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101.
Motoi Kanagawa Zhongpeng Lu Chiyomi Ito Chie Matsuda Katsuya Miyake Tatsushi Toda 《PloS one》2014,9(9)
Defects in dystroglycan glycosylation are associated with a group of muscular dystrophies, termed dystroglycanopathies, that include Fukuyama congenital muscular dystrophy (FCMD). It is widely believed that abnormal glycosylation of dystroglycan leads to disease-causing membrane fragility. We previously generated knock-in mice carrying a founder retrotransposal insertion in fukutin, the gene responsible for FCMD, but these mice did not develop muscular dystrophy, which hindered exploring therapeutic strategies. We hypothesized that dysferlin functions may contribute to muscle cell viability in the knock-in mice; however, pathological interactions between glycosylation abnormalities and dysferlin defects remain unexplored. To investigate contributions of dysferlin deficiency to the pathology of dystroglycanopathy, we have crossed dysferlin-deficient dysferlin
sjl/sjl mice to the fukutin-knock-in fukutin
Hp/− and Large-deficient Large
myd/myd mice, which are phenotypically distinct models of dystroglycanopathy. The fukutin
Hp/− mice do not show a dystrophic phenotype; however, (dysferlin
sjl/sjl: fukutin
Hp/−) mice showed a deteriorated phenotype compared with (dysferlin
sjl/sjl: fukutin
Hp/+) mice. These data indicate that the absence of functional dysferlin in the asymptomatic fukutin
Hp/− mice triggers disease manifestation and aggravates the dystrophic phenotype. A series of pathological analyses using double mutant mice for Large and dysferlin indicate that the protective effects of dysferlin appear diminished when the dystrophic pathology is severe and also may depend on the amount of dysferlin proteins. Together, our results show that dysferlin exerts protective effects on the fukutin
Hp/− FCMD mouse model, and the (dysferlin
sjl/sjl: fukutin
Hp/−) mice will be useful as a novel model for a recently proposed antisense oligonucleotide therapy for FCMD. 相似文献
102.
Katsuya Koike Masato Mori Yukishige Ito Yoshiaki Nakahara Tomoya Ogawa 《Glycoconjugate journal》1987,4(2):109-116
The first total synthesis of glycosphingolipids isolated from wheat flour has been achieved in a regio- and stereo-controlled manner.Abbreviations THF
tetrahydrofuran
- DMF
dimethylformamide
Part 53 in the series Synthetic Studies on Cell Surface Glycans 相似文献
103.
M Hayakawa T Hori S Shibamoto M Tsujimoto N Oku F Ito 《Archives of biochemistry and biophysics》1991,286(2):323-329
Human placental membranes exhibited high-affinity receptors for tumor necrosis factor (TNF) (Kd = 5.6 x 10(-10) M) with a density of 1.2-1.7 x 10(10) sites/mg protein. The receptors were solubilized from these membranes with 1% Nonidet P-40, and the solubilized receptor was adsorbed to Con A-Sepharose and wheat germ agglutinin agarose columns, indicating that the TNF receptor derived from human placenta contains carbohydrate chains recognized by these lectins. TNF binding activity was eluted from a column of Sephacryl S-300 as a single peak of Mr 300 kDa. The solubilized receptor was further purified by TNF-Sepharose prepared by coupling of TNF to tresyl-activated Sepharose 4B. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the purified sample resolved five major bands of Mr 90, 78, 41, 35, and 11 kDa, suggesting that these polypeptides constitute a multimeric complex with a molecular mass of 300 kDa, as observed in gel filtration study. Furthermore, the TNF-Sepharose-bound fraction demonstrated GTP gamma S binding and GTPase activity. Immunoblot analysis showed that the 41- and 35-kDa polypeptides were recognized by antisera against alpha subunits and beta subunit of GTP-binding proteins, respectively. These results suggest that the native TNF receptor couples to a guanine nucleotide-binding protein to form a large complex structure in human placental membranes. 相似文献
104.
105.
