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1.
J Mizuno N Takeda 《Comparative biochemistry and physiology. A, Comparative physiology》1988,91(4):733-738
1. A phylogenetic study of oxytocin (OXT)-like immunoreactive cells was performed by the PAP method in the central nervous system of invertebrates. 2. The immunoreactivity was detected in the nerve cells of Hydra magnipapillata of the Coelenterata; Neanthes japonica and Pheretima communissima of the Annelida; Oncidium verrucosum, Limax marginatus and Meretrix lamarckii of the Mollusca; and Baratha brassica of the Arthropoda. 3. No immunoreactive cells were found in Bipalium sp. of the Platyhelminthes; Pomacea canaliculata, Aplysia kurodai, Bradybaena similaris and Achatina fulica of the Mollusca; and Gnorimosphaeroma rayi, Procambarus clarkii, Hemigrapsus sanguineus, Helice tridens and Gryllus bimaculatus of the Arthropoda; Asterina pectinifera of the Echinodermata; and Halocynthia roretzi of the Protochordata. 4. These results demonstrate that an OXT-immunoreactive substance is widely present not only in vertebrates but also in invertebrates. 5. OXT seems to have been introduced into these invertebrates at an early stage of their phylogenetic history. 相似文献
2.
Yuji Inaba Yoshio Tanaka Sukemitsu Ishii Tomiaki Morimoto Kunihiko Sato Tuneyoshi Omori Minoru Matumoto 《Microbiology and immunology》1970,14(5):351-360
Replication of Ibaraki virus was not inhibited by 5-iodo-2′-deoxyuridine, indicating that the virus is an RNA virus. The virus was resistant to ether, chloroform and deoxycholate, sensitive to trypsin, very labile at acidic pH but stable at pH 6.4 or higher, and was resistant to repeated freezing and thawing. The virus was readily inactivated at 56 C or higher, was fairly stable at 37 C, and very stable at 4 C, while it rapidly lost infectivity when stored frozen at —20 C. The virus was readily sedimented by centrifugation at 40 000Xg for 60 min. It readily passed through membrane filters of 200 mμ pore size, passed through 100 μfilters but only with some titer loss and did not through 50 mμ filters. In these tests, the bluetongue virus used as a control behaved in the same manner as Ibaraki virus. These findings provide additional evidence for the similarity of Ibaraki virus to bluetongue virus which had been previously demonstrated on the basis of seasonal incidence, symptomatology and pathology of the diseases caused by these viruses and the behavior of the viruses in cell cultures, embryonated eggs and laboratory animals. The present study, however, provided no evidence for any serological relation between these two viruses. More Information is needed to reach a final decision on the classification of Ibaraki virus, particularly regarding the morphology of the virion, the doublestrandedness of the viral RNA and other basic features. 相似文献
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4.
Two species of fiddler crab, Uca tetragonon(Herbst, 1790) and Uca vocans(Linnaeus, 1758), which belong to the subgenus Gelasimus, dwell on rocky shores and muddy–sandy tidal flats, respectively, in Phuket Is., Thailand. We investigated their feeding ecology in relation to the morphology of their feeding organs: minor food-handling chelipeds and maxillipeds. U. tetragononfed chiefly on rocks covered by filamentous green algae. U. vocansfed on the emerged sand and in shallow water along the shoreline and in pools. While feeding, both crabs made sand pellets beneath their mouthparts and discarded them, indicating that they divided the matter scooped up with their minor chelipeds into edible and inedible fractions by using the maxillipeds in the water passing through their buccal cavity. The morphology of maxillipeds hardly differed between the two species, which means that both species are flotation-feeders. The morphology of their minor chelipeds, however, differed: the tips of the dactyl and pollex were flat in U. tetragononand pointed in U. vocans.When the minor cheliped was closed, U. tetragononhad a hemispherical space in the distal one-fourth of the gape, which was closed by the framing keratin layers and a few setae of the dactyl and pollex. On the other hand, U. vocanshad an ellipsoidal space in the distal half of the gape. We consider these morphological characters to be adaptations to the different feeding substrates for retaining more food-laden sediment. We discuss the role of the setae on the minor chelipeds on the basis of the morphological differences between populations of U. tetragononin Phuket Is. and East Africa where the crab inhabits muddy–sandy tidal flats. 相似文献
5.
Y. Saijo S. Takeda A. Scherer T. Kobayashi Y. Mada H. Taniguchi M. Yao S. Wakatsuki 《Protein science : a publication of the Protein Society》1997,6(4):916-918
Troponin is a ternary protein complex consisting of subunits TnC. TnI, and TnT, and plays a key role in calcium regulation of the skeletal and cardiac muscle contraction. In the present study, a partial complex (CI47) was prepared from Escherichia coli-expressed rabbit skeletal muscle TnC and fragment 1-47 of TnI, which is obtained by chemical cleavage of an E. coli-expressed mutant of rabbit skeletal muscle TnI. Within the ternary troponin complex, CI47 is thought to form a core that is resistant to proteolytic digestion, and the interaction within CI47 likely maintains the integrity of the troponin complex. Complex CI47 was crystallized in the presence of sodium citrate. The addition of trehalose improved the diffraction pattern of the crystals substantially. The crystal lattice belongs to the space group P3(1)(2)21, with unit cell dimensions a = b = 48.2 A, c = 162 A. The asymmetric unit presumably contains one CI47 complex. Soaking with p-chloromercuribenzenesulfonate (PCMBS) resulted in loss of isomorphism, but enhanced the quality of the crystals. The crystals diffracted up to 2.3 A resolution, with completeness of 91% and R(merge) = 6.4%. The crystals of PCMBS-derivative should be suitable for X-ray studies using the multiple-wavelength anomalous diffraction technique. This is the first step for elucidating the structure of the full troponin complex. 相似文献
6.
