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31.
S. Kawahara M. Yano H. Shimizu 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1994,174(1):111-120
A radular mechanosensory neuron, RM, was identified in the buccal ganglia of Incilaria fruhstorferi. Fine neurites ramified bilaterally in the buccal ganglia, and main neurites entered the subradular epithelium via buccal nerve 3 (n3). When the radula was distorted by bending, RM produced an afferent spike which was preceded by an axonic spike recorded at n3. The response of RM to radular distortion was observed even in the absence of Ca2+, which drastically suppressed chemical synaptic interactions. Therefore, RM was concluded to be a primary radular mechanoreceptor.During rhythmic buccal motor activity induced by food or electrical stimulation of the cerebrobuccal connective, RM received excitatory input during the radular retraction phase. In the isolated buccal ganglia connected to the radula via n3s, the afferent spike, which had been evoked by electrical stimulation of the subradular epithelium, was broadened with the phasic excitatory input. Since the afferent spike was also broadened by current injection into the soma, depolarization due to the phasic input may have produced the spike broadening.Spike broadening was also observed during repetitive firing evoked by current injection. The amplitude of the excitatory postsynaptic potential in a follower neuron increased depending on the spike broadening of RM.Abbreviations CBC
cerebrobuccal connective
- EPSP
excitatory postsynaptic potential
- n1,n3
buccal nerves 1 and 3
- RBMA
rhythmic buccal motor activity
- RM
radular mechanosensory neuron
- SMT
supramedian radular tensor neuron 相似文献
32.
Phylogenetic place of guinea pigs: no support of the rodent-polyphyly hypothesis from maximum-likelihood analyses of multiple protein sequences 总被引:3,自引:2,他引:1
Graur et al.'s (1991) hypothesis that the guinea pig-like rodents have an
evolutionary origin within mammals that is separate from that of other
rodents (the rodent-polyphyly hypothesis) was reexamined by the
maximum-likelihood method for protein phylogeny, as well as by the
maximum-parsimony and neighbor-joining methods. The overall evidence does
not support Graur et al.'s hypothesis, which radically contradicts the
traditional view of rodent monophyly. This work demonstrates that we must
be careful in choosing a proper method for phylogenetic inference and that
an argument based on a small data set (with respect to the length of the
sequence and especially the number of species) may be unstable.
相似文献
33.
34.
Yoshiharu Inoue Yoshitaka Iba Hiroshi Yano Kousaku Murata Akira Kimura 《Applied microbiology and biotechnology》1993,38(4):473-477
A high expression system of the -glutamylcysteine synthetase gene (gshl) of Escherichia coli B was constructed, and rapid purification of GSH-I was performed. The active site of GSH-I was analysed by chemical modification, and Lys, Arg and His residues seemed to be involved in the active site of the enzyme. Among them, His residues were substituted to Ala by site-directed mutagenesis, and His-150 was found to be essential for the activity of GSH-I.
Correspondence to: A. Kimura 相似文献
35.
Takao Yagi Takahiro Yano Akemi Matsuno-Yagi 《Journal of bioenergetics and biomembranes》1993,25(4):339-345
A comparison of the mitochondrial NADH-ubiquinone oxidoreductase and the energy-transducing NADH-quinone oxidoreductase (NDH-1) ofParacoccus denitrificans revealed that both systems have similar electron-transfer and energy-transduction pathways. In addition, both complexes are sensitive to the same inhibitors and contain similar electron carriers, suggesting that theParacoccus NDH-1 may serve as a useful model system for the study of the human enzyme complex. The gene cluster encoding theParacoccus NDH-1 has been cloned and sequenced. It is composed of 18,106 base pairs and contains 14 structural genes and six unidentified reading frames (URFs). The structural genes, URFs, and their polypeptides have been characterized. We also discuss nucleotide sequences which are believed to play a role in the regulation of the NDH-1 gene cluster andParacoccus NDH-1 subunits which may contain the binding sites of substrates and/or electron carriers. 相似文献
36.
Shuichi Yano 《Population Ecology》1994,36(1):63-71
This report shows that one of the most important roles of the flower nectar of an autogamous perennialRorippa indica (L.) Hieron is as an attractant for employing some ant species as a defense against herbivorous insects. The plant has flowers from spring to early winter. Its flower nectar is frequently stolen by some ant species (hereafter cited as ants) which also feed on small herbivorous insects on the plant. Internations among the tritrophic levels (R. indica, herbivores, ants) were experimentally examined and the followings became clear. (1) Ants were attracted toR. indica in search of its flower nectar. (2) The gradual secretion of flower nectar seemed to detain ants on the plant. (3)Pieris butterfly lavae were the major herbivores onR. indica and were potentially harmful to the plant. (4) The presence of ants reduced the survival rate ofP. rapae larvae onR. indica. (5) The presence of ants reduced the feeding damage toR. indica. (6) The disadvantage of nectar use by ants seemed to be minimal for the plant since the ants did not disturb the other flower visitors. These facts suggest a mutualistic relationship betweenR. indica and ants. That is, the flower nectar serves as an indirect defense against herbivorous insects. 相似文献
37.
Kazunari Yano 《Environmental Biology of Fishes》1993,38(1-3):59-71
Synopsis The reproductive biology of 385 male and 373 female slender smoothhounds,Gollum attenuatus, collected from New Zealand waters was examined. Size at maturity for both sexes was about 700 mm TL. Litter size was usually two. The sex ratio of embryos was 1:1. The right ovary ovulated 50–100 ova, 4–8 mm in diameter, and 30–80 ova were enclosed in each egg capsule. Only one embryo developed from the many ova in each egg capsule, the other undeveloped ova were ingested and passed to an external yolk sac which formed the yolk supply for the developing embryo. 相似文献
38.
Masamichi Yamashita 《Biological Sciences in Space》2003,17(1):51-53
Space agriculture is a concept of synthesis and operation of closed ecological system for controlling living environment and supplying materials in order to sustain life and to meet metabolic needs of space crew. It revitalizes metabolites and other excretion of crew for their recycled usage. It is an advanced concept for life support for long and large scaled manned space missions, where open loop system for materials cycle is not feasible to apply. Several issues, such as cost-benefit analysis with considering benefits of amenity and psychological factors of crew, are discussed in this essay, together with reliability and productivity of biological systems. Studies on plant physiology for inter-organismal interaction contribute to design work for space agriculture, and associate with our engagements to our future, sustainable development of our civilization both on the earth and extending to outer space. 相似文献
39.
40.
A link between increased transforming activity of lymphoma-derived MYC mutant alleles, their defective regulation by p107, and altered phosphorylation of the c-Myc transactivation domain. 总被引:5,自引:4,他引:1
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A T Hoang B Lutterbach B C Lewis T Yano T Y Chou J F Barrett M Raffeld S R Hann C V Dang 《Molecular and cellular biology》1995,15(8):4031-4042