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121.
Joho Masanori; Sukenobu Yuriko; Egashira Eiji; Murayama Tetsuo 《Plant & cell physiology》1983,24(3):389-394
The sensitivity of twelve strains of Saccharomyces cerevisiaeto Cd2+ was examined in correlation with the uptake of Cd2+.Strains of S. cerevisiae were grouped into three categoriesdepending on the sensitivity of cells grown on agar-plates containingvarious concentrations of Cd2+. 1) The sensitive group did notgrow in 0.1 mM Cd2+. 2) The sub-tolerant group was capable ofgrowth at 0.3 min Cd2+, but not at 0.4 mM Cd2+. 3) The tolerantgroup was capable of growth at 0.4 mM Cd2+ or higher. In thesestrain groups the increase in sensitivity to Cd2+ was associatedwith an increase in the activity of Cd2+ absorption.
1 This study is dedicated to the late president J. Ashida ofEhime University. (Received November 25, 1982; Accepted February 14, 1983) 相似文献
122.
Yasuhisa Nogi Hideo Shimada Yuriko Matsuzaki Hideaki Hashimoto Toshio Fukasawa 《Molecular & general genetics : MGG》1984,195(1-2):29-34
Summary The galactose analogue 2-deoxygalactose was found to inhibit the growth of a mutant strain of Saccharomyces cerevisiae constitutively producing the set of galactose utilization enzymes. Based on this fact, the yeast GAL80 gene negatively regulating the expression of the genes encoding those enzymes was isolated for its ability to confer 2-deoxygalactose resistance on a strain carrying a recessive mutation in that gene. The GAL80 gene was located within a 3.0 kb fragment in the cloned DNA. When the isolated gene was incorporated into a multi-copy plasmid, the induced level of three enzymes encoded by the gene cluster GAL7-GAL10-GAL1 in the host chromosome was lowered. Such a gene dosage effect of GAL80 was further pronounced if sucrose, a sugar causing catabolite repression, was added to the growth medium. The ratio of the enzyme activity of the yeast bearing multiple copies of GAL80 to that of the yeast bearing its single copy significantly varied with the enzyme. From these results we suggest that the intracellular inducer interacts with the GAL80 product and that GAL80 molecules directly bind the GAL cluster genes with an affinity different from one gene to another.The first article of this series is in Mol Gen Genet 191:31–38On a leave absence from Nikka Whisky Co. 相似文献
123.
Yuri Takeda Shiro Suzuki Yuki Tobimatsu Keishi Osakabe Yuriko Osakabe Safendrri K. Ragamustari Masahiro Sakamoto Toshiaki Umezawa 《The Plant journal : for cell and molecular biology》2019,97(3):543-554
The aromatic composition of lignin is an important trait that greatly affects the usability of lignocellulosic biomass. We previously identified a rice (Oryza sativa) gene encoding coniferaldehyde 5‐hydroxylase (OsCAld5H1), which was effective in modulating syringyl (S)/guaiacyl (G) lignin composition ratio in rice, a model grass species. Previously characterized OsCAld5H1‐knockdown rice lines, which were produced via an RNA‐interference approach, showed augmented G lignin units yet contained considerable amounts of residual S lignin units. In this study, to further investigate the effect of suppression of OsCAld5H1 on rice lignin structure, we generated loss‐of‐function mutants of OsCAld5H1 using the CRISPR/Cas9‐mediated genome editing system. Homozygous OsCAld5H1‐knockout lines harboring anticipated frame‐shift mutations in OsCAld5H1 were successfully obtained. A series of wet‐chemical and two‐dimensional NMR analyses on cell walls demonstrated that although lignins in the mutant were predictably enriched in G units all the tested mutant lines produced considerable numbers of S units. Intriguingly, lignin γ‐p‐coumaroylation analysis by the derivatization followed by reductive cleavage method revealed that enrichment of G units in lignins of the mutants was limited to the non‐γ‐p‐coumaroylated units, whereas grass‐specific γ‐p‐coumaroylated lignin units were almost unaffected. Gene expression analysis indicated that no homologous genes of OsCAld5H1 were overexpressed in the mutants. These data suggested that CAld5H is mainly involved in the production of non‐γ‐p‐coumaroylated S lignin units, common in both eudicots and grasses, but not in the production of grass‐specific γ‐p‐coumaroylated S units in rice. 相似文献
124.
Horie Y Ito Y Ono M Moriwaki N Kato H Hamakubo Y Amano T Wachi M Shirai M Asayama M 《Molecular genetics and genomics : MGG》2007,278(3):331-346
Light-responsive gene expression is crucial to photosynthesizing organisms. Here, we studied functions of cis-elements (AU-box and SD sequences) and a trans-acting factor (ribonuclease, RNase) in light-responsive expression in cyanobacteria. The results indicated that AU-rich nucleotides
with an AU-box, UAAAUAAA, just upstream from an SD confer instability on the mRNA under darkness. An RNase E/G homologue,
Slr1129, of the cyanobacterium Synechocystis sp. strain PCC 6803 was purified and confirmed capable of endoribonucleolytic cleavage at the AU- (or AG)-rich sequences
in vitro. The cleavage depends on the primary target sequence and secondary structure of the mRNA. Complementation tests using
Escherichia coli rne/rng mutants showed that Slr1129 fulfilled the functions of both the RNase E and RNase G. An analysis of systematic mutations
in the AU-box and SD sequences showed that the cis-elements also affect significantly mRNA stability in light-responsive genes. These results strongly suggested that dark-induced
mRNA instability involves RNase E/G-type cleavage at the AU-box and SD sequences in cyanobacteria. The mechanical impact and
a possible common mechanism with RNases for light-responsive gene expression are discussed.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
125.
