins/metabolism , Apoptosis , Carrier Proteins/physiology , Amino Acid Sequence , Carrier Proteins/chemistry , Carrier Proteins/genetics , Cell Line , Cloning, Molecular , Humans , Molecular Sequence Data , Protein Structure, Tertiary , RNA, Messenger/metabolism , Repetitive Sequences, Amino Acid , Tissue Distribution
12.
J Biol Chem ; 282(16): 11786-94, 2007 Apr 20.
Article in English | MEDLINE | ID: mdl-17324936

ABSTRACT

We have previously shown that procaspase-3 exists in a high molecular weight complex in neonatal rat brain. Here, we purify and identify the protein that interacts with procaspase-3 from rat neonatal cortex. We searched binding proteins to procaspase-3 from a cytosolic extract of neonatal rat brain using chromatogram, two-dimensional gel electrophoresis, and far Western immunoblot. Analysis by tandem mass spectrometry identified the protein as a regulatory subunit of calcineurin (calcineurin B). Overexpression of calcineurin B in HEK293 cells potentiated processing of caspase-3 and apoptosis triggered by tumor necrosis factor-alpha and cycloheximide treatment. In a cell-free system, overexpression of calcineurin B in HEK293 cells markedly increased processing of caspase-3 by cytochrome c. Immunodepletion of calcineurin B from cytosolic extracts from Jurkat cells decreased processing of caspase-3 by cytochrome c. Knockdown of calcineurin B by RNA interference resulted in reduced apoptosis in HEK293 cells but not in caspase-3-deficient MCF-7 cells. These results suggest that calcineurin B potentiates the activation of procaspase-3 by accelerating its proteolytic maturation.


Subject(s)
Calcineurin/physiology , Caspase 3/metabolism , Animals , Apoptosis , Brain/metabolism , Calcineurin/metabolism , Caspase 9/metabolism , Cell Line, Tumor , Cycloheximide/pharmacology , Cytochromes c/metabolism , Enzyme Activation , Humans , Rats , Rats, Wistar , Tumor Necrosis Factor-alpha/metabolism
13.
Biochem Biophys Res Commun ; 342(2): 568-72, 2006 Apr 07.
Article in English | MEDLINE | ID: mdl-16487927

ABSTRACT

WD40 repeat proteins have a wide range of diverse biological functions including signal transduction, cell cycle regulation, RNA splicing, and transcription. Here we report the identification and characterization of a novel human WD40 repeat protein, Monad. Monad is unique, since it contains only two WD40 repeats. Monad is widely expressed in human tissues with the highest expression in testis. Overexpression of Monad in HEK293 cells potentiated apoptosis and caspase-3 activation induced by tumor necrosis factor-alpha and cycloheximide. These results raise the possibility that Monad may function as a novel modulator of apoptosis pathway.


Subject(s)
Apoptosis Regulatory Proteins/physiology , Apoptosis/physiology , Microfilament Proteins/physiology , Tumor Necrosis Factor-alpha/physiology , Amino Acid Sequence , Animals , Apoptosis Regulatory Proteins/genetics , Caspase 3 , Caspases/metabolism , Cell Line , Humans , Male , Mice , Molecular Sequence Data , Organ Specificity/genetics , RNA, Messenger/biosynthesis , Rats , Repetitive Sequences, Amino Acid , Sequence Alignment , Testis/metabolism
14.
Neurochem Int ; 45(5): 753-8, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15234119

ABSTRACT

Pur alpha is an abundant protein in the brain and binds to a (GGN)n sequence, PUR element. It has been shown that Pur alpha not only interacts with single stranded DNA and RNA, but also with various proteins. In the present study, we tried to search for Pur alpha-binding proteins (PurBPs) in mouse brain by the overlay assay with GST-Pur alpha as a ligand. Three PurBPs of 35, 38 and 40 kDa were found mostly in the nuclear extract (N.Ext.) and they were not detected by the pretreatment of N.Ext. with trypsin, but not with RNase or DNase. The three PurBPs disappeared by the addition of ssCRE (single stranded cAMP response element) containing a PUR element, but not by DeltaGGN ssCRE (deletion of the PUR element from the ssCRE). The PurBPs were abundantly expressed in the brain as Pur alpha. We also determined a region in Pur alpha which is required for the association with the PurBPs by using deletion mutants of Pur alpha. These biochemical properties of the PurBPs are different from the reported nuclear Pur alpha-binding proteins such as Sp1 and pRb.


