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91.
Probable Contribution of Protein Phosphorylation by Protein Kinase C to Spicule Formation in Sea Urchin Embryos 总被引:3,自引:3,他引:0
Keiko Mitsunaga Shio Shinohara Ikuo Yasumasu 《Development, growth & differentiation》1990,32(3):335-342
The formation of spicules and development of pluteus arms in sea urchin embryos were strongly blocked by H-7 (1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride) but were not affected by HA1004 ( N -(2-guanidinoethyl)-5-isoquinolinesulfonamide hydrochloride). Archenteron formation occurred normally in the presence of these compounds. Late gastrulae (28 hr after fertilization) were exposed to 32 Pi for 30 min at 20°C, and then dissociated and their primary mesenchyme cells with spicules, embryo-wall cells and archenteron cells were separated. Then, the radioactivities in the protein fractions of these separated cells were measured. Results showed that culture of embryos with H-7 strongly inhibited 32 p incorporation into proteins in primary mesenchyme cells but caused little inhibition of its incorporations in embryo-wall cells and archenteron cells. The effective concentrations of H-7 for inhibition of 32 p incorporation were within the range that blocked spicule formation and growth of pluteus arms in embryos. HA1004 only slightly inhibited 32 p incorporation into protein in mesenchyme cells, embryo-wall cells and archenteron cells of embryos exposed to 32 Pi. Protein kinase C activity was detectable only in isolated primary mesenchyme cells associated with spicule structures. These suggest that phosphorylation of proteins by protein kinase C contributes to the formation of spicule structures. 相似文献
92.
In brain tissue a spectrin-like calmodulin-binding protein calspectin, or fodrin, is concentrated in a synaptosome fraction, where most of the calspectin is associated with the synaptic membranes. This endogenous calspectin was phosphorylated by protein kinase system(s) associated with the membranes. Here, we report the solubilization and partial purification of the membrane-associated calspectin kinase activity. The activity was resolved on a gel filtration column into two fractions, peaks I and II having estimated Mr of 800 000 and 88 000. The activity of peak I was dependent on the presence of both Ca2+ and calmodulin. Peak II revealed a basal activity in the absence of Ca2+ and calmodulin, which was stimulated 2-fold by addition of Ca2+. Calmodulin had no effect on the peak II activity. 相似文献
93.
Michio Ohba Keiko Ono Keio Aizawa Setsuo Iwanami 《Journal of invertebrate pathology》1981,38(2):184-190
Bacteriological and serological characteristics of three Bacillus thuringiensis isolates obtained in Japan were investigated. They formed typical rhomboidal parasporal inclusions but flagellar (H) antigens of these isolates were different from those of the known 17 H serotypes of B. thuringiensis. The three isolates were divided into two new serotypes (serotypes 18 and 19). The serotype 18 isolate (3–71) produced thermostable exotoxin and the inclusions of this isolate were toxic to larvae of the silkworm, Bombyx mori, but nontoxic to larvae of the mosquito, Aedes aegypti. The other isolate (119-72) belonging to serotype 18 produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. However, other bacteriological properties of the isolate 119-72 were similar to those of the isolate 3–71. The serotype 19 isolate (117-72) produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. Acid production from saccharose and the production of brownish purple pigment were observed in the two serotype 18 isolates, while neither of them was observed in the serotype 19 isolate. In other 29 biochemical properties tested, there was no difference among the three isolates. Based on these characteristics, the following two subspecies names are proposed: Bacillus thuringiensis subsp. kumamotoensis (serotype 18) for the type strain 3–71 and Bacillus thuringiensis subsp. tochigiensis (serotype 19) for the type strain 117-72. 相似文献
94.
95.
Complete nucleotide sequence of mouse immunoglobulin mu gene and comparison with other immunoglobulin heavy chain genes 总被引:34,自引:10,他引:24 下载免费PDF全文
We have determined the complete nucleotides sequence (2168 bases) of the immunoglobulin mu gene cloned from newborn mouse DNA. The cloned 13kb fragment contained the entire constant region gene sequence that is interrupted by three intervening sequences at the junction of domains as previously shown in the gamma 1, gamma 2 b and alpha genes. The amino acid sequence predicted by the nucleotide sequence agrees with that of the mu chain secreted by a myeloma MOPC104E except for 8 residues out of 448 residues. The homologous domains of the mu, gamma 1 and gamma 2b genes are more similar to each other than the different domains of the mu genes are. The result implicates that the class of the immunoglobulin heavy chain genes diverged after the heavy chain genes established the multi-domain structure. The short intervening sequences of the mu and gamma genes are more conserved than the coding sequences except for the COOH-terminal domains. The results implicate that the nucleotide sequence of the intervening sequence is under selective pressure, possibly to maintain a secondary structure of the nuclear RNA to be spliced. 相似文献
96.
