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Volume 13 (1988)
- Issue 6 Pages 459-
- Issue 5 Pages 359-
- Issue 4 Pages 271-
- Issue 3 Pages 193-
- Issue 2 Pages 105-
- Issue 1 Pages 1-
Volume 13, Issue 5
Displaying 1-9 of 9 articles from this issue
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Shigeo Terada, Koichi Nobori, Toshihiko Utsumi, Kozo Utsumi1988 Volume 13 Issue 5 Pages 359-371
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSWe have studied protein acylation in neutrophils of guinea pigs using [3H]myristate. A large number of neutrophil proteins were acylated with exogenously added myristic acid. The myristoylation was detected on 110, 77, 56, 54, 52, 42, and 37 kDa proteins. These myristoylations were stronger in peripheral blood than in peritoneal cells. Myristic acid was found to be covalently linked by an amid bond to these proteins since the proteins were resistant to boiling, chloroform/methanol and hydroxylamine treatment. Most myristoylated proteins appeared to be associated with the membrane fraction, while some of the proteins such as 77 kDa one was distributed also in the cytoplasm and translocated from the cytoplasm to the plasma membtrane by stimulation. Lysozyme was myristoylated in vitro by the N-hydroxysuccinimide ester of myristic acid. The myristoylated lysozyme had an ability to be associated with phospholipid liposomes, and the membrane-associated lysozyme became a substrate of the rat brain Ca2+- and phospholipid dependent protein kinase (protein kinase C). These results indicate that myristoylation in neutrophil proteins may have an important role in metabolic regulation through their membrane association.View full abstractDownload PDF (9122K) -
Shohei Maekawa, Kunihiro Ohta, Hikoichi Sakai1988 Volume 13 Issue 5 Pages 373-385
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSWe have previously described some of the characteristics of an actin binding protein, 53 K protein, purified from porcine brains. The purifica-tion procedure was revised in order to investigate of this actin binding protein further. A Scatchard plot analysis showed that the association constant bet-ween actin and the 53 K protein has around the same value as those reported for the fascin-actin and for the filamin-actin interactions. The binding experiments also demonstrated the occurance of competitive binding with other actin binding proteins such as filamin, a-actinin, caldesmon and tropomyosin for the actin filament. Antibody was produced against brain 53 K protein and further purified on an affinity column. Immunoblot analysis using the antibody showed that this pro-tein is localized in both the soluble and membraneous fraction of the brain. Other tissues such as liver and lung also contain 53 K protein. The immunoblot analysis also revealed that the gelation product of rat brain extract described by Palmer et al. contains immunoreactive polypeptides having slightly lower molecular weights and more basic isoelectric points than porcine brain 53 K pro-tein. Immunological localization of the 53 K protein within HeLa and BS-C-1 cells showed that this protein is distributed throughout the cell in small granules, and in some regions of the cell, these granules were aggregated into much larger granules.View full abstractDownload PDF (10457K) -
Yukio Kiho1988 Volume 13 Issue 5 Pages 387-405
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSTwo methods of qualitative analysis of sequence distribution in DNA and protein are presented. The first method is based on the finding that the freguency of occurrence of each nucleotide in a defined sequence with func-tional significance more or less deviates from uniform distribution. The devia-tion found in this defined sequence seems to parallel the function of this se-quence. In the second method, two model compounds (trypsin and its inhibitor) have been used to see the topological fit between their local structures. Acrophilicity parameter for amino acid was used to construct the topological structure. Both methods may find practical application in algorithms to design functional DNA and protein molecules.View full abstractDownload PDF (1190K) -
Yasuhiro Tsunoda, Susumu Yodozawa, Yutaka Tashiro1988 Volume 13 Issue 5 Pages 407-415
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSDistribution and temporal change of free calcium concentration ([Ca2+]i) in single guinea pig gastric chief cells were visualized by a digital imaging microscope equipped with a microspectrofluorometer. The distribution was not homogeneous; a higher [Ca2+]i area was often localized in some restricted regions of the endoplasm and also at the peripheral cytoplasm just beneath the plasma membrane. When stimulated with cholecystokinin, [Ca2+1]i increased transiently in the apical peripheral cytoplasm and in the endoplasmic regions. This Ca2+ mobilization which precedes the biphasic pepsinogen secretion was composed of a rapid Ca2+ release from the intracellular store(s) as well as a rapid and a more sustained Ca2+ entry from the extracellular space.View full abstractDownload PDF (3052K) -
