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31.
Hiroshi Ashihara Atsushi Komamine Masami Shimokoriyama 《Journal of plant research》1974,87(2):121-131
Changes in activities of the glycolytic and pentose phosphate (PP) pathways in glucose catabolism in various parts of the
hypocotyls obtained from 4-day-old etiolatedPhaseolus mungo seedlings were investigated by measuring the inhibition rates of respiration by iodoacetate and malonate, and the release
of14CO2 from [1-14C]- and [6-14C]glucose. The relative activity of the PP pathway in glucose catabolism was higher in the immature part (Part I) and the
aged part (Part V) of the hypocotyls than in the intermediary one (Part III), while the activity of the glycolytic pathway
decreased with aging.
On a fresh weight basis, the enzyme activities of the glycolytic and PP pathways were higher in Part I than in Parts III and
V. On a protein content basis, however, activities of the enzymes of the PP pathway increased with aging and differentiation
of the hypocotyls whereas those of the glycolytic pathway decreased. Levels of nicotinamide adenine nucleotides were found
to be in the following order: Part I>Part III> Part V for NAD++NADH; Part I>Part V>Part III for NADP++NADPH. The stimulative effect of methylene blue on decreasing the C6/C1 ratio was greater in Part III than in Part I, and No effect was observed in Part V.
These data suggest that a decrease in the activity of the glycolytic pathway with aging and differentiation may be due to
the decreasing glycolytic enzyme activities and NAD(H) content. The higher activity of the PP pathway in the immature part
is attributable to larger amounts of NADP(H) and enzymes of the PP pathway. The greater contribution of the PP pathway to
glucose catabolism in the aged part than in the intermediary part seems to results from a more active turnover of NADP and
the relatively higher activity of the enzymes of the PP pathway than those of the glycolytic pathway. 相似文献
32.
Establishment of five human myeloma cell lines 总被引:3,自引:0,他引:3
Masayoshi Namba Takemi Ohtsuki Masaharu Mori Atsushi Togawa Hideho Wada Takashi Sugihara Yoshihito Yawata Tetsuo Kimoto 《In vitro cellular & developmental biology. Plant》1989,25(8):723-729
Summary Five human myeloma cell lines, KMM-1, KMS-5, KMS-11, KMS-12- PE, and KMS-12-BM, have been established at Kawasaki Medical
School since 1980. As the KMS-12-PE and KMS-12-BM lines were obtained from the same patient, these five cell lines have been
derived from four patients with multiple myeloma. The five myeloma cell lines are stably growing at present in RPMI 1640 medium
supplemented with 10% fetal bovine serum. They can also grow in a defined culture medium without serum. That these cell lines
were, human myeloma cells was confirmed by the following findings. Ultranstructually, all five cell lines showed features
characteristic of plasma cells. KMM-1 and KMS-11 cells secreted lambda and kappa chains into the culture medium, respectively,
but the other cell lines produced no immunoglobulins. KMM-1 expressed cytoplasmic lambda antigen, KMS-5 showed cytoplasmic
delta, and KMS-11 expressed surface kappa, whereas KMS-12-PE and KMS-12-BM cells showed no surface or cytoplasmic immunoglobulins.
Regarding reaction with a monoclonal plasma cell antibody (PCA-1), four of the five lines were positive, the exception being
KMS-5. Another monoclonal antibody (CD38), which also recognizes plasma cells, reponded to KMM-1, KMS-12-PE, and KSM-12-BM.
KMS-5 cells expressed acute lymphoblastic leukemia antigens (CALLA). These data suggest that such lines as KMM-1, KMS-11,
KMS-12-PE, and KMS-12-BM represent later stages of B-cell differentiation, and that KMS-5 represents a relatively early stage
of B-cell differentiation. All the cell lines lacked Epstein-Barr virus nuclear antigen, showed abnormal karyotypes of human
origin, and differed from each other in the isozyme patterns examined. Only KMS-5 was tumorigenic when transplanted subcutaneously
into nude mice. 相似文献
33.
Membrane Viscosity Correlates with α1 -Adrenergic Signal Transduction of the Aged Rat Cerebral Cortex
Atsushi Miyamoto Tsunehisa Araiso Tomiyasu Koyama Hideyo Ohshika 《Journal of neurochemistry》1990,55(1):70-75
We investigated, using adult (2-month-old) and senescent (12- and 24-month-old) rats, the effects of aging on the relationship between the alpha 1-adrenergic coupling system and the membrane viscosity of the cerebral cortex. There was no age-related difference in the KD values of [3H]prazosin binding on the membranes. The Bmax values of [3H]prazosin binding were reduced with advanced age. Norepinephrine-induced formation of 3H-labeled inositol phosphates (3H-IPs) in the slices increased with advanced age. The EC50 values for norepinephrine to stimulate the formation of 3H-IPs at advanced age were lower than that at adult age. The cholesterol content in membranes increased with advanced age. No changes in the phospholipid content in membranes were observed with advanced age. Concomitantly, an increase of the molar ratio of cholesterol to phospholipids was observed with advanced age. The membrane viscosity as measured by 1,6-diphenyl-1,3,5-hexatriene increased with advanced age. These results indicate that the altered cholesterol content and/or viscosity in cortical membranes of the aged rat may account for the loss of alpha 1-adrenergic receptor density and/or compensatory changes in the receptor-phospholipase C coupling system. 相似文献
34.
