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101.
Murine vasoactive intestinal contractor (VIC) and its human analog endothelin-2 (ET2) are potent vasoactive hormones composed of 21 amino acids. To study the structural characteristics of the VIC/ET2 gene (HGMW-approved symbol EDN2), we isolated the full length of the mouse VIC gene. Sequence analysis indicates that a biologically active mature VIC peptide is produced from a 175-residue precursor protein; preproVIC (PPVIC). Several remarkable similarities of the PPVIC gene to the human preproendothelin-1 gene strongly suggest that the two genes have arisen from a common progenitor by gene duplication. Transfection of ACHN adenocarcinoma cells with the cDNA resulted in the production of VIC peptide. VIC production was increased by the deletion of the 3'-untranslated region, which contains an AU-rich mRNA destabilizing sequence. Increased PPVIC gene expression during the late embryonic stage suggests an important function in development. This study provides the basis for disruption and regulation analysis of the gene, which may lead to a better understanding of VIC/ET2's physiological significance. 相似文献
102.
【目的】抗反转录病毒疗法(ART)能够有效控制人免疫缺陷病毒(Human immunodeficiency virus-1,HIV-1)的复制,但是不能将其完全清除。至2012年底,全球仍有3 500万HIV-1感染者,同年约160万人死于艾滋病(Acquired immune deficiency syndrome,AIDS)及其相关疾病。HIV-1感染难以根治的主要原因之一是机体内HIV-1潜伏储存库(Reservoir)的存在。HIV-1潜伏储存库主要由CD4+T细胞和单核巨噬细胞构成,与CD4+T细胞相比,目前研究者对单核巨噬系细胞中HIV-1病毒复制机制尚不明了,且缺乏适宜的研究体系。因此,为探讨单核细胞活化或分化信号对HIV-1复制的影响,我们建立了旨在研究HIV-1前病毒转录调控机制的人单核巨噬细胞系模型。【方法】构建env区域移码突变和nef区域携带EGFP或Nano Luc报告基因的HIV-1 NLn GFP-Kp或NLn Nano Luc-Kp重组病毒,分别感染2种人单核细胞系THP-1或U937细胞。通过有限稀释法制备单克隆细胞系,利用流式细胞术或Nano Luc荧光素酶活性分析检测报告基因的表达。筛选EGFP或Nano Luc阴性表达的细胞克隆,经激活剂佛波酯(Phorbol-12-myristate-13-acetate,PMA)刺激后鉴定潜伏感染的细胞克隆。【结果】研究中鉴定了4个HIV-1潜伏感染的细胞克隆。其中2个是表达EGFP的THP-1克隆,2个是以Nano Luc为报告基因的U937克隆。这些克隆在PMA刺激处理后皆有报告基因的表达,而在恒态条件下未检测到报告基因的表达。【结论】成功建立了4个HIV-1潜伏感染的人单核细胞系克隆,该模型有助于理解单核巨噬系细胞的HIV-1病毒复制机制,可能成为进一步研究HIV-1前病毒转录调控机制的有力工具。 相似文献
103.
F Furuyama Y Ishida M Furuyama T Hashitani Y Isobe H Sato K Ohara H Nishino 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1989,94(1):133-138
1. The relationship between thermal salivation (TS) and thermoregulation was studied in anesthetized rats. 2. Of the 6 anesthetics used, ketamine-anesthetized rats secreted the largest amount of saliva. Salivation, however, was thermal and not induced by ketamine itself. 3. Ketamine-anesthetized rats readily secreted saliva at core temperatures less than 40 degrees C but TS was remarkably enhanced by hyperthermia of 40-42.5 degrees C. 4. The equilibrium phase in the triphasic heat response of core temperature was a consequence of equilibrium between heat gain and heat loss by salivation. 相似文献
104.
105.
106.