Eisuke Nishida, Kazuyuki Tobe, Takashi Kadowaki, Masato Kasuga, Chikak ...1988 Volume 13 Issue 5 Pages 417-423
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSInsulin-like growth factor-I (IGF-I) stimulated the phosphorylation of cytoskeletal 350-kDa and 300-kDa proteins which were immunoprecipitated with antibodies against brain high molecular weight microtubule-associated proteins in quiescent rat 3Y1 cells. The data on the effec-tive concentrations of IGF-I and 125I-labeled IGF-I binding indicated that type I IGF receptors mediate this IGF-I effect. Platelet-derived growth factor (PDGF) as well as phorbol ester (TPA) also stimulated the phosphorylation of these proteins. These proteins, whether immunoprecipitated from cells stimulated by insulin, IGF-I, TPA, PDGF, or epidermal growth factor, produced very similar phosphopeptide mapping patterns irrespective of the stimulant. The results suggest the possibility that these growth factors and phorbol esters may activate a common protein kinase which is responsible for the phosphorylation of the 350-kDa and 300-kDa proteins in cells.View full abstractDownload PDF (3955K) -
Takamitsu Hori, Satoshi Kashiyama, Naoto Oku, Makio Hayakawa, Sayumi S ...1988 Volume 13 Issue 5 Pages 425-433
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSHuman recombinant tumor necrosis factor (TNF) stimulated the growth of confluent human fibroblasts (FS-4) in the presence of fetal calf serum. Epidermal growth factor (EGF) similarly stimulated cellular growth; however other mitogenic factors such as insulin, fibroblast growth factor, 12-0-tetradecanoyl-phorbol-12-acetate and Ca2+ ionophore A23187 did not. The growth-stimulating action of TNF was not synergistic with the activity of EGF in the presence of serum. TNF induced a rapid increase in the binding of transferrin to the cell surface, followed by a return to the basal level within 5 min. A similar increase in transferrin binding was observed in FS-4 cells ex-posed to EGF. In contrast, insulin caused a prolonged stimulation of transferrin binding. These results suggest that TNF and EGF generate similar or identical intracellular signals for cellular growth and the regulation of transferrin receptor expression.View full abstractDownload PDF (983K) -
Chieko Mineo, Toku Kanaseki, Masayasu Enomoto, Shoji Ohkuma, Tatsuya T ...1988 Volume 13 Issue 5 Pages 435-443
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSThe mechanism through which nonmembranous lipid inclu-sion bodies consisting of cholesteryl esters accumulate in the cytoplasm was studied. Most lipid inclusion bodies in macrophages after 24 h incubation with anisotropic cholesteryl oleate liquid crystals were surrounded by a limiting mem-brane. The limiting membrane, however, could not be observed after further incubation for 48 h in the presence of esterastin, which is known to be an inhibitor of lipase and esterase. Under these conditions, the levels of hydrolysis and re-esterification of cholesteryl esters were less than 15% and 5% of the control ones, respectively.
These results suggest that the inclusion bodies were transferred from lysosomes to the cytoplasm, with partial hydrolysis of cholesteryl esters, in addition to through the pathway via microsomes.View full abstractDownload PDF (1056K) -
Claudia M.C. Batista, Marlene Benchimol, Narcisa L. Cunha e Silva, Wan ...1988 Volume 13 Issue 5 Pages 445-453
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSWe used monoclonal antibodies specific for acetylated and nonacetylated a-tubulin to detect and to localize microtubules containing acetylated a-tubulin (stable microtubules) in the pathogenic protozoa Tritrichomonas foetus and Trichomonas vaginalis. SDS-PAGE analysis showed that tubulin is amajor proteinof both parasites, being enriched in cytoskeletal preparations of whole cells extracted with Triton X-100. The monoclonal antibodies, which recognize all isoforms of a-tubulin (B-5-1-2) and only acetylated a-tubulin (6-11B-1), bind to the tubulin of T. foetus and T.vaginalis as seen by immunoblotting. Tubulin-containing structures were localized using immunofluorescence microscopy and transmission electron microscopy of the whole cytoskeleton previously incubated in the presence of the anti-tubulin antibodies and a second antibody-gold complex, and then processed using the negative staining or replica techniques. The results obtained indicate that, in addition to the flagellar microtubules, those which form the peltar-axostyle system represent stable microtubules containing acetylated alpha-tubulin.View full abstractDownload PDF (1067K) -
Tatyana Tenkova, George N. Chaldakov1988 Volume 13 Issue 5 Pages 455-458
Published: 1988
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSWe report here on a structural association of single cilia, via their striated rootlets, with the Golgi complex in epithelial cells and stromal fibroblasts of rabbit ciliary processes of the eye. The structure is designated a Golgi-cilium complex and its likely role in aqueous humor production is discussed.View full abstractDownload PDF (555K)
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