126.
Maruyama T Kusakari S Sato-Hashimoto M Hayashi Y Kotani T Murata Y Okazawa H Oldenborg PA Kishi S Matozaki T Ohnishi H 《Journal of neurochemistry》2012,121(6):891-902
Signal regulatory protein α (SIRPα) is a neuronal membrane protein that undergoes tyrosine phosphorylation in the brain of mice in response to forced swim (FS) stress in cold water, and this response is implicated in regulation of depression-like behavior in the FS test. We now show that subjection of mice to the FS in warm (37 °C) water does not induce the tyrosine phosphorylation of SIRPα in the brain. The rectal temperature (T(rec) ) of mice was reduced to 27° to 30 °C by performance of the FS for 10 min in cold water, whereas it was not affected by the same treatment in warm water. The level of tyrosine phosphorylation of SIRPα in the brain was increased by administration of ethanol or picrotoxin, starvation, or cooling after anesthesia, all of which also induced hypothermia. Furthermore, the tyrosine phosphorylation of SIRPα in cultured hippocampal neurons was induced by lowering the temperature of the culture medium. CD47, a ligand of SIRPα, as well as Src family kinases or SH2 domain-containing protein phosphatase 2 (Shp2), might be important for the basal and the hypothermia-induced tyrosine phosphorylation of SIRPα. Hypothermia is therefore likely an important determinant of both the behavioral immobility and tyrosine phosphorylation of SIRPα observed in the FS test. 相似文献
127.
Takeuchi K Nagata N Kato SI Ami Y Suzaki Y Suzuki T Sato Y Tsunetsugu-Yokota Y Mori K Van Nguyen N Kimura H Nagata K 《Journal of virology》2012,86(6):3027-3037
A major difference between vaccine and wild-type strains of measles virus (MV) in vitro is the wider cell specificity of vaccine strains, resulting from the receptor usage of the hemagglutinin (H) protein. Wild-type H proteins recognize the signaling lymphocyte activation molecule (SLAM) (CD150), which is expressed on certain cells of the immune system, whereas vaccine H proteins recognize CD46, which is ubiquitously expressed on all nucleated human and monkey cells, in addition to SLAM. To examine the effect of the H protein on the tropism and attenuation of MV, we generated enhanced green fluorescent protein (EGFP)-expressing recombinant wild-type MV strains bearing the Edmonston vaccine H protein (MV-EdH) and compared them to EGFP-expressing wild-type MV strains. In vitro, MV-EdH replicated in SLAM(+) as well as CD46(+) cells, including primary cell cultures from cynomolgus monkey tissues, whereas the wild-type MV replicated only in SLAM(+) cells. However, in macaques, both wild-type MV and MV-EdH strains infected lymphoid and respiratory organs, and widespread infection of MV-EdH was not observed. Flow cytometric analysis indicated that SLAM(+) lymphocyte cells were infected preferentially with both strains. Interestingly, EGFP expression of MV-EdH in tissues and lymphocytes was significantly weaker than that of the wild-type MV. Taken together, these results indicate that the CD46-binding activity of the vaccine H protein is important for determining the cell specificity of MV in vitro but not the tropism in vivo. They also suggest that the vaccine H protein attenuates MV growth in vivo. 相似文献
128.
129.
130.
Shinobu Kitazume Akiomi Yoshihisa Takayoshi Yamaki Masayoshi Oikawa Yuriko Tachida Kazuko Ogawa Rie Imamaki Yoshiaki Hagiwara Noriaki Kinoshita Yasuchika Takeishi Katsutoshi Furukawa Naoki Tomita Hiroyuki Arai Nobuhisa Iwata Takaomi Saido Naomasa Yamamoto Naoyuki Taniguchi 《The Journal of biological chemistry》2012,287(48):40817-40825
Most Alzheimer disease (AD) patients show deposition of amyloid β (Aβ) peptide in blood vessels as well as the brain parenchyma. We previously found that vascular endothelial cells express amyloid β precursor protein (APP) 770, a different APP isoform from neuronal APP695, and produce Aβ. Since the soluble APP cleavage product, sAPP, is considered to be a possible marker for AD diagnosis, sAPP has been widely measured as a mixture of these variants. We hypothesized that measurement of the endothelial APP770 cleavage product in patients separately from that of neuronal APP695 would enable discrimination between endothelial and neurological dysfunctions. Using our newly developed ELISA system for sAPP770, we observed that inflammatory cytokines significantly enhanced sAPP770 secretion by endothelial cells. Furthermore, we unexpectedly found that sAPP770 was rapidly released from activated platelets. We also found that cerebrospinal fluid mainly contained sAPP695, while serum mostly contained sAPP770. Finally, to test our hypothesis that sAPP770 could be an indicator for endothelial dysfunction, we applied our APP770 ELISA to patients with acute coronary syndrome (ACS), in which endothelial injury and platelet activation lead to fibrous plaque disruption and thrombus formation. Development of a biomarker is essential to facilitate ACS diagnosis in clinical practice. The results revealed that ACS patients had significantly higher plasma sAPP770 levels. Furthermore, in myocardial infarction model rats, an increase in plasma sAPP preceded the release of cardiac enzymes, currently used markers for acute myocardial infarction. These findings raise the possibility that sAPP770 can be a useful biomarker for ACS. 相似文献