Subject(s)
Brain Chemistry/physiology , DNA-Binding Proteins/metabolism , Nerve Tissue Proteins/metabolism , Animals , Brain/cytology , Cell Nucleus/chemistry , Cyclic AMP Response Element-Binding Protein/genetics , Cyclic AMP Response Element-Binding Protein/metabolism , DNA-Binding Proteins/genetics , Electrophoresis, Polyacrylamide Gel , Escherichia coli/metabolism , Ligands , Male , Mice , Nerve Tissue Proteins/genetics , Neurons/metabolism , Protein Binding , Subcellular Fractions/chemistry
15.
Mol Cell Biochem ; 248(1-2): 77-83, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12870657

ABSTRACT

The Ku autoantigen/KARP-1 (Ku86 autoantigen related protein-1) plays an important role in the double-strand break repair of mammalian DNA as a DNA-binding component of DNA-dependent protein kinase (DNA-PK) complex. KARP-1 is differently transcribed from the human Ku86 autoantigen gene locus and it is implicated in the control of DNA-dependent protein kinase activity. We cloned rKAB1, a rat homolog of KAB1 (KARP-1 binding protein 1 of human) from a rat hippocampal cDNA library. rKAB1 mRNA was specifically expressed in the brain and the thymus. EGFP-tagged rKAB1 protein localized in cell nucleus and in the condensed chromosome during the mitotic cell division. We found that rKAB1 works as a protective protein against cell damage by oxidative stress.


Subject(s)
Carrier Proteins/chemistry , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cell Nucleus/metabolism , DNA Helicases , Oxygen/metabolism , Amino Acid Sequence , Animals , Antigens, Nuclear/biosynthesis , Blotting, Northern , Brain/metabolism , Carrier Proteins/physiology , Cell Death , Cell Line , Cell Survival , Chromosomes/ultrastructure , Cloning, Molecular , DNA/metabolism , DNA Repair , DNA-Activated Protein Kinase , DNA-Binding Proteins/biosynthesis , Gene Library , HeLa Cells , Hippocampus/metabolism , Humans , Hydrogen Peroxide/pharmacology , Ku Autoantigen , Mice , Molecular Sequence Data , NIH 3T3 Cells , Nuclear Proteins , Oxidative Stress , Precipitin Tests , Protein Binding , Protein Serine-Threonine Kinases/metabolism , RNA, Messenger/metabolism , Rats , Thymus Gland/metabolism , Tissue Distribution , Transfection
16.
Mol Cell Biochem ; 246(1-2): 179-85, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12841360

ABSTRACT

Amida was first isolated from a rat hippocampal cDNA library as an Arc-associated protein. Although previous studies have shown that Amida mRNA is predominantly expressed and developmentally regulated in rat testis and overexpression induces apoptosis, the function of Amida remains unclear. In this study, we found that overexpression of Amida inhibited cell growth. Flow cytometry analysis showed that Amida caused cell cycle inhibition in the S-phase and blocked cell cycle from entry into mitosis. Attempting to elucidate Amida effect on the cell cycle, we found that Amida was interacted with Cdc2 in mitosis and Amida's overexpression resulted in a decrease in Cdc2 kinase activity. In addition, Amida showed DNA-binding ability with DNA-affinity column chromatography. A region (aa, 76-189) between the two nuclear localization signals was found to be responsible for cell growth inhibition and DNA-binding activity, implying that DNA-binding activity may be necessary for Amida to repress cell cycle. Moreover, Amida was phosphorylated by Cdc2 kinase in vitro and Ser-180 of Amida was identified as the phosphorylation site. Furthermore, AmidaS180G (eliminate phosphorylation of Ser-180) showed stronger DNA-binding activity. Taken together, the data suggest that Amida may play an important role in cell cycle and may be partly regulated by Cdc2 kinase.


Subject(s)
CDC2 Protein Kinase/metabolism , Cell Cycle/physiology , Nuclear Proteins/physiology , Animals , Base Sequence , Binding Sites/genetics , COS Cells , DNA, Complementary/genetics , DNA, Complementary/metabolism , Mitosis , Mutagenesis, Site-Directed , Nuclear Proteins/chemistry , Nuclear Proteins/genetics , Phosphorylation , Rats , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Serine/chemistry , Transfection
17.
Proc Natl Acad Sci U S A ; 100(10): 5634-9, 2003 May 13.
Article in English | MEDLINE | ID: mdl-12719531

