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991.
In this study, the chloroplast genome of Hariotina reticulata was fully sequenced and compared to other Sphaeropleales chloroplast genomes. It is 210,757 bp larger than most Sphaeropleales cpDNAs. It presents a traditional chloroplast structure, and contains 103 genes, including 68 protein-coding genes, six rRNA genes and 29 tRNA genes. The coding region constitutes of 43% of the whole cpDNA. Eighteen introns are found in 11 genes and six introns are unique for Hariotina. 11 open reading frames are identified among these introns. The synteny between Hariotina and Acutodesmus cpDNAs is in general identical, while within Sphaeropleales order, high variability in cpDNA architecture is indicated by general high DCJ distances. Ankyra judayi exhibits the greatest dissimilarity in gene synteny to the others and share some unique gene clusters with Treubaria triappendiculata. The phylogenomic analyses show that A. judayi is clustered with Treubariaceae species and sister to Chlorophyceae incertae sedis and other Sphaeropleales species. The monophyly of Sphaeropleales is rejected. 相似文献
992.
Salidroside attenuates neuroinflammation and improves functional recovery after spinal cord injury through microglia polarization regulation 下载免费PDF全文
Chenggui Wang Qingqing Wang Yiting Lou Jianxiang Xu Zhenhua Feng Yu Chen Qian Tang Gang Zheng Zengjie Zhang Yaosen Wu Naifeng Tian Yifei Zhou Huazi Xu Xiaolei Zhang 《Journal of cellular and molecular medicine》2018,22(2):1148-1166
Spinal cord injury (SCI) is a severe neurological disease; however, few drugs have been proved to treat SCI effectively. Neuroinflammation is the major pathogenesis of SCI secondary injury and considered to be the therapeutic target of SCI. Salidroside (Sal) has been reported to exert anti‐inflammatory effects in airway, adipose and myocardial tissue; however, the role of Sal in SCI therapeutics has not been clarified. In this study, we showed that Sal could improve the functional recovery of spinal cord in rats as revealed by increased BBB locomotor rating scale, angle of incline, and decreased cavity of spinal cord injury and apoptosis of neurons in vivo. Immunofluorescence double staining of microglia marker and M1/M2 marker demonstrated that Sal could suppress M1 microglia polarization and activate M2 microglia polarization in vivo. To verify how Sal exerts its effects on microglia polarization and neuron protection, we performed the mechanism study in vitro in microglia cell line BV‐2 and neuron cell line PC12. The results showed that Sal prevents apoptosis of PC12 cells in coculture with LPS‐induced M1 BV‐2 microglia, also the inflammatory secretion phenotype of M1 BV‐2 microglia was suppressed by Sal, and further studies demonstrated that autophagic flux regulation through AMPK/mTOR pathway was involved in Sal regulated microglia polarization after SCI. Overall, our study illustrated that Sal could promote spinal cord injury functional recovery in rats, and the mechanism may relate to its microglia polarization modulation through AMPK‐/mTOR‐mediated autophagic flux stimulation. 相似文献
993.
本文记述赤眼蜂科Trichogrammatidae斯赤眼蜂属SoikiellaNowicki一新种,亚洲斯赤眼蜂Soikiellaasiaticasp.nov.,新种与S.mongibelli相似,主要区别为:新种为褐色,体长0.9-1.0mm;雌虫触角棒节显著膨大呈卵圆形,长为宽的2倍;前翅翅面纤毛规则排列成行;而后者为黑色,体长1.13mm;棒节较细长,长为宽的2.5倍;前翅翅面仅有13列纤毛排列成行,其余散乱分布;两者易于区别。 相似文献
994.
Enhancement of Neurite Outgrowth Following Calpain Inhibition Is Mediated by Protein Kinase C 总被引:2,自引:0,他引:2
†‡ Thomas B. Shea Corinne M. Cressman §Melissa J. Spencer †Mary Lou Beermann †‡Ralph A. Nixon 《Journal of neurochemistry》1995,65(2):517-527
Abstract: We examined the interdependence of calpain and protein kinase C (PKC) activities on neurite outgrowth in SH-SY-5Y human neuroblastoma cells. SH-SY-5Y cells elaborated neurites when deprived of serum or after a specific thrombin inhibitor, hirudin, was added to serum-containing medium. The extent of neurite outgrowth under these conditions was enhanced by treatment of cells with the cell-permeant cysteine protease inhibitors N-acetyl-leucyl-leucyl-norleucinal (“C1”) and calpeptin or by the phospholipid-mediated intracellular delivery of either a recombinant peptide corresponding to a conserved inhibitory sequence of human calpastatin or a neutralizing anti-calpain antisera. Calpain inhibition in intact cells was confirmed by immunoblot analysis showing inhibition of calpain autolysis and reduced proteolysis of the known calpain substrates fodrin and microtubule-associated protein 1. The above inhibitory peptides and antiserum did not induce neurites in medium containing serum but lacking hirudin, suggesting that increased surface protein adhesiveness is a prerequisite for enhancement of neurite outgrowth by calpain inhibition. Treatment of cells with the PKC inhibitor H7, staurosporine, or sphingosine induced neurite outgrowth independently of serum concentration. Because calpain is thought to regulate PKC activity, we examined this potential interrelationship during neurite outgrowth. Simultaneous treatment with calpain and PKC inhibitors did not produce additive or synergistic effects on neurite outgrowth. PKC activation by 2-O-tetradecanoylphorbol 13-acetate (TPA) prevented and reversed both neurite initiation by serum deprivation and its enhancement by calpain inhibitors. Treatment of cells with the calpain inhibitor C1 retarded PKC down-regulation following TPA treatment. Cell-free analyses demonstrated the relative specificity of various protease and kinase inhibitors for calpain and PKC and confirmed the ability of millimolar calcium-requiring calpain to cleave the SH-SY-5Y PKC regulatory subunit from the catalytic subunit, yielding a free catalytic subunit (protein kinase M). These findings suggest that the influence of PKC on neurite outgrowth is downstream from that of surface adhesiveness and calpain activity. 相似文献
995.
