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971.
Larvae of pit-building antlions are expected to be more efficient at capturing prey than those of non-pit-builders. To test this prediction, feeding behaviors were compared in the same experimental conditions among pit-building Baliga micans and Myrmeleon bore, and non-pit-building Distoleon contubernalis. The number of prey eaten did not differ between species. D. contubernalis larvae used the walls of the experimental chamber as fence traps to capture prey. In the field, they were also found near edges of natural barriers, such as rocks, stones, tree roots, and plant stems. Artificial pitfall traps captured more arthropods near the edges of fences than farther from them. Larvae of the two pit-building species were located in the central part of the experimental chamber. In their natural habitats, the number of arthropods captured by artificial pitfall traps increased with pit size; thus, larger pits may be more efficient for capturing prey. In conclusion, pit-building and non-pit-building antlion larvae are both efficient hunters; the former hunt efficiently by making larger pitfall traps, and the latter do so by waiting for prey at the edge of the natural fences along which arthropods walk. 相似文献
972.
Satomura Takenori Hayashi Junji Ohshida Tatsuya Sakuraba Haruhiko Ohshima Toshihisa Suye Shin-ichiro 《Extremophiles : life under extreme conditions》2018,22(6):975-981
Extremophiles - A gene-encoding a dye-linked d-lactate dehydrogenase (Dye-DLDH) homolog was identified in the genome of the hyperthermophilic archaeon Thermoproteus tenax. The gene was expressed in... 相似文献
973.
Nakamura Shizuka Fukuma Koichi Wada Kazushige Ueda Mayuko Hayashi Mitsuo 《Sleep and biological rhythms》2018,16(3):351-356
Sleep and Biological Rhythms - The nocturnal sleep of train drivers is apt to be short and their lifestyle become irregular because they drive at midnight and early in the morning. As a result,... 相似文献
974.
Sayo Tomatsu Keita Ogiso Kazuya Fukuda Mayumi Deki Shin-Ichi Dewa Hisaya Manabe Makoto Sakurai Akihiko Shinomiya Tomoki Sunobe 《Ichthyological Research》2018,65(4):502-506
The gobiid fish, Trimma caudomaculatum, lives in groups. We investigated group structure, mating system and bidirectional sex change of this species. Four groups examined contained more than two males. The males were significantly larger than the females. By the observations in aquarium, the males occupied a nest and the females visited the nest for spawning. While there was no specific pair bond, the males mated with multiple females. Hence, this species establishes multi-male groups. In the experiments, four larger females had changed sex to male among 25 females. The smallest male changed to female in the group of four males. 相似文献
975.
Cantharidin world in air: Spatiotemporal distributions of flying canthariphilous insects in the forest interior 下载免费PDF全文
The natural community in which the members interact using a toxic terpenoid cantharidin is named the “cantharidin world.” In previous studies, however, the members of this world have been surveyed only on the forest floor by setting pitfall traps with cantharidin as an attractant. In this study, we set cantharidin traps at various heights above the forest floor to investigate the structure and functional diversity of the canthariphilous flying insect community in the forest above‐ground space. A total of 3,168 arthropods were collected by the traps; among them, six species were more attracted to cantharidin than to control traps. Pseudopyrochroa brevitarsis and P. laticollis (Colecoptera: Pyrochroidae) both appeared for a short time during spring, but the latter species tended to use a lower layer of the forest. Clavicollis fugiens (Coleoptera: Anthicidae) also appeared in spring and flew near the ground. In these beetles, the attracted individuals were mostly males; they may use the obtained cantharidin for nuptial gifts to the female. Atrichopogon femoralis, A. insularis and Atrichopogon sp. (Diptera: Ceratopogonidae) were collected widely in the forest above‐ground space. These midges were almost females, probably because only females of these insects use chemical cues, including cantharidin, for searching for arthropods from which to suck hemolymph. 相似文献
976.
977.
