To evaluate the thermal insulation performance of interior fabrics of curtains and carpet, a chamber with a house skin was used. Chambers of four types with a house skin were prepared as a thermally insulated form or a non thermally insulated form, with single glazed window glass or double glazed window glass. The electrical consumption of a heater in the chamber with the house skin was measured using a digital power meter. The electrical consumption of the heater was lower in each structure when using curtains and carpet. Results confirmed that the curtains and carpet were effective to control the heat loss from floors and the windows. Moreover, the heater electrical consumption increased linearly with the increased average heat transmission coefficient of the house skin of each chamber with a house skin. Electrical consumption showed good correlation with the average heat transmission rate of the chamber with a house skin.

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環境保全機能を備えた持続的養魚システムの開発を目的として, 同一生簀内でマダイと不稔性アナアオサ変異種 (以下, アオサと略) の複合養殖を行い, その生簀の酸素と炭酸ガスの相対収支の面から本養魚システムの効果を検討した。供試マダイは当センターで種苗生産した3年魚であり, 実験開始時の平均魚体重は654gであった。アオサは実験区生簀の全表面に「浮き流し網」で栽培し, 遮光用寒冷紗は施さなかった。対照区は, 在来法に準じ, 生簀上部を寒冷紗で覆いを施し, アオサの栽培は行わなかった。実験区のマダイにはその生簀もしくは同海域に自生するアオサを2% (乾燥) の割合でペレットに添加給餌した。また, いずれの区も投薬は行わなかった。飼育実験は1993年8月1日から開始した。ここでは, 同年9, 月27～30日にラジオメータ社ABL330で観測したpO₂とpCO₂の相対収支について検討した。その結果, 対照区の酸素および炭酸ガスをそれぞれ100%として換算すると, 実験区の酸素は109%に増加し, 炭酸ガスは96%に減少していることがわかった。つまり, 実験区は対照区に比べ, 酸素で9%増加, 炭酸ガスで4%減少, という結果が得られた。なお, その時期における2週間ごとのアオサの成長倍率は20～23倍であった。

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ATP (GTP) hydrolysis was clearly demonstrated by using at most 16 pmol of yeast peptide elongation factor 3 (EF-3) in the absence of ribosomes. However, the highly active yeast ribosomes (up to 48 pmol) displayed virtually no ATPase (or GTPase) activity in the absence of EF-3. Several lines of evidence indicated that both the catalytic and binding sites of the ATPase reside in the elongation factor itself, not on the ribosomes. The patterns of protection by various nucleoside triphosphates against tryptic digestion of EF-3, reflecting the wide substrate specificity of the ATPase, confirmed that the active center of the endogenous ATPase is located on the factor itself and not on contaminants. The intrinsic activity was stimulated up to two orders of magnitude by the presence of the yeast ribosomes fully active in polyphenylalanine synthesis. The activation was achieved by enhancing the catalytic activity (k_cat) to a much greater extent than the binding affinity (K_m). On the other hand, the ribosome-activated ATPase activity was revealed to inherit its wide substrate specificity from the intrinsic property of EF -3, which shows an affinity to various XTPs, including pyrimidine- and purine-nucleoside triphosphates, irrespective of 2' - hydroxylation of the sugar moiety. From experiments on protection against tryptic digestion, we determined that intricate conformational changes of the factor molecule occur upon interaction with the substrate XTP and ribosomes.

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EF-3 is a translational elongation factor specific to yeasts and fungi. Its carboxy-terminal region contains three lysine-clusters and is very basic. The region has been reported to be responsible for the interaction with ribosomes [Ishiyama, A., Ogawa, K., & Miyazaki, M. (1992) in Abstracts of the 15 th Annual Meeting of the Molecular Biology Society of Japan, p.190]. To find specific inhibitors for the interaction of EF-3 with ribosomes, the effects of two basic polyamino acids, poly-L-(Lys) and poly-L-(Arg), and two acidic polyamino acids, poly-L-(Asp) and poly-L-(Glu), were examined using two assay systems for ATPase of EF-3. One was for the ribosome-activated ATPase and the other for the intrinsic (ribosome-independent) ATPase of EF-3. Basic polyamino acids were expected to act as analogues of the carboxy-terminal region of EF-3, and acidic ones to interact with EF-3. The basic polyamino acids inhibited the ribosome-activated ATPase, but they also inhibited the intrinsic one more effectively. Acidic polyamino acids, poly-L-(Asp) and poly-L-(Glu), inhibited the ribosome-activated ATPase but not the intrinsic one. Thus, acidic polyamino acids could be specific inhibitors of the interaction between EF-3 and ribosomes. Furthermore, a system for detecting the binding of EF-3 to ribosomes was constructed. That is, ribosome-bound EF-3 was detected by measuring the ATPase on precipitated ribosomes after a mixture of EF-3 and ribosomes had been ultracentrifuged. Using this system, poly-L-(Asp) was shown to inhibit the binding of EF-3 to ribosomes directly.