紫云英根瘤菌结瘤因子的初步研究 总被引:7,自引:1,他引:7
最近的研究结果表明,豆科植物与根瘤菌的共生识别是一种双向的信号物质交换过程.首先是豆科植物的根或种子分泌类黄酮物质,诱导根瘤菌的结瘤基因(nod genes)产生结瘤因子(nod factors),分泌到胞外,为植物所接受,从而引发植物某些基因表达,细胞分化,细胞壁形成,最终导致根毛变形等一系列变化.已经测定了几种苜蓿根瘤菌(Rhizobium meliloti)和豌豆根瘤菌(R.leguminosarum bv.viciae)结瘤因子的分子结构式,它们均属于寡糖胺类物质,在没有根瘤菌存在的条件下,结瘤因子能独立地促使根毛发生变形,这是检测结瘤因子是否存在的重要手段,即根毛变形试验(Root hairdeformation assay,简称Had试验).高浓度的结瘤因子甚至能诱导植物产生空瘤,其组织结构与典型的根瘤相同. 相似文献
996.
M Yamashita S Fukada M Yoshikuni P Bulet T Hirai A Yamaguchi Y H Lou Z Zhao Y Nagahama 《Developmental biology》1992,149(1):8-15
Maturation-promoting factor (MPF) activity has been demonstrated for the first time in fish oocytes. We purified MPF from a 100,000g supernatant of crushed, naturally spawned carp oocytes using four chromatography columns: Q-Sepharose Fast-Flow, p13suc1-affinity Sepharose, Mono S, and Superose 12. The final preparation was purified over 1000-fold with a recovery of about 1%. On Superose 12, MPF eluted as a single peak with an apparent molecular weight of 100 kDa. SDS-PAGE analysis of the active fractions after Superose 12 revealed the presence of four proteins of 33, 34, 46, and 48 kDa. A monoclonal antibody against the PSTAIR sequence of cdc2 kinase recognized the 33- and 34-kDa proteins for which the 46- and 48-kDa proteins are endogenous substrates. The 46- and 48-kDa proteins were recognized by a monoclonal antibody against Escherichia coli-produced goldfish cyclin B, but not by an anti-cyclin A antibody. When oocytes were matured in the presence of 32P, the labeling was seen with the 34-kDa protein, but not with the 33-kDa protein. The 34-kDa protein corresponded to the MPF activity, but the 33-kDa protein did not. These findings indicate that carp MPF is a complex of cdc2 kinase and cyclin B, and further that active MPF contains the phosphorylated form of cdc2 kinase. 相似文献
997.
