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31.
Atsushi Kawakami Takashi Kitsukawa Shin Takagi Hajime Fujisawa 《Developmental neurobiology》1996,29(1):1-17
Neuropilin (previously A5) is a cell surface glycoprotein that was originally identified in Xenopus tadpole nervous tissues. In Xenopus, neuropilin is expressed on both the presynaptic and postsynaptic elements in the visual and general somatic sensory systems, suggesting a role in neuronal cell recognition. In this study, we identified a mouse homologue of neuropilin and examined its expression in developing mouse nervous tissues. cDNA cloning and sequencing revealed that the primary structure of the mouse neuropilin was highly similar to that of Xenopus and that the extracellular segment of the molecule possessed several motifs that were expected to be involved in cell-cell interaction. Immunohistochemistry and in situ hybridization analyses in mice indicated that the expression of neuropilin was restricted to particular neuron circuits. Neuropilin protein was localized on axons but not on the somata of neurons. The expression of neuropilin persisted through the time when axons were actively growing to form neuronal connections. These observations suggest that neuropilin is involved in growth, fasciculation, and targeting for a particular groups of axons. © 1996 John Wiley & Sons, Inc. 相似文献
32.
Oda A Wada I Miura K Okawa K Kadoya T Kato T Nishihara H Maeda M Tanaka S Nagashima K Nishitani C Matsuno K Ishino M Machesky LM Fujita H Randazzo P 《The Journal of biological chemistry》2003,278(8):6456-6460
Searching for proteins in platelets that can interact with the N-terminal SH3 domain of CrkL (using a combination of a pull-down assay followed by mass spectrometry), we have found that human platelets express an ADP-ribosylation factor (Arf)-specific GTPase-activating protein (GAP), ASAP1, as a CrkL-binding protein. In spreading platelets, most endogenous ASAP1 is localized at peripheral focal adhesions. To determine the physiologic significance of the CrkL-ASAP1 association, we overexpressed CrkL, ASAP1, or both in combination in COS7 cells. Unlike endogenous ASAP1 in platelets, overexpressed ASAP1 showed diffuse cytoplasmic distribution. However, when co-expressed with wild-type CrkL, both endogenous and expressed ASAP1 accumulated at CrkL-induced focal adhesions. An SH2-mutated CrkL, which cannot localize at focal adhesions, failed to recruit ASAP1 into focal adhesions. Thus, CrkL appears to be a lynchpin between ASAP1 and peripheral focal adhesions. 相似文献
33.
Satoshi N. Suzuki Masae I. Ishihara Masahiro Nakamura Shin Abe Tsutom Hiura Kosuke Homma Motoki Higa Daisuke Hoshino Kazuhiko Hoshizaki Hideyuki Ida Ken Ishida Motohiro Kawanishi Kazutaka Kobayashi Koichiro Kuraji Shigeo Kuramoto Takashi Masaki Kaoru Niiyama Mahoko Noguchi Haruto Nomiya Satoshi Saito Takeshi Sakai Michinori Sakimoto Hitoshi Sakio Tamotsu Sato Hirofumi Shibano Mitsue Shibata Maki Suzuki Atsushi Takashima Hiroshi Tanaka Masahiro Takagi Naoaki Tashiro Naoko Tokuchi Toshiya Yoshida Yumiko Yoshida 《Ecological Research》2012,27(6):989-990
This data paper reports litter fall data collected in a network of 21 forest sites in Japan. This is the largest litter fall data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Twenty-three permanent plots in which usually 25 litter traps were installed were established in old-growth or secondary natural forests. Litter falls were collected monthly from 2004, and sorted into leaves, branches, reproductive structures and miscellaneous. The data provide seasonal patterns and inter-annual dynamics of litter falls, and their geographical patterns, and offer good opportunities for meta-analyses and comparative studies among forests. 相似文献
34.
Seinen Chow Yoshikazu Kajigaya Hiroaki Kurogi Kentaro Niwa Takuro Shibuno Atsushi Nanami Setuo Kiyomoto 《PloS one》2014,9(7)
Four long-spined sea urchin species in the genus Diadema are known to occur around the Japanese Archipelago. Three species (D. savignyi, D. setosum, and D. paucispinum) are widely distributed in the Indo-Pacific Ocean. The fourth species was detected by DNA analysis among samples originally collected as D. savignyi or D. setosum in Japan and the Marshall Islands and tentatively designated as Diadema -sp, remaining an undescribed species. We analyzed nucleotide sequences of the cytochrome oxidase I (COI) gene in the “D. savignyi-like” samples, and found all 17 individuals collected in the mainland of Japan (Sagami Bay and Kyushu) to be Diadema-sp, but all nine in the Ryukyu Archipelago (Okinawa and Ishigaki Islands) to be D. savignyi, with large nucleotide sequence difference between them (11.0%±1.7 SE). Diadema-sp and D. savignyi shared Y-shaped blue lines of iridophores along the interambulacrals, but individuals of Diadema-sp typically exhibited a conspicuous white streak at the fork of the Y-shaped blue iridophore lines, while this feature was absent in D. savignyi. Also, the central axis of the Y-shaped blue lines of iridophores was approximately twice as long as the V-component in D. savignyi whereas it was of similar length in Diadema-sp. Two parallel lines were observed to constitute the central axis of the Y-shaped blue lines in both species, but these were considerably narrower in Diadema-sp. Despite marked morphological and genetic differences, it appears that Diadema-sp has been mis-identified as D. savignyi for more than half a century. 相似文献
35.
36.