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Electron microscopic observation was carried out on digestive system of immature D-stage larvae, early D-stage larvae, early umbonal larvae, early pediveliger, early spat and seed in Pinctada fucata. On and after early D-stage, alimentary canal consisted of esophagus, anterior stomach, posterior stomach, style sac, intestine, and digestive gland. The length and diameter of esophagus grew with increase of shell length. At the early D-stage, microvilli of anterior stomach were as long as those of posterior stomach. On and after early umbonal stage, microvilli of anterior stomach did not exist, while those of posterior stomach were extending. Style sac bore dense cilia of uniform length on and after early umbonal stage. Crystalline style in style sac and stomach were formed in early pediveliger. Intestine came to curve at early umbonal stage, and then the curvature became complicated according to growth. Digestive gland at early D-stage consisted of the cells with a large amount of rough-surfaced endoplasmic reticula. The gland grew digestive diverticula which consisted of two kinds of cells until umbonal stage. Mid gut appeared at early pediveliger. Wandering cells adjacent to digestive system of planktonic larva extended considerably long psedopodia which are likely to be basal lamina. The metamorphosis results in that growing direction of the posterior body wall and digestive diverticula changes from dorsoventral axis to antero-posterior axis. The wrenchs of viscus took place in early umbonal stage and metamorphic period. These periods correspond with the critical periods when many larvae often die. The growth rate of shell length corresponded with an increase of feeding which is related closely with a development of digestive system.

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Growth of shell length and development of soft tissues of Pinctada fucata larvae were observed mainly using an electron microscope. The veliger growth was divided into three stages ; i.e. slow growth during D-stage, rapid growth during umbonal stage and little growth during a few day before attachment. Alimentary canal became continue through the body, and differentiated esophagus, anterior stomach, posterior stomach, rudiment of digestive gland, rudiment of style sac and intestine in early D-stage. Digestive diverticula have developed from rudiment of digestive gland until early umbonal stage. Crystalline style appeared in the style sac of early pediveliger. The oil droplet-like granules in D-stage originated from egg and became scare until umbonal stage. Another granules which may be formed by feeding instead of glanules in D-stage larvae emerged in alimentary canal at the stages of early umbonal larvae to early pediveliger. Rudiment of byssal gland appeared between posterior body wall and digestive diverticula, and the foot emerged as an apophysis of posterior body wall at dorsal part of byssal gland in early umbonal stage. Eye spot, pedal ganglia, statocysts, visceral ganglia and rudimental heart differentiated from the posterior body wall of early pediveliger. Anterior adductor muscle and retractor muscles of velum in early D-stage were not striated, but both the muscles appear to be striated in early umbonal stage. Posterior adductor muscle appeared prior to attachment, which was not striated. Cerebral ganglia connection with apical organ protruded pleural ganglia toward posterior body wall. A pair of eye spots situated on either side of pedal ganglia, which connected pleural ganglia with a lot of granules. Mantle edge of early pediveliger divided into two foldst.

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For cultured pearl production, a mantle allograft from a donor is implanted intoa recipient gonad together with a small inorganic bead. Encapsulation of the grafts by hemocytes follows. The mantle allograft's outer epithelial cells subsequently emigrate along the inside of the hemocyte capsule, and eventually form a follicle, called a pearl sac, surrounding the bead. To clarify thecell types involved and timing of mitotic activity in the process of pearl sac formation, pearl oysters at various phases of pearl sac formation were injected with a thymidine analog, 5-bromo-2'-deoxyuridine (BrdU), and dividing cells labeled with BrdU were visualized with anti-BrdU antibody. At 4 days after implantation, the epidermal cells (dominant cells in the outer epithelium) of the allograft initiated active proliferation and emigration. Their mitoses continued during emigration and after establishment of the pearl sac. No incorporation of BrdU into the other two types of mantle epithelial cells (mature mucous cells and cells with large granules) was observed. In the gonad surrounding the pearl sac, a large number of connective tissue cells among gonadal follicles and around the intestine showed peak mitotic activity around one week after the operation, which implied activation of hemocyte production.

