90 research outputs found

    Two solanesyl diphosphate synthases with different subcellular localizations and their respective physiological roles in Oryza sativa

    Get PDF
    Long chain prenyl diphosphates are crucial biosynthetic precursors of ubiquinone (UQ) in many organisms, ranging from bacteria to humans, as well as precursors of plastoquinone in photosynthetic organisms. The cloning and characterization of two solanesyl diphosphate synthase genes, OsSPS1 and OsSPS2, in Oryza sativa is reported here. OsSPS1 was highly expressed in root tissue whereas OsSPS2 was found to be high in both leaves and roots. Enzymatic characterization using recombinant proteins showed that both OsSPS1 and OsSPS2 could produce solanesyl diphosphates as their final product, while OsSPS1 showed stronger activity than OsSPS2. However, an important biological difference was observed between the two genes: OsSPS1 complemented the yeast coq1 disruptant, which does not form UQ, whereas OsSPS2 only very weakly complemented the growth defect of the coq1 mutant. HPLC analyses showed that both OsSPS1 and OsSPS2 yeast transformants produced UQ9 instead of UQ6, which is the native yeast UQ. According to the complementation study, the UQ9 levels in OsSPS2 transformants were much lower than that of OsSPS1. Green fluorescent protein fusion analyses showed that OsSPS1 localized to mitochondria, while OsSPS2 localized to plastids. This suggests that OsSPS1 is involved in the supply of solanesyl diphosphate for ubiquinone-9 biosynthesis in mitochondria, whereas OsSPS2 is involved in providing solanesyl diphosphate for plastoquinone-9 formation. These findings indicate that O. sativa has a different mechanism for the supply of isoprenoid precursors in UQ biosynthesis from Arabidopsis thaliana, in which SPS1 provides a prenyl moiety for UQ9 at the endoplasmic reticulum

    FAT is a component of glomerular slit diaphragms

    Get PDF
    FAT is a component of glomerular slit diaphragms.BackgroundSlit diaphragms are intercellular junctions of podocytes of the renal glomerulus. The molecular composition of slit diaphragms is still elusive. Slit diaphragms are characterized by the presence of a wide intercellular space. The morphological feature is shared by desmosomes and adherens junctions, which contain members of the cadherin superfamily. Thus, we have hypothesized that some components of slit diaphragms belong to the cadherin superfamily. Consequently, we have isolated cDNA encoding FAT from reverse-transcribed (RT) glomerular cDNA by homology polymerase chain reaction (PCR) using primers based on conserved sequences in cadherin molecules. FAT is a novel member of the cadherin superfamily with 34 tandem cadherin-like extracellular repeats, and it closely resembles the Drosophila tumor suppressor fat.MethodsExpression of FAT was examined in glomeruli of the adult rat kidney by the ribonuclease protection assay and in situ hybridization. To localize the FAT protein in podocytes minutely, we prepared affinity-purified antibody against FAT by immunizing rabbits against an oligopeptide corresponding to the C-terminal 20 amino acids.ResultsExpression of FAT mRNA was detected in total RNA from glomeruli. In situ hybridization revealed significant signals in podocytes. Western blot analysis using solubilized glomeruli showed a single band, in which the molecular weight was more than 500 kD. Immunostaining of cultured epithelial cells from rat kidney (NRK52E) revealed FAT accumulation in cell–cell contact sites. In the glomerulus, FAT staining was observed distinctly along glomerular capillary walls. Double-label immunostaining using monoclonal antibody against slit diaphragms (mAb 5-1-6) showed identical localization of anti-FAT antibody and mAb 5-1-6. Furthermore, the double-label immunogold technique with ultrathin cryosections demonstrated that gold particles for FAT cytoplasmic domain were located at the base of slit diaphragms labeled by mAb 5-1-6 and that the cytoplasmic domain of FAT colocalized with ZO-1, a cytoplasmic component associated with slit diaphragms.ConclusionThe molecular structure of FAT and its colocalization with 5-1-6 antigen and ZO-1 indicate that FAT is a component of slit diaphragms

    Stabilization by Fusion to the C-terminus of Hyperthermophile Sulfolobus tokodaii RNase HI: A Possibility of Protein Stabilization Tag

    Get PDF
    RNase HI from the hyperthermophile Sulfolobus tokodaii (Sto-RNase HI) is stabilized by its C-terminal residues. In this work, the stabilization effect of the Sto-RNase HI C-terminal residues was investigated in detail by thermodynamic measurements of the stability of variants lacking the disulfide bond (C58/145A), or the six C-terminal residues (ΔC6) and by structural analysis of ΔC6. The results showed that the C-terminal does not affect overall structure and stabilization is caused by local interactions of the C-terminal, suggesting that the C-terminal residues could be used as a “stabilization tag.” The Sto-RNase HI C-terminal residues (-IGCIILT) were introduced as a tag on three proteins. Each chimeric protein was more stable than its wild-type protein. These results suggested the possibility of a simple stabilization technique using a stabilization tag such as Sto-RNase HI C-terminal residues