Isolation of Glutamyltaurine from Bovine Brains and Proof of Its γ-Linkage by the B/E Linked Scan SIMS Technique 总被引:1,自引:1,他引:0
Ko Nakamura Kunihiko Higashiura Naoharu Nishimura Atsushi Yamamoto Ikuo Tooyama Hiroshi Kimura Kazuharu Ienaga 《Journal of neurochemistry》1990,55(3):1064-1066
We isolated a glutamyltaurine from bovine brains and determined its structure as gamma-glutamyltaurine (gamma-Glu-Tau; glutaurine) by use of a new mass spectrometric technique [B/E linked scan sputtered ion mass spectrometry (SIMS)], which we have recently shown to be useful for distinguishing the gamma- from the alpha-isomer of glutamyl-dipeptides. Neither the alpha-isomer of glutamyltaurine nor any aspartyltaurines could be detected in bovine brain. 相似文献
35.
36.
Naoto Ohnishi Hiroaki Kodania Satoshi Ando Atsushi Komamine 《Physiologia plantarum》1990,80(1):95-101
The effects of inhibition of the synthesis of protein, mRNA or rRNA on the progression of the cell cycle have been analyzed in cultures of Catharanthus roseus in which cells were induced to divide in synchrony by the double phosphate starvation method. The partial inhibition of protein synthesis at the G1 phase by anisoniycio or cycloheximide caused the arrest of cells in the G1 phase or delayed the entry of cells into the S phase. When protein synthesis was partially inhibited at the S phase, cell division occurred to about the same extent as in the control. When asynchronously dividing cells were treated with cycloheximide, cells accumulated in the G1 phase, as shown by flow-cytometric analysis. The partial inhibition of mRNA synthesis by α-amanitin at the G1 phase caused the arrest of cells in the G1 phase, although partial inhibition of mRNA synthesis at the S phase had little effect on cell division. In the case of inhibition of synthesis of rRNA by actinomycin D at the G1 phase, initiation of DNA synthesis was observed, but no subsequent DNA synthesis or the division of cells occurred. However, the addition of actinomycin D during the S phase had no effect on cell division. These results suggest that specific protein(s), required for the progression of the cell cycle, are synthesized in the G1 phase, and that the mRNA(s) that encode these proteins are also synthesized at the G1 phase. 相似文献
37.
38.
Evidence that Glyceraldehyde-3-Phosphate Dehydrogenase Is Involved in Age-Induced Apoptosis in Mature Cerebellar Neurons in Culture 总被引:5,自引:0,他引:5
Ryoichi Ishitani Katsuyoshi Sunaga Atsushi Hirano †Paul Saunders Nobuo Katsube †De-Maw Chuang 《Journal of neurochemistry》1996,66(3):928-935
Abstract: Under typical culture conditions, cerebellar granule cells die abruptly after 17 days in vitro. This burst of neuronal death involves ultrastructural changes and internucleosomal DNA fragmentations characteristic of apoptosis and is effectively arrested by pretreatment with actinomycin-D and cycloheximide. The level of a 38-kDa protein in the particulate fraction is markedly increased during age-induced cell death and by pretreatment with NMDA, which potentiates this cell death. Conversely, the age-induced increment of the 38-kDa particulate protein is suppressed by actinomycin-D and cycloheximide. N-terminal microsequencing of the 38-kDa protein revealed sequence identity with glyceraldehyde-3-phosphate dehydrogenase (GAPDH). A GAPDH antisense oligodeoxyribonucleotide blocks age-induced expression of the particulate 38-kDa protein and effectively inhibits neuronal apoptosis. In contrast, the corresponding sense oligonucleotide of GAPDH was completely ineffective in preventing the age-induced neuronal death and the 38-kDa protein overexpression. Moreover, the age-induced expression of the 38-kDa protein is preceded by a pronounced increase in the GAPDH mRNA level, which is abolished by actinomycin-D, cycloheximide, or the GAPDH antisense, but not sense, oligonucleotide. Thus, our results suggest that overexpression of GAPDH in the particulate fraction has a direct role in age-induced apoptosis of cerebellar neurons. 相似文献
39.
Cloning and nucleotide sequence of the mono- and diacylglycerol lipase gene (mdlB) of Aspergillus oryzae 总被引:1,自引:0,他引:1
Atsushi Tsuchiya Hidekazu Nakazawa Jinichi Toida Kunio Ohnishi Junichi Sekiguchi 《FEMS microbiology letters》1996,143(1):63-67
Abstract Aspergillus oryzae IFO4202 produces at least two extracellular lipolytic enzymes L1 and L2 (cutinase, and mono- and diacylglycerol lipase, respectively). Southern hybridization of restriction enzyme-digested genomic DNA fragments with 23mer oligonucleotides synthesized according to the amino acid sequence of the L2 as probe suggested the presence of the L2 gene (tentatively designated as mdlB ) and an additional weakly hybridizing region. A fragment containing the genomic mdlB gene was cloned in Escherichia coli . Nucleotide sequencing of the fragment revealed an open reading frame, comprising 1021 nucleotides, which contains two introns (51 and 52 nucleotides). Putative polyadenylation signals were found 182 and 287 bp downstream of the stop codon. The deduced amino acid sequence of the mdlB gene corresponds to 306 amino acid residues including a leader sequence of 28 amino acids and is highly similar to that of the mdlA gene of Penicillium camembertii . Three residues presumed to form the catalytic triad (serine, aspartic acid and histidine) of lipases were also conserved. 相似文献
40.