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1.
A.S.R. Donald Cecilia P.C. Soh Winifred M. Watkins W.T.J. Morgan 《Biochemical and biophysical research communications》1982,104(1):58-65
Human Sda-active Tamm-Horsfall urinary glycoprotein labelled with galactose oxidase and tritiated sodium borohydride was found to contain both galactose and N-acetylgalactosamine as [3H]-labelled terminal non-reducing sugars. Fragmentation of the macromolecule achieved by hydrazinolysis and acid hydrolysis was followed by fractionation of the degradation products by gel filtration, ion exchange and paper chromatography. A major product was a disaccharide which contained unlabelled galactose and [3H]-labelled N-acetylgalactosamine. Sugar analysis, sodium borohydride reduction, methylation analysis and enzymic degradation enabled the structure N-acetyl-D-galactosaminyl-β-(1→4)-D-galactose to be assigned to the disaccharide. 相似文献
2.
Toshiro Samejima Yoshihiko Soh Toshimasa Yano 《Bioscience, biotechnology, and biochemistry》2013,77(12):2285-2290
The equilibrium moisture contents of sun-cured (Kroumougrad), flue-cured (Bright Yellow—4) and air-cured (Burley-21 and Matsukawa) tobaccos were measured over a relative humidity range from 5 to 80% at 20°C. The moisture sorption isotherms of tobaccos were of sigmoid type, and classified into two groups. In a lower humidity range below ca. 40% RH, the A group (Kroumougrad and BY-4) had a smaller moisture sorption capacity than B group (Burley-21 and Matsukawa), while in a higher humidity range above ca. 50% RH the former had a larger moisture sorption capacity than the latter. By extracting with water, the moisture content of BY-4 was increased in the lower humidity range, while it decreased in the higher humidity range. However, the moisture content of Matsukawa was scarecely changed by extracting it with water. These results suggest that the differences in equilibrium moisture content with the type of curing were due to the differences in contents of water soluble com- ponents. To control the hygroscopic properties of a tobacco, therefore, the influences of the addition of sucrose and glycerol on the equilibrium moisture content were quantitatively analysed. The moisture sorption capacity of tobacco was greatly different from its nitrogen sorption capacity. The specific surface area of tobacco calculated from moisture sorption isotherm was ca. 110 times larger than the specific surface area calculated from the nitrogen sorption isotherm. Both the nitrogen and moisture sorption data should be necessary for better understanding of the complicated sorption-desorption phenomena in tobaccos. 相似文献
3.
O Takács I Sohár T Szilágyi F Guba 《Acta biologica Academiae Scientiarum Hungaricae》1977,28(2):221-230
The changes in the sarcoplasmic proteins of the m. gastrocnemius and m. soleus were examined by biochemical methods on the 5th, 7th, 14th and 28th days after plaster cast immobilization of the right hind limbs of adult rabbits. During 4 weeks the soluble/myofibrillar protein ratio increased from 0.47 to 0.75 in the m. gastrocnemius, and to 0.85 in the m. soleus. Evaluation of the relative quantities of the components identified after gel-electrophoresis separation led to the following results: (1) There was no, or no appreciable change in the glyceraldehyde-3-phosphate dehydrogenase, creatine kinase and enolase activities. (2) The enzymes lactate dehydrogenase, aldolase and the glycogenolytic enzymes showed a relative decrease in both muscles. (3) Phosphoglycerate kinase, phosphoglucose isomerase and pyruvate kinase increased in both muscles. (4) Changes of opposite directions were exhibited by myoglobin, myokinase and F-protein. These results provide new data on the biochemical characterization of these functionally different muscles, and on the mechanism of disuse atrophy. 相似文献
4.