Signaling through CD5 Activates a Pathway Involving Phosphatidylinositol 3-Kinase, Vav, and Rac1 in Human Mature T Lymphocytes 总被引:4,自引:0,他引:4 下载免费PDF全文
Sonja I. Gringhuis Lou F. M. H. de Leij Paul J. Coffer Edo Vellenga 《Molecular and cellular biology》1998,18(3):1725-1735
CD5 acts as a coreceptor on T lymphocytes and plays an important role in T-cell signaling and T-cell–B-cell interactions. Costimulation of T lymphocytes with anti-CD5 antibodies results in an increase of the intracellular Ca2+ levels, and subsequently in the activation of Ca2+/calmodulin-dependent (CaM) kinase type IV. In the present study, we have characterized the initial signaling pathway induced by anti-CD5 costimulation. The activation of phosphatidylinositol (PI) 3-kinase through tyrosine phosphorylation of its p85 subunit is a proximal event in the CD5-signaling pathway and leads to the activation of the lipid kinase activity of the p110 subunit. The PI 3-kinase inhibitors wortmannin and LY294002 inhibit the CD5-induced response as assessed in interleukin-2 (IL-2) secretion experiments. The expression of an inactivated Rac1 mutant (Rac1 · N17) in T lymphocytes transfected with an IL-2 promoter-driven reporter construct also abrogates the response to CD5 costimulation, while the expression of a constitutively active Rac1 mutant (Rac1-V12) completely replaces the CD5 costimulatory signal. The Rac1-specific guanine nucleotide exchange factor Vav is heavily phosphorylated on tyrosine residues upon CD5 costimulation, which is a prerequisite for its activation. A role for Vav in the CD5-induced signaling pathway is further supported by the findings that the expression of a dominant negative Vav mutant (Vav-C) completely abolishes the response to CD5 costimulation while the expression of a constitutively active Vav mutant [Vav(Δ1–65)] makes the CD5 costimulation signal superfluous. Wortmannin is unable to block the Vav(Δ1–65)- or Rac1 · V12-induced signals, indicating that both Vav and Rac1 function downstream from PI 3-kinase. Vav and Rac1 both act upstream from the CD5-induced activation of CaM kinase IV, since KN-62, an inhibitor of CaM kinases, and a dominant negative CaM kinase IV mutant block the Vav(Δ1–65)-and Rac1 · V12-mediated signals. We propose a model for the CD5-induced signaling pathway in which the PI 3-kinase lipid products, together with tyrosine phosphorylation, activate Vav, resulting in the activation of Rac1 by the Vav-mediated exchange of GDP for GTP. 相似文献
998.
谷氨酸对嗜铬细胞瘤细胞热休克蛋白70 mRNA的诱导分析 总被引:2,自引:0,他引:2
热休克反应普遍存在于从细菌到人的整个生物界。除热外,多种应激原都可引起热休克蛋白的诱导。至于神经递质是否能够诱导热休克蛋白的表达,目前并不清楚。本文以诱导型热休克蛋白(hsp)70的cDNA为探针,运用Northern blot的方法,在嗜铬细胞瘤细胞(PC12)上,分析了谷氨酸和乙酰胆碱对hsp70 mRNA的诱导作用。在此基础上又初步分析了起作用的递质受体。结果表明:在一定的浓度(50 ̄500 相似文献
999.
Wrangham Richard W. Conklin-Brittain Nancy Lou Hunt Kevin D. 《International journal of primatology》1998,19(6):949-970
In order to understand dietary differentiation among frugivorous primates with simple stomachs, we present the first comparison of plant diets between chimpanzees and cercopithecine monkeys that controls for food abundance. Our aim was to test the hypothesis that monkeys have a more diverse diet as a result of their dietary tolerance for chemical antifeedants. Our study species are chimpanzees, blue monkeys, redtail monkeys, and gray-cheeked mangabeys living in overlapping ranges in Kibale National Park, Uganda. We indexed food abundance by the percentage of trees having ripe fruit within the range of each group; it varied widely during the year. Chimpanzees spent almost 3 times as much of their feeding time eating ripe fruits as the monkeys did and confined their diets almost exclusively to ripe fruits when they were abundant. Monkeys maintained a diverse diet at all times. When ripe fruit was scarce chimpanzee and monkey diets diverged. Chimpanzees relied on piths as their main fallback food, whereas monkeys turned to unripe fruits and seeds. For each primate group we calculated the total weighted mean intake of 5 antifeedants; condensed tannins (CT), total tannins assayed by radial diffusion (RD), monoterpenoids (MT), triterpenoids (TT), and neutral-detergent fiber (NDF). Monkeys had absolutely higher intakes of CT, RD, MT, and TT than those of chimpanzees, and their intake of NDF did not differ from that of chimpanzees, appearing relatively high given their lower body weights. However contrary to expectation, dietary divergence during fruit scarcity was not associated with any change in absolute or relative intake of antifeedants. For example, fruit scarcity did not affect the relative intake of antifeedants by cercopithecines compared to chimpanzees. Our results establish chimpanzees as ripe-fruit specialists, whereas cercopithecines are generalists with a higher intake of antifeedants. The low representation of ripe fruits in the diets of cercopithecines has not been explained. An important next step is to test the hypothesis that the difference between Kibale chimpanzees and cercopithecines represents a more general difference between apes and monkeys. 相似文献
1000.
IIntroductionTheuseofrestrlctlonfragmentlengthpolymorphism(RFLP)markershasgreatlyslmpllfledthegeneticanalysisofquantitativetraits,providingareliableandextensiveframeworkofquantltatlvemarkerstowhichquantltatlyetyaitIOCI(QTL)clnhilinked[‘].TodetectthelinkagebetwwenRFLPmarkersandPhenotyPlcvariationsoh-served,generallinearmodelofanalysisofvariance(ANOVA)hasbeenextensivelyusedL‘zJ.ByusingF、populations,thecompletegeneticInformation,thatIs,thethreegenotypesofageneticfact… 相似文献