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Peptide elongation factor 3 (EF-3), which is widely present in yeasts and fungi (Eumycota), does not occur in another lower eukaryote, the unicellular protozoan Tetrahymena pyriformis, as was shown by the following findings: (a) there is no activity to satisfy the EF-3 requirement of yeast ribosomes in the post-ribosomal supernatant fraction from Tetrahymena, and (b) the Tetrahymena ribosomes displayed their full capacity for polyphenylalanine synthesis with purified EF-1α and EF-2 alone from either Tetrahymena or yeast, and their activity on the Tetrahymena ribosomes was not further enhanced by the addition of yeast EF-3, in contrast to the case of the yeast ribosomes. However, as a substitute for the ribosome-activated nucleotidase activity of EF-3, Tetrahymena ribosomes were shown to harbor strong, firmly bound ATPase and GTPase activities, which probably involve the same active site. The ribosome-bound ATPase activity was inhibited by a polyclonal antibody raised against yeast EF-3 with the same inactivation profile as that of polyphenylalanine synthesis on Tetrahymena ribosomes, indicating that the ribosomal ATPase plays an essential role in the elongation process on Tetrahymena ribosomes as previously revealed in the yeast system. It was also shown that the ribosomal nucleotidase plays a pivotal role in the elongation cycle in other eukaryotes.

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Cytoplasmic elongation factor 1α (EF-aα) was purified to homogeneity in high yield from the two different yeasts Saccharomyces carlsbergensis (S. earls.) and Schizosaccharomyces pombe (S. pombe). The purification was easily achieved by CM-Sephadex column chromatography of the breakthrough fractions from DEAE-Sephadex chromatography of cell-free extracts. The basic proteins have a molecular weight of 47, 000 for the S. carts. factor and of 49, 000 for the S. pombe factor. While the purified yeast EF-1αs function analogously to other eukaryotic factors and the E. coli EF-Tu in Phe-tRNA binding and polyphenylalanine synthesis, the yeast factor unusually hydrolyzed GTP on yeast ribosomes upon addition of Phe-tRNA in the absence of poly (U) as mRNA. This novelty is probably owing to the yeast ribosomes, which are assumed to lack elongation factor 3-equivalent component (s). Trypsin and chymotrypsin selectively cleaved the two yeast factors to generate resistant fragments with the same molecular weight of 43, 000 (by trypsin) and of 44, 000 (by chymotrypsin), respectively. Those cleavage sites were characteristically protected by the presence of several ligands bound to EF-1α such as GDP, GTP, and aminoacyl-tRNA. Based on the sequence analysis of the fragments generated by the two proteases, the partial amino acid sequence of the S. earls. EF-1α was deduced to be in accordance with the N-terminal region covering positions (1) to 94 and two Lys residues at the C-terminal end of the predicted total sequence of the Saccharomyces cerevisiae (S. cerev.) factor derived from DNA analysis, except for a few N-terminal residues, confirming the predicted S. cerev. sequence at the protein level. EF-1β and EF-1βγ were isolated and highly purified as biologically active entities from the two yeasts. EF-1βγs from the two yeasts have the same molecular weight of 27, 000, whereas component γ of the S. earls. EF-1βγ showed a higher molecular weight (47, 000) than that of the S. pombe factor (40, 000). It was also shown that a stoichiometric complex was formed between EF-1α and EF-1βγ from S. pombe. Furthermore, a considerable amount of Phe-tRNA binding activity was distributed in the EF-1H (probably EF-1αβγ) fraction from freshly prepared cell-free extracts of yeast.

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The stimulatory effect of peptide elongation factor 3 (EF-3), which is uniquely required for the yeast elongation cycle, on the step of binding of aminoacyl-tRNA (AA-tRNA) to ribosomes has been investigated in detail. Yeast EF-lα apparently functions in a stoichiometric manner in the binding reaction of AA-tRNA to the ribosomes. The addition of EF-3 and ATP to this binding system strikingly stimulated the binding reaction, and the stimulated reaction proceeded catalytically with respect to both EF-1α and EF-3, accompanied by ATP hydrolysis, indicating that EF-3 stimulated the AA-tRNA binding reaction by releasing EF-lα from the ribosomal complex, thus recycling it. This binding stimulation by EF-3 was in many respects distinct from that by EF-1βγ. The idea that EF-3 may participate in the regeneration of GTP from ATP and the formed GDP, as indicated by the findings that the addition of EF-3 along with ATP allowed the AA-tRNA binding and Phe polymerization reactions to proceed even in the presence of GDP in place of GTP, was not verified by the results of direct measurement of [³²P]GTP formation from [γ-³²P] ATP and GDP under various conditions. Examination of the stability of the bound AA-tRNA disclosed the different binding states of AA-tRNA on ribosomes between in the cases of the complexes formed with EF-1α alone, or factor-independently, and with EF-1α and EF-3. Furthermore, we found that whereas the EF-1α-promoted reaction allowed the binding of noncognate AA-tRNA to a certain extent, the EF-3-stimulated reaction strictly selected to bind only cognate AA-tRNA correctly pairing between codon and anticodon. Thus, we concluded that, for AA-tRNA binding to ribosomes, at first EF-1α carries AA-tRNA in the ternary complex with GTP to the ribosomal introducing site (I-site) with a little binding of noncognate AA-tRNA, and then EF-3 plays a key role in the strict selection of cognate AA-tRNA and in its transfer from the I- to the A-site, by changing its binding state, accompanied by ATP hydrolysis.