Kyoko Saio Emiko Koyama Tokuji Watanabe 《Bioscience, biotechnology, and biochemistry》2013,77(10):1195-1200
This paper constitutes the first report in a research series undertaken in order to clarify the interactive relationships among soybean meal protein, calcium and phytic acid in solution and in precipitate.Data presented are mainly concerned with solubility characteristics of soybean meal proteins as a function of pH. The results support the suggestion as follows; phosphorus and calcium give the remarkable effects on solubility characteristics of protein, the complex containing protein, calcium and phosphorus is formed above isoelectric point of protein and the combinations are labile above at pH 8, especially by heating. 相似文献
107.
Suzuki Setsuko Kyoko Sugai Ichiro Tamaki Koji Takayama Hidetoshi Kato Hiroshi Yoshimaru 《Molecular ecology》2020,29(6):1050-1068
Pandanus boninensis, endemic to the Ogasawara Islands, Japan, is distributed on both the older Bonin and younger Volcano Islands. In this study, we conducted population genetic analyses of P. boninensis on these islands to examine the population diversity and structure across old and young islands, to assess potential differences in population demography with island age, and to collect any evidence of migration between old and young islands. We found that the genetic diversity of expressed sequence tag (EST)–based microsatellite (SSR) markers, the nucleotide diversity of nuclear DNA sequences, and the haplotype diversity of chloroplast DNA on young islands were lower than those on old islands. Clustering analyses of EST‐SSR indicated that populations on old islands were strongly diverged from those on young islands. Approximate Bayesian computation analysis of EST‐SSR suggested that population expansion occurred on old islands while population reduction occurred on young islands. We also found evidence of migration among old islands (mostly from south to north), while it appears that there have been very few migration events between old and young islands. These differences could be due to the fact that young islands tend to be geographically isolated and support smaller populations that began a shorter time ago from limited founders. The P. boninensis populations on the Volcano Islands are interesting from an evolutionary perspective as they constitute a classic example of the early stages of progressive colonization on oceanic islands with small effective population sizes and low genetic diversity. 相似文献
108.
Aida Rieko Hagiwara Keitaro Okano Kazunori Nakata Kyoko Obata Yuho Yamashita Takahiro Yoshida Kaoru Hagiwara Hiromi 《Molecular biology reports》2021,48(3):2291-2297
Molecular Biology Reports - Apigenin is a flavonoid with antioxidant and anticancer effects. It has been reported that apigenin inhibits proliferation, migration, and invasion and induces apoptosis... 相似文献
109.
Takuya Kobayashi Yamato Ishida Tomoaki Hirano Yohei Katoh Kazuhisa Nakayama 《Molecular biology of the cell》2021,32(1):45
Cilia sense and transduce extracellular signals via specific receptors. The intraflagellar transport (IFT) machinery mediates not only bidirectional protein trafficking within cilia but also the import/export of ciliary proteins across the ciliary gate. The IFT machinery is known to comprise two multisubunit complexes, namely, IFT-A and IFT-B; however, little is known about how the two complexes cooperate to mediate ciliary protein trafficking. We here show that IFT144–IFT122 from IFT-A and IFT88–IFT52 from IFT-B make major contributions to the interface between the two complexes. Exogenous expression of the IFT88(Δα) mutant, which has decreased binding to IFT-A, partially restores the ciliogenesis defect of IFT88-knockout (KO) cells. However, IFT88(Δα)-expressing IFT88-KO cells demonstrate a defect in IFT-A entry into cilia, aberrant accumulation of IFT-B proteins at the bulged ciliary tips, and impaired import of ciliary G protein–coupled receptors (GPCRs). Furthermore, overaccumulated IFT proteins at the bulged tips appeared to be released as extracellular vesicles. These phenotypes of IFT88(Δα)-expressing IFT88-KO cells resembled those of IFT144-KO cells. These observations together indicate that the IFT-A complex cooperates with the IFT-B complex to mediate the ciliary entry of GPCRs as well as retrograde trafficking of the IFT machinery from the ciliary tip. 相似文献