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

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

From Traditional Factor Analysis Model to Causal Modeling by SEM : Exemplifying the Scale for the Measurement of Anthrophobic Tendency and the Interpersonal Stress-coping Inventory

心理学研究分野での構成概念の次元は、因子間に相関がある因子分析モデルのもとで、主に探索されてきている。Cattell(1966) は、因子間の相関的な関係性を、同じ水準だけではなく異なった水準あるいは層における因子の間での因果モデルヘと発展させた。McArdle(1984) によって示されたように、Cattellのアイデイアは構造方程式モデリングの分野において実現されてきている。本稿の目的は、構成概念妥当性を確認することへの構造方程式モデリングの有効性を示すことである。研究Iでは、堀井・小川(1996、1997) による対人恐怖心性の6因子を探索的因子分析で抽出した。これらの6因子を確認するために、項目による7種類の因子分析的モデルと下位尺度による5つのモデルと1つの因果モデルがAomsによって推定された。研究Ⅱでは、加藤(2000) による対人ストレスコーピング尺度の6因子が同様に抽出された。この尺度からの15項目に対して、6種類の因子分析モデルと1つの因果モデルが分析された。2つの研究共に、最も適合度の高いモデルは因果モデルであった。これらの結果の意味が議論された。The dimensions of the constructs in the fields of psychological research have mostly been explored under the factor analysis model with correlations among factors. Cattell (1966) had expanded such correlational relationships among factors to the causal modeling between factors not only at the same level also at different levels or strata. As indicated by McArdle (1984) Cattell\u27s idea has been actual in the field of structural equation modeling. The purpose of this paper is to demonstrate the utility of structural equation modeling for confirming the construct validities. In study I, the six factors of anthrophobic tendency by Hoii & Ogawa (1996, 1997) are extracted by the exploratory factor analysis. To confirm the structure of these six factors, seven kinds of factor analytical models using items and five models and one causal model using sub-scales are estimated by the Amos. In study II, the six factors of the interpersonal stress-coping inventory by Kato (2000) are also extracted. For the 15 items from this inventory, six kinds of factor analytical models and one causal model are analyzed. In both studies, the model that fits best is the causal model. The implications of these findings are discussed

Targeted therapy against Bcl-2-related proteins in breast cancer cells

INTRODUCTION: Bcl-2 and Bcl-xL confer resistance to apoptosis, thereby reducing the effectiveness of chemotherapy. We examined the relationship between the expression of Bcl-2 and Bcl-xL and chemosensitivity of breast cancer cells, with the aim of developing specific targeted therapy. METHODS: Four human breast cancer cell lines were examined, and the effects of antisense (AS) Bcl-2 and AS Bcl-xL phosphorothioate oligodeoxynucleotides (ODNs) on chemosensitivity were tested in vitro and in vivo. Chemosensitivity was evaluated by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay, and the antitumor effect was assessed in vivo by the success of xenograft transplantation into athymic mice. RESULTS: Treatment with AS Bcl-2 and Bcl-xL ODNs resulted in a sequence-specific decrease in protein expression, compared with controls. Treatment of BT-474, ZR-75-1, and MDA-MB-231 cells with AS Bcl-2 increased chemosensitivity to doxorubicin (DOX), mitomycin C (MMC), paclitaxel (TXL), and docetaxel (TXT). Transfection of the Bcl-2 gene into MDA-MB-453 cells decreased sensitivity to DOX and MMC. Treatment of MDA-MB-231, BT-474, and ZR-75-1 cells with AS Bcl-xL increased chemosensitivity to DOX, MMC and taxanes to a smaller extent than AS Bcl-2. This occurred in the setting of increased Bax and cleaved poly(ADP-ribose) polymerase, as well as decreased Bcl-2 and pAkt. AS Bcl-2 ODNs induced splenomegaly in association with increased serum IL-12, which was attenuated by methylation of the CpG motifs of AS Bcl-2; however, methylated CpG failed to negate the increased antitumor effect of AS Bcl-2. Bcl-2 and Bcl-xL, to a smaller extent, are major determinants of chemosensitivity in breast cancer cells. CONCLUSION: Targeted therapy against Bcl-2 protein with the use of AS ODNs might enhance the effects of chemotherapy in patients with breast cancer

Non-human primate model of amyotrophic lateral sclerosis with cytoplasmic mislocalization of TDP-43

Amyotrophic lateral sclerosis is a fatal neurodegenerative disease characterized by progressive motoneuron loss. Redistribution of transactive response deoxyribonucleic acid-binding protein 43 from the nucleus to the cytoplasm and the presence of cystatin C-positive Bunina bodies are considered pathological hallmarks of amyotrophic lateral sclerosis, but their significance has not been fully elucidated. Since all reported rodent transgenic models using wild-type transactive response deoxyribonucleic acid-binding protein 43 failed to recapitulate these features, we expected a species difference and aimed to make a non-human primate model of amyotrophic lateral sclerosis. We overexpressed wild-type human transactive response deoxyribonucleic acid-binding protein 43 in spinal cords of cynomolgus monkeys and rats by injecting adeno-associated virus vector into the cervical cord, and examined the phenotype using behavioural, electrophysiological, neuropathological and biochemical analyses. These monkeys developed progressive motor weakness and muscle atrophy with fasciculation in distal hand muscles first. They also showed regional cytoplasmic transactive response deoxyribonucleic acid-binding protein 43 mislocalization with loss of nuclear transactive response deoxyribonucleic acid-binding protein 43 staining in the lateral nuclear group of spinal cord innervating distal hand muscles and cystatin C-positive cytoplasmic aggregates, reminiscent of the spinal cord pathology of patients with amyotrophic lateral sclerosis. Transactive response deoxyribonucleic acid-binding protein 43 mislocalization was an early or presymptomatic event and was later associated with neuron loss. These findings suggest that the transactive response deoxyribonucleic acid-binding protein 43 mislocalization leads to α-motoneuron degeneration. Furthermore, truncation of transactive response deoxyribonucleic acid-binding protein 43 was not a prerequisite for motoneuronal degeneration, and phosphorylation of transactive response deoxyribonucleic acid-binding protein 43 occurred after degeneration had begun. In contrast, similarly prepared rat models expressed transactive response deoxyribonucleic acid-binding protein 43 only in the nucleus of motoneurons. There is thus a species difference in transactive response deoxyribonucleic acid-binding protein 43 pathology, and our monkey model recapitulates amyotrophic lateral sclerosis pathology to a greater extent than rodent models, providing a valuable tool for studying the pathogenesis of sporadic amyotrophic lateral sclerosis

A general framework for estimation and inference of geographically weighted regression models: 2. Spatial association and model specification tests

Spatial association effects, perhaps the most important concern in the analysis of spatial data, have been amply studied from a global perspective in the exploratory and modeling domains, and more recently also from a local perspective in the realm of exploratory data analysis. In a local modeling framework, however, the issue of how to detect and model spatial association by using geographically weighted regression (GWR) remains largely unresolved. In this paper we exploit a recent development that casts GWR as a model of locational heterogeneity, to formulate a general model of spatial effects that includes as special cases GWR with a spatially lagged objective variable and GWR with spatial error autocorrelation. The approach also permits the derivation of formal tests against several forms of model misspecification, including locational heterogeneity in global models, and spatial error autocorrelation in GWR models. Application of these results is exemplified with a case study.

Correction to: Targeted therapy against Bcl-2-related proteins in breast cancer cells

After the publication of this work [1] errors were noticed in Figs. 1a, 6a, and 8a—in which the β-actin bands were mistakenly presented