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891.
Tatsuya Ueki Nobuaki Furuno Qiang Xu Yuya Nitta Kan Kanamori Hitoshi Michibata 《Biochimica et Biophysica Acta (BBA)/General Subjects》2009
Background
Several species of ascidians accumulate extremely high levels of vanadium ions in the vacuoles of their blood cells (vanadocytes). The vacuoles of vanadocytes also contain many protons and sulfate ions. To maintain the concentration of sulfate ions, an active transporter must exist in the blood cells, but no such transporter has been reported in vanadium-accumulating ascidians.Methods
We determined the concentration of vanadium and sulfate ions in the blood cells (except for the giant cells) of Ascidia sydneiensis samea. We cloned cDNA for an Slc13-type sulfate transporter, AsSUL1, expressed in the vanadocytes of A. sydneiensis samea. The synthetic mRNA of AsSUL1 was introduced into Xenopus oocytes, and its ability to transport sulfate ions was analyzed.Results
The concentrations of vanadium and sulfate ions in the blood cells (except for the giant cells) were 38 mM and 86 mM, respectively. The concentration of sulfate ions in the blood plasma was 25 mM. The transport activity of AsSUL1 was dependent on sodium ions, and its maximum velocity and apparent affinity were 2500 pmol/oocyte/h and 1.75 mM, respectively.General significance
This could account for active uptake of sulfate ions from blood plasma where sulfate concentration is 25 mM, as determined in this study. 相似文献892.
893.
Takashi Hattori Takashi Mine Nobukazu Komatsu Akira Yamada Kyogo Itoh Hitoshi Shiozaki Kiyotaka Okuno 《Cancer immunology, immunotherapy : CII》2009,58(11):1843-1852
To investigate the safety and immunological responses of personalized peptide vaccination in combination with oral administration
of UFT and UZEL for metastatic colorectal carcinoma (mCRC), fourteen patients were enrolled in the present study. Peptides
were determined based on the presence of peptide-specific cytotoxic T lymphocyte precursors and IgG in each patient. A maximum
of four peptides were subcutaneously administered weekly with UFT (300 mg/m2 day−1) and UZEL (75 mg/day) for 4 weeks, followed by 1 week of rest. This therapy was well-tolerated although there was a grade-3
skin reaction at the vaccination site in one patient. An increase in peptide-specific interferon-γ production or peptide-specific
IgG after the tenth vaccination was observed in nine of ten or eight of ten patients tested, respectively. IgG responses were
well correlated with overall survival (P = 0.0215). The safety and immunological responsiveness of the present therapy suggest that this combination would be of clinical
benefit for mCRC patients, and further trials are merited.
T. Hattori and T. Mine equally contributed to this work. 相似文献
894.
Zhipeng Wang Yuhei Nishimura Yasuhito Shimada Noriko Umemoto Minoru Hirano Liqing Zang Takehiko Oka Chikara Sakamoto Junya Kuroyanagi Toshio Tanaka 《Gene》2009
Beta adrenergic receptors (β-ARs) are members of the G-protein-coupled receptor superfamily and mediate various physiological processes in many species. The expression patterns and functions of β-ARs in zebrafish are, however, largely unknown. We have identified zebrafish β-AR orthologs, which we have designated as adrb1, adrb2a, adrb2b, adrb3a and adrb3b. adrb1 was found to be expressed in the heart and brain. Expression of adrb2a predominated in the brain and skin, whereas adrb2b was found to be highly expressed in muscle, pancreas and liver. Both adrb3a and adrb3b were exclusively expressed in blood. Knock-down of these β-ARs by morpholino oligonucleotides revealed a functional importance of adrb2a in pigmentation. Expression of atp5a1 and atp5b, genes that encode subunits of F1F0-ATPase, which is known to be involved in pigmentation, was significantly increased by knock-down of adrb2a. Our data suggest that adrb2a may regulate pigmentation, partly by modulating F1F0-ATPase. 相似文献
895.
Makoto Fujii Kye Sook Yi Myung Jong Kim Sang Hoon Ha Sung Ho Ryu Pann‐Ghill Suh Hitoshi Yagisawa 《Journal of cellular biochemistry》2009,108(3):638-650
Phosphorylation of phospholipase C‐δ1 (PLC‐δ1) in vitro and in vivo was investigated. Of the serine/threonine kinases tested, protein kinase C (PKC) phosphorylated the serine residue(s) of bacterially expressed PLC‐δ1 most potently. It was also demonstrated that PLC‐δ1 directly bound PKC‐α via its pleckstrin homology (PH) domain. Using deletion mutants of PLC‐δ1 and synthetic peptides, Ser35 in the PH domain was defined as the PKC mediated in vitro phosphorylation site of PLC‐δ1. In vitro phosphorylation of PLC‐δ1 by PKC stimulated [3H]PtdIns(4,5)P2 hydrolyzing activity and [3H]Ins(1,4,5)P3‐binding of the PLC‐δ1. On the other hand, endogenous PLC‐δ1 was constitutively phosphorylated and phosphoamino acid analysis revealed that major phosphorylation sites were threonine residues in quiescent cells. The phosphorylation level and the species of phosphoamino acid were not changed by various stimuli such as PMA, EGF, NGF, and forskolin. Using matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectrometry, we determined that Thr209 of PLC‐δ1 is one of the constitutively phosphorylated sites in quiescent cells. The PLC activity was potentiated when constitutively phosphorylated PLC‐δ1 was dephosphorylated by endogenous phosphatase(s) in vitro. Additionally, coexpression with PKC‐α reduced serine phosphorylation of PLC‐δ1 detected by an anti‐phosphoserine antibody and PLC‐δ1‐dependent basal production of inositol phosphates in NIH‐3T3 cells, suggesting PKC‐α activates phosphatase or inactivates another kinase involved in PLC‐δ1 serine phosphorylation to modulate the PLC‐δ1 activity in vivo. Taken together, these results suggest that PLC‐δ1 has multiple phosphorylation sites and phosphorylation status of PLC‐δ1 regulates its activity positively or negatively depends on the phosphorylation sites. J. Cell. Biochem. 108: 638–650, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
896.