97.
Hideaki Yamada Toru Nagasawa Haruyuki Ohkishi Bunsei Kawakami Yoshiki Tani 《Biochemical and biophysical research communications》1981,100(3):1104-1110
Synthesis of D-cysteine from 3-chloro-D-alanine and hydrogen sulfide is catalyzed by highly purified 3-chloro-D-alanine hydrogen chloride-lyase from . The synthetic reaction proceeds optimally at pH 8.5, as a function of enzyme concentration and incubation time. The enzymatically synthesized D-cysteine was isolated from the large scale reaction mixture and identified by physicochemical means. 相似文献
98.
The concentration of ACTH in extracts of rat anterior pituitary was measured by both radioimmunoassay and bioassay at different stages following adrenalectomy. Both types of ACTH activity decreased the day immediately following adrenalectomy but increased gradually afterwards. Immunological ACTH activity increased to 250% of the control value and biological ACTH activity increased to 490% of control value 3 weeks after adrenalectomy. The increase in biological ACTH activity occurred earlier, and the rate of increase was greater, than that of the immunological ACTH activity. The distributions of molecular weight forms of ACTH in extracts of anterior pituitary lobes was determined by gel filtration. Three molecular weight forms of immunoassayable ACTH were detected. Biological ACTH activity appeared in the 2nd and the 3rd peaks. A striking change was observed after adrenalectomy in the distribution of biologically active forms of ACTH. The ratio of biological ACTH activity to immunological ACTH activity in each peak changed at various stages after adrenalectomy. This indicated the heterogenous nature of the ACTH included in each peak. At 2 and again at 3 weeks, biological activity markedly increased until it exceeded the immunological ACTH activity in the 2nd peak. Dexamethasone had little influence on the elution profile of either immunoassayable and biologically active ACTH in gel filtration. Adrenalectomy may possibly have an effect on the intracellular posttranslational processing of ACTH precursors which leads to the development of biological ACTH activity. 相似文献
99.
Experimental transfer of the lung stage worms of Angiostrongylus cantonensis was performed between permissive hosts (rats) and between permissive (rat) and nonpermissive hosts (guinea pigs and rabbits). These worms from rats were rejected when implanted into nonpermissive hosts. Unexpectedly, similar worms did not survive well even in permissive hosts; the majority of recipient rats did not have first-stage larvae (L1) in their stools and, even when positive for L1, the number of the larvae shed was few. These findings contrast with the successful pulmonary arterial transfer of younger, intracranial-stage worms. It was shown that differences in rat strain between donor and recipient had no significant effect on the subsequent worm survival in recipient hosts. The alteration of maintaining conditions of the intrapulmonary worms, prior to transfer, in terms of temperature, media, and maintaining period, also showed no profound effect on the subsequent worm survival. The kinetics of precipitating and reaginic antibody levels in rats implanted with the intrapulmonary worms were analogous to those in rats with intracranial-stage worms. The findings indicate that some qualitative differences may exist between the worms obtained from two different sites. 相似文献
100.
Nucleotide sequence of 5S ribosomal RNA from Lingula anatina. A study on the molecular evolution of 5S ribosomal RNA from a living fossil 总被引:8,自引:0,他引:8
By chromatography on columns of DEAE-Sephadex A-50 and Sephadex G-100, and electrophoresis on polyacrylamide gel, 5S rRNA was purified from a low-molecular-weight RNA fraction extracted from the total tissues of Lingula anatina. Complete digests of the 5S rRNA with RNase T1 [EC 3.1.4.8] and pancreatic RNase [EC 3.1.4.22] were sequenced by conventional column chromatography procedures. The nucleotide sequence of this RNA was determined mainly by a chemical method for sequencing the RNA 3' end-labeled with 32P (1), with the complement of the oligonucleotide catalog obtained by the complete RNase digestions of the RNA. By comparing the sequences of several invertebrate, vertebrate, and Chlorella 5S rRNAs, a phylogenic tree of the rRNAs was constructed and the time of divergence of Lingula was estimated. 相似文献