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61.
Wu X Itoh N Taniguchi T Nakanishi T Tatsu Y Yumoto N Tanaka K 《Archives of biochemistry and biophysics》2003,420(1):114-120
Zinc is an essential trace element that increases osteoblast numbers and bone formation. However, the mechanisms involved in the Zn-induced differentiation of osteoblasts are poorly understood. We examined the roles of L-ascorbic acid (AA) and its transporter, sodium-dependent vitamin C transporter (SVCT) 2, in the Zn-induced expression of osteoblastic differentiation markers. Zinc time- and dose-dependently induced SVCT2 mRNA expression in the absence or presence of AA. Western blotting and kinetic assays showed that Zn increased functional SVCT2 protein levels and AA transport. In the presence of AA, 50 microM Zn enhanced mRNA expression of the osteoblastic differentiation markers alkaline phosphatase, alpha(1)(I) procollagen, osteopontin (OPN), and osteocalcin (OCN) by 3.9-, 3.8-, 3.3-, and 3.5-fold, respectively; in the absence of AA, the Zn-induced increase was 2.8-, 2.5-, 1.3-, and 1.1-fold, respectively. These findings suggest that AA and SVCT2 mediate Zn-induced OPN and OCN expression and partly regulate Zn-induced osteoblastic differentiation. 相似文献
62.
Hiroyuki Koga Haruka Fujitani Yoshiaki Morino Norio Miyamoto Jun Tsuchimoto Tomoko F. Shibata Masafumi Nozawa Shuji Shigenobu Atsushi Ogura Kazunori Tachibana Masato Kiyomoto Shonan Amemiya Hiroshi Wada 《PloS one》2016,11(2)
Over the course of evolution, the acquisition of novel structures has ultimately led to wide variation in morphology among extant multicellular organisms. Thus, the origins of genetic systems for new morphological structures are a subject of great interest in evolutionary biology. The larval skeleton is a novel structure acquired in some echinoderm lineages via the activation of the adult skeletogenic machinery. Previously, VEGF signaling was suggested to have played an important role in the acquisition of the larval skeleton. In the present study, we compared expression patterns of Alx genes among echinoderm classes to further explore the factors involved in the acquisition of a larval skeleton. We found that the alx1 gene, originally described as crucial for sea urchin skeletogenesis, may have also played an essential role in the evolution of the larval skeleton. Unlike those echinoderms that have a larval skeleton, we found that alx1 of starfish was barely expressed in early larvae that have no skeleton. When alx1 overexpression was induced via injection of alx1 mRNA into starfish eggs, the expression patterns of certain genes, including those possibly involved in skeletogenesis, were altered. This suggested that a portion of the skeletogenic program was induced solely by alx1. However, we observed no obvious external phenotype or skeleton. We concluded that alx1 was necessary but not sufficient for the acquisition of the larval skeleton, which, in fact, requires several genetic events. Based on these results, we discuss how the larval expression of alx1 contributed to the acquisition of the larval skeleton in the putative ancestral lineage of echinoderms. 相似文献
63.
G-protein-coupled receptor (GPR) 3 is a member of the GPR family that constitutively activates adenylate cyclase. We have reported that the expression of GPR3 in cerebellar granular neurons (CGNs) contributes to neurite outgrowth and modulates neuronal proliferation and survival. To further identify its role, we have analyzed the precise distribution and local functions of GPR3 in neurons. The fluorescently tagged GPR3 protein was distributed in the plasma membrane, the Golgi body, and the endosomes. In addition, we have revealed that the plasma membrane expression of GPR3 functionally up-regulated the levels of PKA, as measured by a PKA FRET indicator. Next, we asked if the PKA activity was modulated by the expression of GPR3 in CGNs. PKA activity was highly modulated at the neurite tips compared to the soma. In addition, the PKA activity at the neurite tips was up-regulated when GPR3 was transfected into the cells. However, local PKA activity was decreased when endogenous GPR3 was suppressed by a GPR3 siRNA. Finally, we determined the local dynamics of GPR3 in CGNs using time-lapse analysis. Surprisingly, the fluorescent GPR3 puncta were transported along the neurite in both directions over time. In addition, the anterograde movements of the GPR3 puncta in the neurite were significantly inhibited by actin or microtubule polymerization inhibitors and were also disturbed by the Myosin II inhibitor blebbistatin. Moreover, the PKA activity at the tips of the neurites was decreased when blebbistatin was administered. These results suggested that GPR3 was transported along the neurite and contributed to the local activation of PKA in CGN development. The local dynamics of GPR3 in CGNs may affect local neuronal functions, including neuronal differentiation and maturation. 相似文献
64.
Pyrophosphate-dependent phosphofructokinase from pollen: properties and possible roles in sugar metabolism 总被引:1,自引:0,他引:1
To evaluate the role of pyrophosphate-dependent phosphofructokinase (PFP. EC 2.7.1.90) in the sugar metabolism of pollen. its occurrence and properties were studied in pollen grains of several plants including camellia ( Camellia japonica L.). In all pollen samples, PFP was strongly activated by fructose-2,6-bisphosphate (F2,6BP), and the activity of F2,6BP-activated PFP was higher than that of phosphofructokinase (PFK. EC 2.7.1.11). PFP partially purified from camellia pollen required Mg2+ for activity with an optimum at 1 m M . and was almost unaflected by a variety of metabolites at 1 m M . Its molecular mass was around 220 kDa, and apparent Km values for F6P, PPi . F1, 6BP and Pi were 294, 4, 20 and 580 u M , respectively. The levels of F2.6BP. PPi and F6P in camellia pollen were sufficent to support the forward reaction by PFP, and PFP, was 20- to 40-fold more active than PFK during pollen growth. These results suggest that pollen PFP plays a role in glycolysis but not gluconeogenesis. and the possible relevance of this to pollen tube growth is discussed. 相似文献
65.