Osamu Yamada Shuichi Ishida Fumio Futatsuya Kensaku Ito Hiroshi Yamamoto Katsura Munakata 《Bioscience, biotechnology, and biochemistry》2013,77(6):1235-1240
The discovery that anisomycin showed plant growth-regulating activity led to the investigation of compounds having p-methoxyphenyl group; the p-anisole derivatives. 4-Methoxydiphenylmethanes and related compounds inhibited the growth of both shoots and roots in test plants. Growth-inhibitory activity in the series of 4-methoxydiphenylmethanes was lowered by an increase in the electron donating or withdrawing ability of the substituent and was parabolically dependent on the Hammett’s σ. Selective actions of these compounds in their growth inhibition are discussed based on correlations between their activities against barnyard grass and other test plants.Some 4-methoxydiphenylmethanes induced chlorosis, a disturbance in phototropism or geotropism, and root hypertrophy. 相似文献
106.
We have identified DNA fragments which bind specifically to the nuclear matrix in vitro, termed matrix association regions (MARs), in the first and fourth introns of rat alpha 2-macroglobulin gene. The MAR in the first intron is enriched with sequences closely related to the cleavage consensus of topoisomerase II, and contains the binding site of nuclear factor-alpha, a sequence-specific DNA binding protein reported previously. 相似文献
107.
Emi?Ito Hiroaki?Waki Kozo?Miseki Takashi?Shimada Taka-Aki?Sato Kazuaki?Kakehi Minoru?Suzuki Akemi?SuzukiEmail author 《Glycoconjugate journal》2013,30(9):881-888
Four types of neutral glycosphingolipids (LacCer, Gb3Cer, Gb4Cer, and IV3αGalNAc-Gb4Cer; 10 pmol each) were analyzed using high-performance liquid chromatography (HPLC)-electrospray ionization quadrupole ion trap time-of-flight (ESI-QIT-TOF) mass spectrometry (MS) with a repeated high-speed polarity and MSn switching system. This system can provide six types of mass spectra, including positive and negative ion MS, MS2, and MS3 spectra, within 1 s per cycle. Using HPLC with a normal-phase column, information on the molecular weights of major molecular species of four neutral glycosphingolipids was obtained by detecting [M+Na]+ in the positive ion mode mass spectra and [M?H]? in the negative ion mode mass spectra. Sequences of glycosphingolipid oligosaccharide were obtained in the negative ion MS2 spectra. In addition, information on the ceramide structures was clearly obtained in the negative ion MS3 mass spectra. GlcCer molecular species were analyzed by HPLC-ESI-QIT-TOF MS with a reversed-phase column using 1 pmole of GlcCer. The structures of the seven molecular species of GlcCer, namely, d18:1-C16:0, d18:1-C18:0, d18:1-C20:0, d18:1-C22:0, d18:1-C23:0, d18:1-C24:1, and d18:1-C24:0, were characterized using positive ion MS and negative ion MS, MS2, and MS3. The established HPLC-ESI-QIT-TOF MS with MSn switching and a normal phase column has been successfully applied to the structural characterization of LacCer and Gb4Cer in a crude mixture prepared from human erythrocytes. 相似文献
108.
109.
Kanji Hori Yoshiharu Shimada Chihiro Oiwa Keisuke Miyazawa Keiji Ito 《Journal of applied phycology》1993,5(2):219-223
Nine species of marine algae have been assessed for the presence of novel hemagglutinins not extractable with buffer, unless
the algal tissue was pretreated with Pronase. All species examined contained hemagglutinins, indicating the existence of a
novel group of hemagglutinins which differed from those reported previously in marine algae. 相似文献
110.
Gene structure and expression of the MboI restriction--modification system. 总被引:3,自引:1,他引:3 下载免费PDF全文
The genes from Moraxella bovis encoding the MboI restriction--modification system were cloned and expressed in Escherichia coli. Three open reading frames were found in the sequence containing the genes. These genes, which we named mboA, mboB, and mboC, had the same orientation in the genome. Genes mboA and mboC encoded MboI methyltransferases (named M.MboA and M.MboC) with 294 and 273 amino acid residues, respectively. The mboB gene coded for MboI restriction endonuclease (R.MboI) with 280 amino acid residues. Recombinant E.coli-MBOI, which contained the whole MboI system, overproduced R.MboI. R.MboI activity from E.coli-MBOI was 480-fold that of M.bovis. The amino acid sequences deduced from these genes were compared with those of other restriction--modification systems. The protein sequences of the MboI system had 38-49% homology with those of the DpnII system. 相似文献