Thi Hai Yen Tran Aya Fukuda Shiho Aizawa Phuong Linh Bui Yohei Hayashi Ken Nishimura Koji Hisatake 《Biochemistry and Biophysics Reports》2018
Generation of induced pluripotent stem cells (iPSCs) with naive pluripotency is important for their applications in regenerative medicine. In female iPSCs, acquisition of naive pluripotency is coupled to X chromosome reactivation (XCR) during somatic cell reprogramming, and live cell monitoring of XCR is potentially useful for analyzing how iPSCs acquire naive pluripotency. Here we generated female mouse embryonic stem cells (ESCs) that carry the enhanced green fluorescent protein (EGFP) and humanized Kusabira-Orange (hKO) genes inserted into an intergenic site near either the Syap1 or Taf1 gene on both X chromosomes. The ESC clones, which initially expressed both EGFP and hKO, inactivated one of the fluorescent protein genes upon differentiation, indicating that the EGFP and hKO genes are subject to X chromosome inactivation (XCI). When the derived somatic cells carrying the EGFP gene on the inactive X chromosome (Xi) were reprogrammed into iPSCs, the EGFP gene on the Xi was reactivated when pluripotency marker genes were induced. Thus, the fluorescent protein genes inserted into an intergenic locus on both X chromosomes enable live cell monitoring of XCI during ESC differentiation and XCR during reprogramming. This is the first study that succeeded live cell imaging of XCR during reprogramming. 相似文献
978.
Phosphatidylinositol 4,5-bisphosphate stimulates phosphorylation of the adaptor protein Shc by c-Src 总被引:1,自引:0,他引:1
Ken-ichi Sato Hideki Yamamoto Tetsuji Otsuki Mamoru Aoto Alexander A. Tokmakov Fumio Hayashi Yasuo Fukami 《FEBS letters》1997,410(2-3)
The adaptor protein Shc was prepared as glutathione S-transferase fusion proteins (GST–Shc) and used as in vitro substrate for c-Src. Since phosphotyrosine-binding domain of Shc has been shown to bind phosphatidyl-inositol 4,5-bisphosphate (PtdIns(4,5)P2) [Zhou et al. (1995) Nature 378, 584–592], effect of PtdIns(4,5)P2 on the phosphorylation of GST–Shc by c-Src was examined. PtdIns(4,5)P2 stimulated the phosphorylation of GST–Shc without any effect on the c-Src activity as judged by both its autophosphorylation and phosphorylation of exogenous substrate, Cdc2 peptide. On the other hand, phosphatidylserine, phosphatidic acid, phosphatidylinositol, and phosphatidylinositol 4-phosphate but not phosphatidylcholine stimulated the c-Src activity itself. Km for GST–Shc in the presence of 1 μM PtdIns(4,5)P2 was calculated to be 90 nM. The PtdIns(4,5)P2-dependent phosphorylation of GST–Shc was inhibited by a GST–fusion protein containing the phosphotyrosine-binding domain of Shc. These results suggest that PtdIns(4,5)P2 can act as a regulator of phosphorylation of Shc by c-Src through its binding to Shc. 相似文献
979.
Emiko Isogai Kimiharu Hirose Koichi Kimura Shunji Hayashi Toru Kubota Nobuhiro Fujii Hiroshi Isogai 《Microbiology and immunology》1997,41(3):271-275
Leptospire lipopolysaccharide (LPS) stimulated the adherence of polymorphonuclear neutrophils (PMNs) to human umbilical vein endothelial cells (HUVEC). Enhanced PMN adherence in response to leptospire LPS can be mediated by platelet-activator-factor (PAF), because a PAF antagonist reduced adherence. Leptospire LPS also induced the adherence platelets or U937. The second experiment involved leptospire LPS elicited platelet aggregation in a PMN-platelet mixture, because leptospire LPS stimulated human PMN but not the human platelets. The platelet response was observed only in the mixture system and was inhibited by a PAF antagonist. PAF could be an important pathogenic factor in human leptospirosis. 相似文献
980.
William Ba-Thein Satoko Inui Tohru Shimizu Tint Swe Sayera Banu Kaori Ohtani Misari Oe Naomi Sakurai Shinichi Nakamura Hideo Hayashi 《Microbiology and immunology》1997,41(8):629-631
The genomic structure of the pfoA-colA region in six theta-toxin-deficient strains of Clostridium perfringens was examined by Southern hybridization using the pfoR, pfoA, pbg, arcABDC and colA genes, encoding regulator for pfoA, theta-toxin, beta-galactosidase, arginine metabolism enzymes and kappa-toxin, respectively, as gene probes. It is suggested that the productivity of theta-toxin in these strains is diverse because of the multiple genetic backgrounds including single deletion of pfoA, large deletion of the pfoA-colA region and the putative point mutations. 相似文献