NirD is part of the nitrite reductase complex NirBD that catalyses the reduction of nitrite to NH3 in nitrate assimilation and anaerobic respiration. The crystal structure analysis of NirD from Mycobacterium tuberculosis shows a double β‐sandwich fold. NirD is related in three‐dimensional structure and sequence to the Rieske proteins; however, it does not contain any Fe–S cluster or other cofactors that might be involved in electron transfer. A cysteine residue at the protein surface, conserved in NirD homologues lacking the iron–sulfur cluster might be important for the interaction with NirB and possibly stabilize one of the Fe–S centers in this subunit. Proteins 2012. © 2012 Wiley Periodicals, Inc. 相似文献
37.
Different contributions of local‐ and distant‐regulatory changes to transcriptome divergence between stickleback ecotypes 下载免费PDF全文
38.
Makino N Toyofuku T Takegahara N Takamatsu H Okuno T Nakagawa Y Kang S Nojima S Hori M Kikutani H Kumanogoh A 《FEBS letters》2008,582(28):3935-3940
Dilated cardiomyopathy often results from autoimmunity triggered by microbial infections during myocarditis. However, it remains unclear how immunological disorders are implicated in pathogenesis of autoimmune myocarditis. Here, we demonstrated that Sema4A, a class IV semaphorin, plays key roles in experimental autoimmune myocarditis (EAM). Dendritic cells pulsed with myosin heavy chain-α peptides induced severe myocarditis in wild-type mice, but not in Sema4A-deficient mice. In adoptive transfer experiments, CD4+ T-cells from wild-type mice induced severe myocarditis, while CD4+ T-cells from Sema4A-deficient mice exhibited considerably attenuated myocarditis. Our results indicated that Sema4A is critically involved in EAM by regulating differentiation of T-cells. 相似文献
39.
Yamasaki Masanori Yoshimura Atsushi Yasui Hideshi 《Molecular breeding : new strategies in plant improvement》2003,12(2):133-143
Rice (Oryza sativa L.) ovicidal response to the whitebacked planthopper (Sogatella furcifera Horváth) is characterized by formation of watery lesions and production of an ovicidal substance benzyl benzoate, which results in high egg mortality of whitebacked planthopper. A gene with ovicidal activity to whitebacked planthopper, designated Ovc, and four ovicidal quantitative trait loci (QTLs), qOVA-1-3, qOVA-4, qOVA-5-1 and qOVA-5-2 were identified using near isogenic lines with reciprocal genetic backgrounds of a non-ovicidal Indica variety IR24 and an ovicidal Japonica variety Asominori. Ovc and the four QTLs were mapped on chromosomes 6, 1, 4, 5 and 5, respectively. Ovc is the first gene identified that kills insect eggs in plants. The Asominori allele at Ovc was essential for increasing egg mortality and responsible for production of benzyl benzoate and formation of watery lesions. The Asominori alleles at qOVA-1-3, qOVA-5-1 and qOVA-5-2 increased egg mortality in the presence of Ovc. In contrast, the Asominori allele at qOVA-4 suppressed egg mortality, indicating that qOVA-4 caused transgressive segregation for egg mortality. It was concluded that Ovc and four ovicidal QTLs accounted for the majority of the phenotypic variance for the ovicidal response to whitebacked planthopper in Asominori. 相似文献
40.
Aerobic exercise training reduces plasma endothelin-1 concentration in older women. 总被引:10,自引:0,他引:10
Seiji Maeda Takumi Tanabe Takashi Miyauchi Takeshi Otsuki Jun Sugawara Motoyuki Iemitsu Shinya Kuno Ryuichi Ajisaka Iwao Yamaguchi Mitsuo Matsuda 《Journal of applied physiology》2003,95(1):336-341
Endothelial function deteriorates with aging. On the other hand, exercise training improves the function of vascular endothelial cells. Endothelin-1 (ET-1), which is produced by vascular endothelial cells, has potent constrictor and proliferative activity in vascular smooth muscle cells and, therefore, has been implicated in regulation of vascular tonus and progression of atherosclerosis. We previously reported significantly higher plasma ET-1 concentration in middle-aged than in young humans, and recently we showed that plasma ET-1 concentration was significantly decreased by aerobic exercise training in healthy young humans. We hypothesized that plasma ET-1 concentration increases with age, even in healthy adults, and that lifestyle modification (i.e., exercise) can reduce plasma ET-1 concentration in previously sedentary older adults. We measured plasma ET-1 concentration in healthy young women (21-28 yr old), healthy middle-aged women (31-47 yr old), and healthy older women (61-69 yr old). The plasma level of ET-1 significantly increased with aging (1.02 +/- 0.08, 1.33 +/- 0.11, and 2.90 +/- 0.20 pg/ml in young, middle-aged, and older women, respectively). Thus plasma ET-1 concentration was markedly higher in healthy older women than in healthy young or middle-aged women (by approximately 3- and 2-fold, respectively). In healthy older women, we also measured plasma ET-1 concentration after 3 mo of aerobic exercise (cycling on a leg ergometer at 80% of ventilatory threshold for 30 min, 5 days/wk). Regular exercise significantly decreased plasma ET-1 concentration in the healthy older women (2.22 +/- 0.16 pg/ml, P < 0.01) and also significantly reduced their blood pressure. The present study suggests that regular aerobic-endurance exercise reduces plasma ET-1 concentration in older humans, and this reduction in plasma ET-1 concentration may have beneficial effects on the cardiovascular system (i.e., prevention of progression of hypertension and/or atherosclerosis by endogenous ET-1). 相似文献