Hiroki Otani Hiromasa Yamamoto Munenori Takaoka Masakiyo Sakaguchi Junichi Soh Masaru Jida Tsuyoshi Ueno Takafumi Kubo Hiroaki Asano Kazunori Tsukuda Katsuyuki Kiura Shinji Hatakeyama Eiji Kawahara Yoshio Naomoto Shinichiro Miyoshi Shinichi Toyooka 《PloS one》2015,10(6)
TAE226, a bis-anilino pyrimidine compound, has been developed as an inhibitor of focal adhesion kinase (FAK) and insulin-like growth factor-I receptor (IGF-IR). In this study, we investigated the effect of TAE226 on non-small-cell lung cancer (NSCLC), especially focusing on the EGFR mutational status. TAE226 was more effective against cells with mutant EGFR, including the T790M mutant, than against cells with wild-type one. TAE226 preferentially inhibited phospho-EGFR and its downstream signaling mediators in the cells with mutant EGFR than in those with wild-type one. Phosphorylation of FAK and IGF-IR was not inhibited at the concentration at which the proliferation of EGFR-mutant cells was inhibited. Results of the in vitro binding assay indicated significant differences in the affinity for TAE226 between the wild-type and L858R (or delE746_A750) mutant, and the reduced affinity of ATP to the L858R (or delE746_A750) mutant resulted in good responsiveness of the L858R (or delE746_A750) mutant cells to TAE226. Of interest, the L858R/T790M or delE746_A750/T790M mutant enhanced the binding affinity for TAE226 compared with the L858R or delE746_A750 mutant, resulting in the effectiveness of TAE226 against T790M mutant cells despite the T790M mutation restoring the ATP affinity for the mutant EGFR close to that for the wild-type. TAE226 also showed higher affinity of about 15-fold for the L858R/T790M mutant than for the wild-type one by kinetic interaction analysis. The anti-tumor effect against EGFR-mutant tumors including T790M mutation was confirmed in mouse models without any significant toxicity. In summary, we showed that TAE226 inhibited the activation of mutant EGFR and exhibited anti-proliferative activity against NSCLCs carrying EGFR mutations, including T790M mutation. 相似文献
5.
Michelle C. W. Tang Shelley A. Jacobs Deidre M. Mattiske Yu May Soh Alison N. Graham An Tran Shu Ly Lim Damien F. Hudson Paul Kalitsis Moira K. O’Bryan Lee H. Wong Jeffrey R. Mann 《PLoS genetics》2015,11(2)
Histones package DNA and regulate epigenetic states. For the latter, probably the most important histone is H3. Mammals have three near-identical H3 isoforms: canonical H3.1 and H3.2, and the replication-independent variant H3.3. This variant can accumulate in slowly dividing somatic cells, replacing canonical H3. Some replication-independent histones, through their ability to incorporate outside S-phase, are functionally important in the very slowly dividing mammalian germ line. Much remains to be learned of H3.3 functions in germ cell development.Histone H3.3 presents a unique genetic paradigm in that two conventional intron-containing genes encode the identical protein. Here, we present a comprehensive analysis of the developmental effects of null mutations in each of these genes. H3f3a mutants were viable to adulthood. Females were fertile, while males were subfertile with dysmorphic spermatozoa. H3f3b mutants were growth-deficient, dying at birth. H3f3b heterozygotes were also growth-deficient, with males being sterile because of arrest of round spermatids. This sterility was not accompanied by abnormalities in sex chromosome inactivation in meiosis I. Conditional ablation of H3f3b at the beginning of folliculogenesis resulted in zygote cleavage failure, establishing H3f3b as a maternal-effect gene, and revealing a requirement for H3.3 in the first mitosis. Simultaneous ablation of H3f3a and H3f3b in folliculogenesis resulted in early primary oocyte death, demonstrating a crucial role for H3.3 in oogenesis.These findings reveal a heavy reliance on H3.3 for growth, gametogenesis, and fertilization, identifying developmental processes that are particularly susceptible to H3.3 deficiency. They also reveal partial redundancy in function of H3f3a and H3f3b, with the latter gene being generally the most important. 相似文献
6.