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現在日本では異なる抗原由来の2種類のB型肝炎ワクチンが市販されている．通常1回のシリーズ（6か月間に3回接種）では同じ製品が使用されるが，1シリーズ中に異なる抗原由来のB型肝炎ワクチンを接種した場合の抗体獲得について検討された報告は少ない．今回，1シリーズ中に異なる抗原由来のB型肝炎ワクチンを接種した場合の抗体獲得について検討した．

過去にB型肝炎ワクチン未接種であり，HBs抗体陰性が確認された被験者で，3回目を異なる抗原由来のB型肝炎ワクチンを接種した群を対象群（A群），3回全て同じB型肝炎ワクチンを接種した群をコントロール群（B群）とした．ワクチンの投与は皮下注で行い，HBsAb定量およびHBsAb定性は採血で測定し，10.00 COI以上をHBsAb陽性と判定した．有害事象は3回接種後の副反応を調査票で収集し，CTCAE Ver.4.0にて評価した．

A群は9名，B群は7名であり，両群ともに全例で抗体獲得が確認された．有害事象はA群で3件，B群で1件認められたが，いずれもGrade 1であった．A，B群合わせた副反応の内訳は注射部位の疼痛3件，皮膚硬結1件であり，重篤な副反応を呈した症例はなかった．

今回認められた有害事象はいずれもワクチンに共通した副反応であると考えられ，1シリーズ中に異なる抗原由来のB型肝炎ワクチンを接種しても良好な抗体獲得が得られる可能性が示唆された．

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Drosophila calpain (Dm-calpain) produced in Escherichia coli has a distinct Ca²⁺-dependent activity. By using a recombinant Dm-calpain, we searched for its substrates occurring in Drosophila ovaries, where Dm-calpain is expressed. Among a number of major proteins, several proteins in a salt-extracted fraction were selectively degraded by Dm-calpain in a Ca²⁺-dependent manner. The major substrates were identified by microsequencing the lysylendopeptidase-digested proteins. Three ribosomal proteins, the L5, L7, and L8 subunits of the 60S ribosome, were found to be potential Dm-calpain substrates. In addition, the α subunit of elongation factor-1 (EF-1α), a multi-functional protein involved in both protein synthesis and cytoskeletal regulation, was shown to be cleaved by Dmcalpain into several distinct fragments when expressed as a GST-fusion protein. Endogenous EF-1α in ovary extracts was also shown by western blot analysis to be similarly degraded. These observations suggest that Dm-calpain may regulate protein synthesis and cytoskeletal structure through its degradative or processing activity.

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  Eukaryotic polypeptide elongation factor EF-1 is not only a major translational factor, but also one of the most important multifunctional (moonlighting) proteins.

  EF-1 consists of four different subunits collectively termed EF-1αββ′γ and EF-1αβγδ in plants and animals, respectively. EF-1α•GTP catalyzes the binding of aminoacyl-tRNA to the A-site of the ribosome. EF-1ββ′γ (EF-1β and EF-1β′), catalyzes GDP/GTP exchange on EF-1α•GDP to regenerate EF-1α•GTP. EF-1γ has recently been shown to have glutathione S-transferase activity.

  EF-2 catalyzes the translocation of peptidyl-tRNA from the A-site to the P-site on the ribosome. Recently, molecular mimicry among tRNA, elongation factors, releasing factor (RF), and ribosome recycling factor (RRF) has been demonstrated and greatly improved our understanding of the mechanism of translation.

  Moreover, eukaryotic elongation factors have been shown to be concerned or likely to be concerned in various important cellular processes or serious diseases, including translational control, signal transduction, cytoskeletal organization, apoptosis, adult atopic dermatitis, oncogenic transformation, nutrition, and nuclear processes such as RNA synthesis and mitosis.

  This article aims to overview the recent advances in protein biosynthesis, concentrating on the moonlighting functions of EF-1.

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