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Sera Toshihiro Kobayashi Hiroaki Hoshino Masato Uesugi Kentaro Matsumoto Takeshi Tanaka Masao 《Biomechanics and modeling in mechanobiology》2019,18(2):375-385
Biomechanics and Modeling in Mechanobiology - In this study, based on the measurements of intracortical vascular canal structure, we investigated the disuse effect on local O2 supply in the... 相似文献
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采用蔗糖密度离心方法分离完整叶绿体,进一步分离叶绿体被膜,借助SDS-PAGE分析了2种油菜叶绿体被膜的蛋白组分.用对拟南芥叶绿体外被膜上存在Toc33的特异抗体,检测到油菜叶绿体被膜上存在Toc33转运蛋白.Toc33在2种油菜中的相对含量不同,黄化油菜叶绿体被膜中高于野生油菜叶绿体被膜. 相似文献
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Masato Nagaoka Motohiro Kobayashi Chie Kawai Sunil K. Mallanna Stephen A. Duncan 《PloS one》2015,10(8)
Maintenance and differentiation of human pluripotent stem cells (hPSCs) usually requires culture on a substrate for cell adhesion. A commonly used substratum is Matrigel purified from Engelbreth—Holm—Swarm sarcoma cells, and consists of a complex mixture of extracellular matrix proteins, proteoglycans, and growth factors. Several studies have successfully induced differentiation of hepatocyte-like cells from hPSCs. However, most of these studies have used Matrigel as a cell adhesion substrate, which is not a defined culture condition. In an attempt to generate a substratum that supports undifferentiated properties and differentiation into hepatic lineage cells, we designed novel substrates consisting of vitronectin fragments fused to the IgG Fc domain. hPSCs adhered to these substrates via interactions between integrins and the RGD (Arg-Gly-Asp) motif, and the cells maintained their undifferentiated phenotypes. Using a previously established differentiation protocol, hPSCs were efficiently differentiated into mesendodermal and hepatic lineage cells on a vitronectin fragment-containing substrate. We found that full-length vitronectin did not support stable cell adhesion during the specification stage. Furthermore, the vitronectin fragment with the minimal RGD-containing domain was sufficient for differentiation of human induced pluripotent stem cells into hepatic lineage cells under completely defined conditions that facilitate the clinical application of cells differentiated from hPSCs. 相似文献
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Studies of eco-evolutionary dynamics have integrated evolution with ecological processes at multiple scales (populations, communities and ecosystems) and with multiple interspecific interactions (antagonistic, mutualistic and competitive). However, evolution has often been conceptualised as a simple process: short-term directional adaptation that increases population growth. Here we argue that diverse other evolutionary processes, well studied in population genetics and evolutionary ecology, should also be considered to explore the full spectrum of feedback between ecological and evolutionary processes. Relevant but underappreciated processes include (1) drift and mutation, (2) disruptive selection causing lineage diversification or speciation reversal and (3) evolution driven by relative fitness differences that may decrease population growth. Because eco-evolutionary dynamics have often been studied by population and community ecologists, it will be important to incorporate a variety of concepts in population genetics and evolutionary ecology to better understand and predict eco-evolutionary dynamics in nature. 相似文献
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MASCOT: multiple alignment system for protein sequences based on three-way dynamic programming 总被引:5,自引:0,他引:5
Hirosawa Makoto; Hoshida Masaki; Ishikawa Masato; Toya Tomoyuki 《Bioinformatics (Oxford, England)》1993,9(2):161-167
A multiple alignment methodology that can produce high-qualityalignment is extremely important for predicting the structureof unknown proteins. Nearly all the methodologies developedso far have employed two-way alignment only. Although thesemethods are fast, the alignments they produce lose reliabilityas the similarity of sequences reduces. We developed the MASCOTmultiple alignment system. MASCOT can sustain the reliabilityof alignment even when the similarity of sequences is low. MASCOTachieves high-quality alignment by employing three-way alignmentin addition to two-way alignment. The resultant alignments arerefined by simulated annealing to higher quality. We also usea cluster analysis of sequences to produce highly reliable alignments. 相似文献
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Toshihiro Ohura Masato Ogasawara Hiroyuki Ikeda Kuniaki Narisawa Keiya Tada 《Human genetics》1993,92(4):397-402
Propionic acidemia is an autosomal recessive metabolic disease resulting from a deficiency of propionyl CoA carboxylase (PCC) activity. To investigate the genetic basis of propionic acidemia, we isolated a cDNA encoding the precursor of the subunit of human PCC ( PCC). The cloned cDNA sequence was 1,832 bp long and the open reading frame of 1,617 nucleotides encoded a polypeptide of 539 amino acids with a molecular mass of 58,202 Da. The human PCC sequence shared a high degree of homology (91%) with the full-length cDNA of rat PCC at the amino acid level; there were only 47 differences among 539 amino acid residues compared. Polymerase chain reaction amplification and sequencing of cDNA from a subunit-deficient Japanese patient revealed a deletion of 101 nucleotides consisting of one exon from mature mRNA. This deletion resulted in a frameshift and a stop codon in the new frame. Analysis of the genomic DNA revealed a homozygous 8-bp deletion from bp3 to bp10 of the intron just downstream of the deleted exon. This deletion disrupted the consensus 5 splice signal and led to exon skipping. 相似文献
1000.
The possible involvement of protein phosphatase 1 in thrombin-induced Ca2+ influx of human platelets
Kouhei Murata Masato Sakon Jun-Ichi Kambayashi Masao Yukawa Yoshiko Yano Kazumasa Fujitani Tomio Kawasaki Eiichi Shiba Takesada Mori 《Journal of cellular biochemistry》1993,51(4):442-445
Protein phosphatase 1 is considered to be involved in thrombin-induced platelet activation (Murata et al., Biochem Int 26:327–334, 1992). To clarify the mechanism, we examined the effects of protein phosphatase 1 and 2A inhibitors (calyculin A, tautomycin, okadaic acid) on Ca2+ influx. In the presence of 1 mM Ca2+, thrombin- (0.1 U/ml) induced platelet aggregation and ATP release were inhibited by calyculin A, while this inhibitory effect was abolished in the absence of Ca2+ (EGTA 1 mM). Furthermore, thrombin-induced Mn2+ influx but not intracellular Ca2+ mobilization was inhibited by calyculin A in a dose-related manner. Calyculin A also blocked the ongoing Ca2+ influx when added 3 min after thrombin stimulation. Similar inhibitory effects were observed with okadaic acid and tautomycin in the same potency sequence as the reported one for protein phosphatase 1 (calyculin A > tautomycin > okadaic acid). These results suggest that the anti-platelet effects of phosphatase inhibitors are due to the inhibition of Ca2+ influx and that protein phosphatase 1 plays a key role in the regulation of receptor operated Ca2+ channel of human platelets. 相似文献