897.
898.
Kondou Y Higuchi M Takahashi S Sakurai T Ichikawa T Kuroda H Yoshizumi T Tsumoto Y Horii Y Kawashima M Hasegawa Y Kuriyama T Matsui K Kusano M Albinsky D Takahashi H Nakamura Y Suzuki M Sakakibara H Kojima M Akiyama K Kurotani A Seki M Fujita M Enju A Yokotani N Saitou T Ashidate K Fujimoto N Ishikawa Y Mori Y Nanba R Takata K Uno K Sugano S Natsuki J Dubouzet JG Maeda S Ohtake M Mori M Oda K Takatsuji H Hirochika H Matsui M 《The Plant journal : for cell and molecular biology》2009,57(5):883-894
Ectopic gene expression, or the gain-of-function approach, has the advantage that once the function of a gene is known the gene can be transferred to many different plants by transformation. We previously reported a method, called FOX hunting, that involves ectopic expression of Arabidopsis full-length cDNAs in Arabidopsis to systematically generate gain-of-function mutants. This technology is most beneficial for generating a heterologous gene resource for analysis of useful plant gene functions. As an initial model we generated more than 23 000 independent Arabidopsis transgenic lines that expressed rice fl-cDNAs (Rice FOX Arabidopsis lines). The short generation time and rapid and efficient transformation frequency of Arabidopsis enabled the functions of the rice genes to be analyzed rapidly. We screened rice FOX Arabidopsis lines for alterations in morphology, photosynthesis, element accumulation, pigment accumulation, hormone profiles, secondary metabolites, pathogen resistance, salt tolerance, UV signaling, high light tolerance, and heat stress tolerance. Some of the mutant phenotypes displayed by rice FOX Arabidopsis lines resulted from the expression of rice genes that had no homologs in Arabidopsis . This result demonstrated that rice fl-cDNAs could be used to introduce new gene functions in Arabidopsis. Furthermore, these findings showed that rice gene function could be analyzed by employing Arabidopsis as a heterologous host. This technology provides a framework for the analysis of plant gene function in a heterologous host and of plant improvement by using heterologous gene resources. 相似文献
899.
Taiji Kawakatsu Graziana Taramino Jun-Ichi Itoh Justin Allen Yutaka Sato Soon-Kwan Hong Ryan Yule Nobuhiro Nagasawa Mikiko Kojima Makoto Kusaba Hitoshi Sakakibara Hajime Sakai Yasuo Nagato 《The Plant journal : for cell and molecular biology》2009,58(6):1028-1040
Most aerial parts of the plant body are products of the continuous activity of the shoot apical meristem (SAM). Leaves are the major component of the aerial plant body, and their temporal and spatial distribution mainly determines shoot architecture. Here we report the identification of the rice gene PLASTOCHRON3 ( PLA3 )/ GOLIATH ( GO ) that regulates various developmental processes including the rate of leaf initiation (the plastochron). PLA3 / GO encodes a glutamate carboxypeptidase, which is thought to catabolize small acidic peptides and produce small signaling molecules. pla3 exhibits similar phenotypes to pla1 and pla2 – a shortened plastochron, precocious leaf maturation and rachis branch-to-shoot conversion in the reproductive phase. However, in contrast to pla1 and pla2 , pla3 showed pleiotropic phenotypes including enlarged embryo, seed vivipary, defects in SAM maintenance and aberrant leaf morphology. Consistent with these pleiotropic phenotypes, PLA3 is expressed in the whole plant body, and is involved in plant hormone homeostasis. Double mutant analysis revealed that PLA1 , PLA2 and PLA3 are regulated independently but function redundantly. Our results suggest that PLA3 modulates various signaling pathways associated with a number of developmental processes. 相似文献
900.
A remediation agent containing a biosurfactant was prepared by spray drying the sterilized culture broth of Gordonia sp. strain JE-1058, and the agent was designated as JE1058BS. On subjection to the baffled flask test developed by the United States Environmental Protection Agency, JE1058BS showed a strong potential to be applied as an oil spill dispersant even in the absence of a solvent. It also proved to be an effective bioremediation agent for the remediation of oil spills at sea. The addition of JE1058BS to seawater stimulated the degradation of weathered crude oil (ANS 521) via the activity of the indigenous marine bacteria. Its addition also stimulated the removal of crude oil from the surface of contaminated sea sand. These results indicate that biosurfactant-containing JE1058BS has a strong potential to be applied as a remediation agent for the clean-up of oil spills at sea and on shorelines. 相似文献