Y. Q. Shirleen Soh Jan Philipp Junker Mark E. Gill Jacob L. Mueller Alexander van Oudenaarden David C. Page 《PLoS genetics》2015,11(9)
The chromosomal program of meiotic prophase, comprising events such as laying down of meiotic cohesins, synapsis between homologs, and homologous recombination, must be preceded and enabled by the regulated induction of meiotic prophase genes. This gene regulatory program is poorly understood, particularly in organisms with a segregated germline. We characterized the gene regulatory program of meiotic prophase as it occurs in the mouse fetal ovary. By profiling gene expression in the mouse fetal ovary in mutants with whole tissue and single-cell techniques, we identified 104 genes expressed specifically in pre-meiotic to pachytene germ cells. We characterized the regulation of these genes by 1) retinoic acid (RA), which induces meiosis, 2) Dazl, which is required for germ cell competence to respond to RA, and 3) Stra8, a downstream target of RA required for the chromosomal program of meiotic prophase. Initial induction of practically all identified meiotic prophase genes requires Dazl. In the presence of Dazl, RA induces at least two pathways: one Stra8-independent, and one Stra8-dependent. Genes vary in their induction by Stra8, spanning fully Stra8-independent, partially Stra8-independent, and fully Stra8-dependent. Thus, Stra8 regulates the entirety of the chromosomal program but plays a more nuanced role in governing the gene expression program. We propose that Stra8-independent gene expression enables the stockpiling of selected meiotic structural proteins prior to the commencement of the chromosomal program. Unexpectedly, we discovered that Stra8 is required for prompt down-regulation of itself and Rec8. Germ cells that have expressed and down-regulated Stra8 are refractory to further Stra8 expression. Negative feedback of Stra8, and subsequent resistance to further Stra8 expression, may ensure a single, restricted pulse of Stra8 expression. Collectively, our findings reveal a gene regulatory logic by which germ cells prepare for the chromosomal program of meiotic prophase, and ensure that it is induced only once. 相似文献
7.
Yueh-Chiang Hu Peter K. Nicholls Y. Q. Shirleen Soh Joseph R. Daniele Jan Philipp Junker Alexander van Oudenaarden David C. Page 《PLoS genetics》2015,11(3)
In mouse embryos at mid-gestation, primordial germ cells (PGCs) undergo licensing to become gametogenesis-competent cells (GCCs), gaining the capacity for meiotic initiation and sexual differentiation. GCCs then initiate either oogenesis or spermatogenesis in response to gonadal cues. Germ cell licensing has been considered to be a cell-autonomous and gonad-independent event, based on observations that some PGCs, having migrated not to the gonad but to the adrenal gland, nonetheless enter meiosis in a time frame parallel to ovarian germ cells -- and do so regardless of the sex of the embryo. Here we test the hypothesis that germ cell licensing is cell-autonomous by examining the fate of PGCs in Gata4 conditional mutant (Gata4 cKO) mouse embryos. Gata4, which is expressed only in somatic cells, is known to be required for genital ridge initiation. PGCs in Gata4 cKO mutants migrated to the area where the genital ridge, the precursor of the gonad, would ordinarily be formed. However, these germ cells did not undergo licensing and instead retained characteristics of PGCs. Our results indicate that licensing is not purely cell-autonomous but is induced by the somatic genital ridge. 相似文献
8.
9.
The fruitless (fru) gene in Drosophila has been proposed to play a master regulator role in the formation of neural circuitries for male courtship behavior, which is typically considered to be an innate behavior composed of a fixed action pattern as generated by the central pattern generator. However, recent studies have shed light on experience-dependent changes and sensory-input-guided plasticity in courtship behavior. For example, enhanced male-male courtship, a fru mutant “hallmark,” disappears when fru-mutant males are raised in isolation. The fact that neural fru expression is induced by neural activities in the adult invites the supposition that Fru as a chromatin regulator mediates experience-dependent epigenetic modification, which underlies the neural and behavioral plasticity. 相似文献
10.
The application of the mutated acetolactate synthase gene from rice as the selectable marker gene in the production of transgenic soybeans 总被引:1,自引:0,他引:1
Makoto Tougou Noriko Yamagishi Noriyuki Furutani Koichiro Kaku Tsutomu Shimizu Yoshihito Takahata Jun-ichi Sakai Seiji Kanematsu Soh Hidaka 《Plant cell reports》2009,28(5):769-776
We investigated selective culturing conditions for the production of transgenic soybeans. In this culturing system, we used
the acetolactate synthase (ALS)-inhibiting herbicide-resistance gene derived from rice (Os-mALS gene) as a selectable marker gene instead of that derived from bacteria, which interfered with the cultivation and practical
usage of transgenic crops. T1 soybeans grown from one regenerated plant after selection of the ALS-targeting pyrimidinyl carboxy (PC) herbicide bispyribac-sodium
(BS) exhibited herbicide resistance, and the introduction and expression of the Os-mALS gene were confirmed by genetic analysis. The selective culturing system promoted by BS herbicide, in which the Os-mALS gene was used as a selectable marker, was proved to be applicable to the production of transgenic soybeans, despite the appearance
of escaped soybean plants that did not contain the Os-mALS transgene. 相似文献