ABSTRACT

Several reports have described an activity that modifies nitrotyrosine-containing proteins and their immunoreactivity to nitrotyrosine Abs. Without knowing the product of the reaction, this new activity has been called a "denitrase." In those studies, some nonspecific proteins, which have multiple tyrosine residues, e.g., albumin, were used as a substrate. Therefore, the studies were based on an unknown mechanism of reaction and potentially a high background. To solve these problems, one of the most important things is to find a more suitable substrate for assay of the enzyme. We developed an assay strategy for determining the substrate for denitrase combining 2D-gel electrophoresis and an on-blot enzyme assay. The resulting substrate from RAW 264.7 cells was Histone H1.2, an isoform protein of linker histone. Histone H1.2 has only one tyrosine residue in the entire molecule, which ensures the exact position of the substrate to be involved. It has been reported that Histones are the most prominent nitrated proteins in cancer tissues. It was also demonstrated that tyrosine nitration of Histone H1 occurs in vivo. These findings lead us to the idea that Histone H1.2 might be an intrinsic substrate for denitrase. We nitrated recombinant and purified Histone H1.2 chemically and subjected it to an on-blot enzyme assay to characterize the activity. Denitrase activity behaved as an enzymatic activity because the reaction was time dependent and was destroyed by heat or trypsin treatment. The activity was shown to be specific for Histone H1.2, to differ from proteasome activity, and to require no additional cofactors.


Subject(s)
Histones/metabolism , Hydrolases/metabolism , Proteins/metabolism , Tyrosine/analogs & derivatives , Tyrosine/metabolism , Animals , Cell Line , Cell Membrane/enzymology , Deoxyribonucleases/metabolism , Kinetics , Macrophages , Mice , Peroxynitrous Acid/pharmacology , Proteins/chemistry , Substrate Specificity , Trypsin/metabolism
18.
Nitric Oxide ; 8(1): 15-25, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12586537

ABSTRACT

NO in vivo has both beneficial and nonbeneficial effects depending on site and concentration. Peroxynitrite, resulting from the reaction of NO with superoxide radical, causes cellular damage. Nitrotyrosine, end product of NO's toxic effects on cellular proteins, is a stable compound that can be used to detect evidence of harmful quantities of NO. We sought to detect nitrotyrosine in coronary arterioles of DBA/2 mice injected intraperitoneally with Lactobacillus casei cell wall. The inflammatory response induced occurred in perivascular fashion and involved mainly macrophages. It was variable according to time points, being severe on days 10 and 14 and mild to moderate on days 3 and 7. Few basal inflammatory cells appeared in controls injected with phosphate-buffered saline. Western immunoblots of homogenized hearts on days 10 and 14 demonstrated specific nitrated proteins. Immunohistochemistry of frozen sections of diseased hearts showed positive immunoreactivity for nitrotyrosine in coronary arterioles at the same time points. These findings were absent in the controls. We also determined the expression of inducible nitric oxide synthase (iNOS) in controls on days 10 and 14. iNOS colocalized with nitrotyrosine in perivascular macrophages and coronary arterioles of treated mice. Additionally, aneurysms were found on day 10 and intracardiac hemorrhage with consequent death on day 14. These observations supply evidence that NO through its reactive product, peroxynitrite, and its antigen/tissue marker, nitrotyrosine, is directly involved in coronary arteritis and aneurysm development in mice models of Kawasaki disease (KD). This article shows that macrophages are central to this and bolsters the likelihood of L. casei being the cause of KD.


Subject(s)
Aneurysm/etiology , Aneurysm/metabolism , Mucocutaneous Lymph Node Syndrome/etiology , Mucocutaneous Lymph Node Syndrome/metabolism , Nitric Oxide/metabolism , Tyrosine/analogs & derivatives , Vasculitis/etiology , Vasculitis/metabolism , Aneurysm/pathology , Animals , Blotting, Western , Cell Wall/immunology , Coronary Vessels/enzymology , Coronary Vessels/metabolism , Coronary Vessels/pathology , Disease Models, Animal , Hemorrhage/pathology , Immunohistochemistry , Inflammation/pathology , Lacticaseibacillus casei/cytology , Lacticaseibacillus casei/immunology , Macrophages/enzymology , Male , Mice , Mucocutaneous Lymph Node Syndrome/enzymology , Mucocutaneous Lymph Node Syndrome/pathology , Myocardium/pathology , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Peroxynitrous Acid/metabolism , Thrombosis/pathology , Time Factors , Tyrosine/metabolism , Vasculitis/enzymology , Vasculitis/pathology
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