Kaeko Tozawa Eiji Arakawa Toshiyuki Chikuma Yoshihiro Oh-hashi Ryuichi Yajima Katsumichi Takeda Hiroshi Shinozaki† Takeshi Kato† 《Journal of neurochemistry》1990,55(3):745-749
Axonal transport of peptidylglycine alpha-amidating monooxygenase (PAM) activity was studied in rat sciatic nerves from 12 to 120 h after double ligations. The anterograde axonal transport increased and reached a plateau between 48 and 72 h and then decreased. The flow rate was 100 mm/day, and the molecular mass of the active entity was 70 kDa, which was determined by gel filtration. In contrast, there was no evidence for significant retrograde axonal transport. Anterograde axonal transport of immunoreactive cholecystokinin, a carboxy-terminal-amidated putative neuropeptide, was also found. These results suggest that PAM is transported by a rapid axonal flow and may play a role as a processing enzyme during transport or in the terminals of rat sciatic nerves. 相似文献
7.
Tuneyoshi Omori Yuji Inaba Tomiaki Morimoto Yoshio Tanaka Hiroshi Kurogi Minoru Matumoto 《Microbiology and immunology》1967,11(2):133-142
Five strains of bovine diarrhea virus were isolated from Japanese cattle using bovine tissue cultures. These are the first isolations of this virus from Japanese cattle to be reported. Of importance is the finding that the new isolates, which are non-cytopathogenic, induce an exaltation of Newcastle disease virus in bovine testicular cell culture. This finding has provided a laboratory tool whereby the assay of the virus and its neutralizing antibody can readily be performed. 相似文献
8.
9.
We separated two forms of arylalkylamine N-acetyltransferase (AANAT) from various organs of the American cockroach, Periplaneta americana. Both forms of the enzyme had an equivalent molecular mass of 28 kDa. One form isolated from the testicular accessory glands had high enzyme activity at acidic pHs. The isoelectric point was 5-6 and the substrate specificity was wider than the other type. The other isolated form from female midguts had a higher level of enzyme activity at basic pHs. These findings suggested that P. americana contains polymorphic AANAT, as is the case in Drosophila melanogaster. These forms differed not only in pH specificity, and substrate specificity but in chromatographic behavior and kinetic properties. Most of the organs we examined contained a mixture of the two forms since two types of AANAT activity were separated in different chromatographic fractions when two pH conditions were used for activity measurement. 相似文献
10.
Masuo Kondoh Emi Tasaki Saeko Araragi Masufumi Takiguchi Minoru Higashimoto Yoshiteru Watanabe Masao Sato 《European journal of biochemistry》2002,269(24):6204-6211
Zinc (Zn), an endogenous regulator of apoptosis, and has abilities both to induce apoptosis and inhibit the induction of apoptosis via the modulation of caspase activity. Due to the multifunctions of Zn, the intracellular Zn level is strictly regulated by a complex system in physiological and pathological conditions. The commitment of Zn to the regulation of apoptosis is not fully understood. In the present study, we investigated the role of intracellular Zn level in the induction of apoptosis in human leukemia cells (HL-60 cells) using a Zn ionophore [pyrithione (Py)]. Treatment of HL-60 cells with Zn for 6 h in the presence of Py (1 micro m) exhibited cytotoxicity in a Zn dose-dependent manner (25-200 micro m). Necrotic cells, assayed by trypan blue permeability, increased in number in a Zn dose-dependent fashion (50-100 micro m), but the appearance of apoptotic cells, assayed by formation of a DNA ladder and terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end-labeling method, peaked at 25 micro m, suggesting the dependence of intracellular Zn level on the execution of apoptosis. In fact, treatment with Py resulted in increases in intracellular Zn levels, and N,N,N',N'-tetrakis (2-pyridylmethyl)ethylenediamine, a cell-permeable Zn chelator, inhibited DNA ladder formation induced by Py/Zn treatment (1 micro m Py and 25 micro m Zn). Py/Zn treatment activated the caspases, as assessed by the proteolysis of poly(ADP-ribose) polymerase (PARP), which is a substrate of caspase, and activated p38 mitogen-activated protein kinase (p38MAPK), which is a transducer of apoptotic stimuli to the apparatus of the apoptosis execution. Z-Asp-CH2-DCB, a broad-spectrum inhibitor of caspase, attenuated proteolysis of PARP and DNA ladder formation by Py/Zn, indicating that apoptosis induced by Py/Zn is mediated by caspase activation. The p38MAPK-specific inhibitor SB203580 also inhibited induction of apoptosis by Py/Zn. Although SB203580 suppressed the proteolysis of PARP, Z-Asp-CH2-DCB did not inhibit the phosphorylation of p38MAPK, raising the possibility that apoptosis triggered by Py/Zn might be mediated by the p38MAPK/caspase pathway. 相似文献