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41.
The activities of casein kinases 1 and 2 in cytosol fractions prepared from 12 different rat tissues were compared. Casein kinase activities were detected in all tissues examined. Total casein kinase activities of lung, spleen, testis, and thymus were much higher than those of skeletal muscle, cardiac muscle, and adrenal gland. When activities of casein kinases 1 and 2 partially purified from lung, spleen, testis, and thymus prepared from 5 rats were compared, both total and specific activities of these kinases in testis were higher than those in the other tissues. These results indicate that testis is the most suitable tissue in rats for large-scale purification of casein kinase 1 as well as casein kinase 2. 相似文献
42.
Reiko Nishino Shohei Hamada Elghareeb E. Elboray Yoshihiro Ueda Takeo Kawabata Takumi Furuta 《Chirality》2020,32(5):588-593
Axial chirality in N,N-dimethylaminopyridines as well as N,N-dipropylaminopyridines bearing an internal carboxy group were evaluated based on their racemization barriers and circular dichroism spectra. The half-life of racemization of N,N-dipropylaminopyridine derivative 2 was estimated to be 19.7 days at 20°C. Its enantiomers isolated as optically active forms showed positive-negative and negative-positive Cotton effects for (+)- 2 and (−)- 2 , respectively, from 310 to 210 nm. Furthermore, (−)- 2 was applied as a chiral nucleophilic catalyst and exhibited asymmetric induction in acylative kinetic resolution of 1-(1-naphthyl)ethane-1-ol. 相似文献
43.
Minami Yoshiko; Takao Hiroyasu; Kanafuji Takeo; Miura Kazuo; Kondo Maki; Hara-Nishimura Ikuko; Nishimura Mikio; Matsubara Hiroshi 《Plant & cell physiology》1997,38(9):1069-1074
rß-Glucosidase of indigo plant (Polygonum tinctorium)has a high substrate specificity for indican (indoxyl rß-D-gIu-coside).To examine the localization of this rß-glucosidase,we fractionated the cells of the leaves and analysed them im-munocytochemically.Immunoelectron micrographs with specific antibodies againstthe rßglucosidase clearly showed that the rß-glucosidasewas localized in the stroma of the chloroplasts in mesophyllcells, but not in the thylakoid membrane. Chloroplasts wereisolated from the crude ho-mogenate of the fresh leaves by Percolldensity gradient centrifugation and then subjected to suborganellarfrac-tionation. rßGlucosidase activity was specificallydetected in the stromal fraction, but not in the thylakoid membrane.This was also supported by the result of an immunoblot of thefractions with anti-rßglucosidase antibodies. Therß-gIu-cosidase was immunocytochemically localizedin the chloroplasts of mesophyll cells, but not in any chloroplastsin marginal cells of the vascular bundle or epidermal cells;ribulose 1,5-bisphosphate carboxylase (Rubisco), a typical stromalprotein, was observed in all chloroplasts in these cells. Theseresults suggest that rß-glucosidase is tissue specificin its expression in the leaves of the indigo plant. (Received April 14, 1997; Accepted July 10, 1997) 相似文献
44.
Kenichi Takeo 《Carbohydrate research》1983,112(1):73-84
Selective tritylation of methyl β-sophoroside (1) and subsequent acetylation gave the 3,4,2′,3′,4′-penta-O-acetyl-6,6′-di-O-trityl derivative, which was O-detritylated, and the product p-toluenesulfonylated, to give methyl 3,4,2′,3′,4′-penta-O-acetyl-6,6′-di-O-p-tolylsulfonyl-β-sophoroside (4) in 63% net yield. Compound 4 was also obtained in 69% yield by p-toluenesulfonylation of 1, followed by acetylation. Several, 6,6′-disubstituted derivatives of 1 were synthesized by displacement reactions of 4 with various nucleophiles. Treatment of 4 with sodium methoxide afforded methyl 3,6:3′,6′-dianhydro-β-sophoroside. Several 6- and 6′-monosubstituted derivatives of 1 were prepared, starting from the 4,6-O-benzylidene derivative of 1. 相似文献
45.
Kakiuchi C Ishiwata M Nanko S Kunugi H Minabe Y Nakamura K Mori N Fujii K Umekage T Tochigi M Kohda K Sasaki T Yamada K Yoshikawa T Kato T 《Biochemical and biophysical research communications》2005,336(4):1136-1143
Altered endoplasmic reticulum stress (ER) response signaling is suggested in bipolar disorder. Previously, we preliminarily reported the genetic association of HSPA5 (GRP78/BiP) with bipolar disorder. Here, we extended our analysis by increasing the number of Japanese case-control samples and NIMH Genetics Initiative bipolar trio samples (NIMH trios), and also analyzed schizophrenia samples. In Japanese, nominally significant association of one haplotype was observed in extended samples of bipolar disorder but not in schizophrenia. In NIMH trios, no association was found in total samples. However, an exploratory analysis suggested that the other haplotype was significantly over-transmitted to probands only from the paternal side. The associated haplotype in Japanese or NIMH pedigrees shared three common polymorphisms in the promotor, which was found to alter promotor activity. These findings suggested promotor polymorphisms of HSPA5 may affect the interindividual variability of ER stress response and may confer a genetic risk factor for bipolar disorder. 相似文献
46.