Ohara Chisato Sekiguchi Atsushi Takakura Shu Endo Yuka Tamura Naho Kikuchi Hiroe Maruo Kazushi Sugawara Norio Hatano Kenji Kawanishi Hitomi Funaba Misako Sugawara Ayako Nohara Nobuhiro Kawai Keisuke Fukudo Shin Sudo Nobuyuki Cooper Zafra Yoshiuchi Kazuhiro Ando Tetsuya 《BioPsychoSocial medicine》2020,14(1):1-3
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017. 相似文献
66.
67.
Tadashi Itagaki Naomi Motoyoshi Hiroko Kobayashi Yoshio Ogawa Dai Hirose Norio Inokuchi 《Mycoscience》2013,54(3):188-197
A gene encoding a ribonuclease T2 (RNase T2) family enzyme, RNHe30, was cloned from Hericium erinaceum by PCR. The deduced amino acid sequence from the complimentary DNA (cDNA) (1074 bp) encodes a 302-aa protein (RNase He30) that has the consensus amino acid sequences of RNase T2 family enzymes including the putative signal peptide. The presence of five introns in the genomic DNA was confirmed by comparison of the cDNA and genomic DNA sequences. The promoter region contains a putative CAAT box and a consensus TATA box. Genes coding homologous enzymes were also identified in various other basidiomycetes. A phylogenetic tree of RNase T2s from these fungi was constructed from a multiple alignment of the deduced amino acid sequences. The tree showed that the enzymes were divided into two main groups. 相似文献
68.
Daiki Miki Hidenori Ochi Atsushi Takahashi C. Nelson Hayes Yuji Urabe Hiromi Abe Tomokazu Kawaoka Masataka Tsuge Nobuhiko Hiraga Michio Imamura Yoshiiku Kawakami Hiroshi Aikata Shoichi Takahashi Norio Akuta Fumitaka Suzuki Kenji Ikeda Hiromitsu Kumada Yoshiyasu Karino Joji Toyota Tatsuhiko Tsunoda Michiaki Kubo Naoyuki Kamatani Yusuke Nakamura Kazuaki Chayama 《PloS one》2013,8(12)
Hepatitis C virus (HCV) establishes a chronic infection in 70-80% of infected individuals. Many researchers have examined the effect of human leukocyte antigen (HLA) on viral persistence because of its critical role in the immune response against exposure to HCV, but almost all studies have proven to be inconclusive. To identify genetic risk factors for chronic HCV infection, we analyzed 458,207 single nucleotide polymorphisms (SNPs) in 481 chronic HCV patients and 2,963 controls in a Japanese cohort. Next, we performed a replication study with an independent panel of 4,358 cases and 1,114 controls. We further confirmed the association in 1,379 cases and 25,817 controls. In the GWAS phase, we found 17 SNPs that showed suggestive association (P < 1 × 10-5). After the first replication study, we found one intronic SNP in the HLA-DQ locus associated with chronic HCV infection, and when we combined the two studies, the association reached the level of genome-wide significance. In the second replication study, we again confirmed the association (P
combined = 3.59 × 10−16, odds ratio [OR] = 0.79). Subsequent analysis revealed another SNP, rs1130380, with a stronger association (OR=0.72). This nucleotide substitution causes an amino acid substitution (R55P) in the HLA-DQB1 protein specific to the DQB1*03 allele, which is common worldwide. In addition, we confirmed an association with the previously reported IFNL3-IFNL4 locus and propose that the effect of DQB1*03 on HCV persistence might be affected by the IFNL4 polymorphism. Our findings suggest that a common amino acid substitution in HLA-DQB1 affects susceptibility to chronic infection with HCV in the Japanese population and may not be independent of the IFNL4 genotype. 相似文献
69.
Seunghee Seo Kanako Takayama Kyosuke Uno Kazutaka Ohi Ryota Hashimoto Daisuke Nishizawa Kazutaka Ikeda Norio Ozaki Toshitaka Nabeshima Yoshiaki Miyamoto Atsumi Nitta 《PloS one》2013,8(10)
The single nucleotide polymorphism (SNP) rs13438494 in intron 24 of PCLO was significantly associated with bipolar disorder in a meta-analysis of genome-wide association studies. In this study, we performed functional minigene analysis and bioinformatics prediction of splicing regulatory sequences to characterize the deep intronic SNP rs13438494. We constructed minigenes with A and C alleles containing exon 24, intron 24, and exon 25 of PCLO to assess the genetic effect of rs13438494 on splicing. We found that the C allele of rs13438494 reduces the splicing efficiency of the PCLO minigene. In addition, prediction analysis of enhancer/silencer motifs using the Human Splice Finder web tool indicated that rs13438494 induces the abrogation or creation of such binding sites. Our results indicate that rs13438494 alters splicing efficiency by creating or disrupting a splicing motif, which functions by binding of splicing regulatory proteins, and may ultimately result in bipolar disorder in affected people. 相似文献
70.