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51.
Parathyroid hormone-related protein is a possible autocrine growth inhibitor for lymphocytes 总被引:6,自引:0,他引:6
N Adachi K Yamaguchi Y Miyake S Honda K Nagasaki Y Akiyama I Adachi K Abe 《Biochemical and biophysical research communications》1990,166(3):1088-1094
Adult T-cell leukemia (ATL)-related cells have the ability to produce a newly-isolated calcium-regulating protein, parathyroid hormone-related protein (PTHrP). The present study revealed that lectin-stimulated normal lymphocytes produce immunoreactive (IR)-PTHrP. When the T-cell-enriched fraction was purified from normal lymphocytes and then treated with lectin, a similar amount of IR-PTHrP was detected, suggesting that IR-PTHrP is an actual product of T-lymphocytes. A biologically active fragment of PTHrP, PTHrP(1-34), suppressed DNA synthesis in lectin-stimulated lymphocytes at concentrations greater than 50 pg/mL; the same concentration range of IR-PTHrP detected in the cultured media of lectin-stimulated lymphocytes. Therefore, it is reasonable to postulate that PTHrP is a cytokine inhibiting the cellular growth of normal lymphocytes. 相似文献
52.
Katsuhiko Hidaka Shin-Ichi Akiyama Michihiko Kuwano 《Journal of cellular physiology》1981,106(1):41-47
Previous studies from our laboratory have shown that Chinese hamster V79 cells mutated to high level resistance to amphotericin B have a lower cellular level of cholesterol, the target molecule for the polyene antibiotic. Two amphotericin B-resistant (AMBR) mutants were each hybridized to their parental amphotericin B-sensitive (AMBS) V79 cells. All the hybrids derived from AMBR/AMBS fusions were as sensitive to polyene antibiotics (amphotericin B, filipin, and pimaricin) as AMBS/AMBS hybrids. The AMBR/AMBS hybrids were found to contain cholesterol per phospholipids that is comparable to those in AMBS or AMBS/AMBS. The analysis of hybrids formed between mutant and wild-type cells thus indicated that resistance to amphotericin B is a recessive marker, and that the cellular level of cholesterol is compensated in the AMBS/AMBR hybrids. Hybrids of AMBR and AMBR cells were all resistant, so that the three AMBR mutants all fell into a single complementation group. 相似文献
53.
Y Nagai K Akiyama S Kotani Y Watanabe T Shimono T Shiba S Kusumoto 《Cellular immunology》1978,35(1):168-172
The peptide N-acetylmuramyl-l-alanyl-d-isoglutamine (MDP), which has adjuvant activities, and 17 of its derivatives and analogs were synthesized and assayed to elucidate the structure necessary for adjuvant activity in induction of experimental allergic encephalomyelitis (EAE) in guinea pigs. The results revealed the importance of the d configuration and the α-carboxamide group of the isoglutaminyl residue of MDP for adjuvant activity. Replacement of the l-alanyl residue of MDP by d-alanine, but not by l-serine or glycine, resulted in a marked decrease in the activity. The β-methyl glycoside of MDP was found to be more active than the α-methyl derivative. 6-O-Stearoyl-N-acetylmuramyl-l-alanyl-d-isoglutamme showed activity. 相似文献
54.
Ryuhei Sasaki Michiko Mura Toshiyuki Takeuchi Chie Furihata Taijiro Matsushima Takashi Sugimura 《Biochimica et Biophysica Acta (BBA)/General Subjects》1976,428(3):619-626
Studies were made on changes in the contents of α-amylase (EC 3.2.1.1) in the pancreas and parotid gland of rats during postnatal devlopment, on the premature induction of this enzyme by hormones and on the existence of specific glucocorticoid receptors in these tissues.The amylase content in the pancreas increased from the 9th day after birth and reached the adult level on the 28th day, its content in the parotid gland increased rapidly from the 16th to 28th day after birth and then rose more gradually to the adult level.Injection of dexamethasone into rats 6–8 days after birth induced increase in the amylase of the pancreas but not the parotid gland. However, injection of dexamethasone into weanling rats 21–23 days after birth resulted in precocious induction of amylase in both tissues.Specific glucocorticoid receptors were detectable in the parotid gland of rats from 6 days after birth but were almost undetectable in the pancreas until adolescence. 相似文献
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Hideki Kajiura Ryo Kakutani Tsunehisa Akiyama Hiroki Takata Takashi Kuriki 《Biocatalysis and Biotransformation》2013,31(1-2):133-140
Two well-established methods to prepare glycogen are available: (1) extraction from natural resources such as shellfish and animal tissues; (2) synthesis from glucose-1-phosphate using two enzymes, α-glucan phosphorylase (EC 2.4.1.1) and branching enzyme (EC 2.4.1.18). We have developed a novel enzymatic process for glycogen production, in which short-chain amylose is first prepared from starch or dextrin by using isoamylase (EC 3.2.1.68), and then branching enzyme and amylomaltase (EC 2.4.1.25) are added to synthesize glycogen. Our enzymatic process, using isoamylase, branching enzyme and amylomaltase, is currently the most efficient for glycogen production. Furthermore, the molecular weight of glycogen is controllable in a range of 3.0×106 to 3.0×107 by adjusting some parameters of the reaction. 相似文献
60.
Anthi Katsiarimpa Kamila Kalinowska Franziska Anzenberger Corina Weis Maya Ostertag Chie Tsutsumi Claus Schwechheimer Frédéric Brunner Ralph Hückelhoven Erika Isono 《The Plant cell》2013,25(6):2236-2252
In eukaryotes, posttranslational modification by ubiquitin regulates the activity and stability of many proteins and thus influences a variety of developmental processes as well as environmental responses. Ubiquitination also plays a critical role in intracellular trafficking by serving as a signal for endocytosis. We have previously shown that the Arabidopsis thaliana ASSOCIATED MOLECULE WITH THE SH3 DOMAIN OF STAM3 (AMSH3) is a deubiquitinating enzyme (DUB) that interacts with ENDOSOMAL COMPLEX REQUIRED FOR TRANSPORT-III (ESCRT-III) and is essential for intracellular transport and vacuole biogenesis. However, physiological functions of AMSH3 in the context of its ESCRT-III interaction are not well understood due to the severe seedling lethal phenotype of its null mutant. In this article, we show that Arabidopsis AMSH1, an AMSH3-related DUB, interacts with the ESCRT-III subunit VACUOLAR PROTEIN SORTING2.1 (VPS2.1) and that impairment of both AMSH1 and VPS2.1 causes early senescence and hypersensitivity to artificial carbon starvation in the dark similar to previously reported autophagy mutants. Consistent with this, both mutants accumulate autophagosome markers and accumulate less autophagic bodies in the vacuole. Taken together, our results demonstrate that AMSH1 and the ESCRT-III-subunit VPS2.1 are important for autophagic degradation and autophagy-mediated physiological processes. 相似文献