    Delphi Method Consensus-Based Identification of Primary Trauma Care Skills Required for General Surgeons in Japan

    Get PDF
    Purpose General surgeons at regional hospitals should have the primary trauma care skills necessary to treat critically ill trauma patients to withstand transfer. This study was conducted to identify a consensus on primary trauma care skills for general surgeons. Methods An initial list of acute care surgical skills was compiled, and revised by six trauma experts (acute care surgeons); 33 skills were nominated for inclusion in the Delphi consensus survey. Participants (councilors of the Japanese Society for Acute Care Surgery) were presented with the list of 33 trauma care skills and were asked (using web-based software) to rate how strongly they agreed or disagreed (using a 5-point Likert scale) with the necessity of each skill for a general surgeon. The reliability of consensus was predefined as Cronbach’s α ≥ 0.8, and trauma care skills were considered as primarily required when rated 4 (agree) or 5 (strongly agree) by ≥ 80% participants. Results There were 117 trauma care specialists contacted to participate in the Delphi consensus survey panel. In the 1st round, 85 specialists participated (response rate: 72.6%). In the 2nd round, 66 specialists participated (response rate: 77.6%). Consensus was achieved after two rounds, reliability using Cronbach’s α was 0.94, and 34 items were identified as primary trauma care skills needed by general surgeons. Conclusion A consensus-based list of trauma care skills required by general surgeons was developed. This list can facilitate the development of a new trauma training course which has been optimized for general surgeons

    Corrigendum: Use of the index of pulmonary vascular disease for predicting longterm outcome of pulmonary arterial hypertension associated with congenital heart disease

    Get PDF

    Use of the index of pulmonary vascular disease for predicting long-term outcome of pulmonary arterial hypertension associated with congenital heart disease

    Get PDF
    AimsLimited data exist on risk factors for the long-term outcome of pulmonary arterial hypertension (PAH) associated with congenital heart disease (CHD-PAH). We focused on the index of pulmonary vascular disease (IPVD), an assessment system for pulmonary artery pathology specimens. The IPVD classifies pulmonary vascular lesions into four categories based on severity: (1) no intimal thickening, (2) cellular thickening of the intima, (3) fibrous thickening of the intima, and (4) destruction of the tunica media, with the overall grade expressed as an additive mean of these scores. This study aimed to investigate the relationship between IPVD and the long-term outcome of CHD-PAH.MethodsThis retrospective study examined lung pathology images of 764 patients with CHD-PAH aged <20 years whose lung specimens were submitted to the Japanese Research Institute of Pulmonary Vasculature for pulmonary pathological review between 2001 and 2020. Clinical information was collected retrospectively by each attending physician. The primary endpoint was cardiovascular death.ResultsThe 5-year, 10-year, 15-year, and 20-year cardiovascular death-free survival rates for all patients were 92.0%, 90.4%, 87.3%, and 86.1%, respectively. The group with an IPVD of ≥2.0 had significantly poorer survival than the group with an IPVD <2.0 (P = .037). The Cox proportional hazards model adjusted for the presence of congenital anomaly syndromes associated with pulmonary hypertension, and age at lung biopsy showed similar results (hazard ratio 4.46; 95% confidence interval: 1.45–13.73; P = .009).ConclusionsThe IPVD scoring system is useful for predicting the long-term outcome of CHD-PAH. For patients with an IPVD of ≥2.0, treatment strategies, including choosing palliative procedures such as pulmonary artery banding to restrict pulmonary blood flow and postponement of intracardiac repair, should be more carefully considered

    Numerical Study on Wave Propagation in a Branched Lattice of LC Circuit

    Get PDF
    Linear and nonlinear wave propagations of soliton-like pulse waves are studies by solving the second order ordinary differential equations numerically. The model in which the wave propagations are considered is the one-dimensional infinite lattice of an LC (inductor-capacitor) circuit with a branching point. The behaviors of the soliton-like pulse waves before and after passing through the branching point are observed in detail. These observations show that after passing through the point the original waves are split into two, reflected and transmitted, for both the linear and nonlinear cases. Although, in general, the behaviors of these two waves are very complex and difficult to analyze, a theoretical analysis using the continuous approximation to the model is possible in some cases
    corecore