Minoru Kawakami Masafumi Umeda Naomi Nakagata Toru Takeo Ken-ichi Yamamura 《BMC developmental biology》2011,11(1):1-17
Background
Heparan sulfate (HS) is present on the surface of virtually all mammalian cells and is a major component of the extracellular matrix (ECM), where it plays a pivotal role in cell-cell and cell-matrix cross-talk through its large interactome. Disruption of HS biosynthesis in mice results in neonatal death as a consequence of malformed lungs, indicating that HS is crucial for airway morphogenesis. Neonatal mortality (~50%) in newborns with congenital diaphragmatic hernia (CDH) is principally associated with lung hypoplasia and pulmonary hypertension. Given the importance of HS for lung morphogenesis, we investigated developmental changes in HS structure in normal and hypoplastic lungs using the nitrofen rat model of CDH and semi-synthetic bacteriophage ('phage) display antibodies, which identify distinct HS structures.Results
The pulmonary pattern of elaborated HS structures is developmentally regulated. For example, the HS4E4V epitope is highly expressed in sub-epithelial mesenchyme of E15.5 - E17.5 lungs and at a lower level in more distal mesenchyme. However, by E19.5, this epitope is expressed similarly throughout the lung mesenchyme. We also reveal abnormalities in HS fine structure and spatiotemporal distribution of HS epitopes in hypoplastic CDH lungs. These changes involve structures recognised by key growth factors, FGF2 and FGF9. For example, the EV3C3V epitope, which was abnormally distributed in the mesenchyme of hypoplastic lungs, is recognised by FGF2.Conclusions
The observed spatiotemporal changes in HS structure during normal lung development will likely reflect altered activities of many HS-binding proteins regulating lung morphogenesis. Abnormalities in HS structure and distribution in hypoplastic lungs can be expected to perturb HS:protein interactions, ECM microenvironments and crucial epithelial-mesenchyme communication, which may contribute to lung dysmorphogenesis. Indeed, a number of epitopes correlate with structures recognised by FGFs, suggesting a functional consequence of the observed changes in HS in these lungs. These results identify a novel, significant molecular defect in hypoplastic lungs and reveals HS as a potential contributor to hypoplastic lung development in CDH. Finally, these results afford the prospect that HS-mimetic therapeutics could repair defective signalling in hypoplastic lungs, improve lung growth, and reduce CDH mortality. 相似文献47.
Paired fins and associated internal structures of the epauletic sharkHemiscyllium ocellatum, were described on the basis of three specimens. A comparison with other genera showed the epaulette shark to be, characterized
by two elongated basal cartilages articulating with a distally projecting articular condyle on the coracoid, a loosely separated
radial series with an intermediate series, a levator pectoralis inferior muscle and an anterolaterally developed depressor
pectoralis muscle in the pectoral fin, and an elongated anterior pelvic basal cartilage articulating with a distally projecting
articular condyle and an anterolaterally developed depressor pelvicus muscle in the pelvic fin. In captivity, the sharks exhibited
both upright and crawling behavior on the bottom by using the pectoral and pelvic fins and bending the body. The distinctive
morphological characters are shared by otherHemiscyllium species and are suggested as important factors enabling their unique behavior associated with a complex coral reef habitat. 相似文献
48.
Yusuke Echigoya Hirotarou Okabe Takuya Itou Hideki Endo Takeo Sakai 《Molecular biology reports》2011,38(1):461-469
Muscle glycogen synthase (GYS1) is the rate-limiting enzyme in glycogen synthesis, and its activity is regulated by the phosphorylation
states of certain amino acid residues encoded by the GYS1 gene. In the present study, the authors molecularly characterized the full-length equine GYS1 (eGYS1) cDNA and found that
it contains a less common polyadenylation signal (AATACA). An amino acid alignment with other mammalian GYS1 showed that the
phosphorylation sites in eGYS1 are completely conserved. Genomic DNA analysis revealed that the equine-specific substitutions
(Glu 16 Asp and Ala 252 Thr) were completely conserved among six equine species. The tissue expression profiles of eGYS1,
equine type II hexokinase (eHKII) and muscle-type phosphofructokinase (ePFKM) were determined by real-time PCR and western
blot analysis. The mRNA expression level of eGYS1 was significantly higher in the cervical muscle as compared to other tissues.
The cervical muscle and heart tissue samples contained a broad range of eGYS1 protein bands that appeared to reflect multiple
phosphorylation states. eHKII was predominately expressed only in the cervical muscle; unlike its expression in other mammals,
eHKII was not substantially expressed in the insulin-responsive heart or adipose tissue of horse. The expression level of
ePFKM mRNA was significantly higher in the heart than in the cervical muscle, which differs from the PFKM expression pattern
of other mammals. These tissue expression profiles are fundamental for the understanding of equine glucose metabolism. 相似文献
49.
50.
Rolling circle amplification (RCA) generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same. 相似文献