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141.
Sphingosine-1-phosphate (S1P) is considered to be an important regulator of diverse biological processes acting as a natural ligand to EDG receptors. As a preliminary study to develop potent and selective agonist and antagonist for EDG receptors, we report synthesis of S1P stereoisomers and analogues and their binding affinities to EDG-1, -3, and -5. 相似文献
142.
RhoA-Binding Kinase α Translocation Is Facilitated by the Collapse of the Vimentin Intermediate Filament Network 下载免费PDF全文
Wun-Chey Sin Xiang-Qun Chen Thomas Leung Louis Lim 《Molecular and cellular biology》1998,18(11):6325-6339
The regulation of morphological changes in eukaryotic cells is a complex process involving major components of the cytoskeleton including actin microfilaments, microtubules, and intermediate filaments (IFs). The putative effector of RhoA, RhoA-binding kinase α (ROKα), is a serine/threonine kinase that has been implicated in the reorganization of actin filaments and in myosin contractility. Here, we show that ROKα also directly affects the structural integrity of IFs. Overexpression of active ROKα, like that of RhoA, caused the collapse of filamentous vimentin, a type III IF. A RhoA-binding-deficient, kinase-inactive ROKα inhibited the collapse of vimentin IFs induced by RhoA in HeLa cells. In vitro, ROKα bound and phosphorylated vimentin at its head-rod domain, thereby inhibiting the assembly of vimentin. ROKα colocalized predominantly with the filamentous vimentin network, which remained intact in serum-starved cells. Treatment of cells with vinblastine, a microtubule-disrupting agent, also resulted in filamentous vimentin collapse and concomitant ROKα translocation to the cell periphery. ROKα translocation did not occur when the vimentin network remained intact in vinblastine-treated cells at 4°C or in the presence of the dominant-negative RhoAN19 mutant. Transient translocation of ROKα was also observed in cells subjected to heat shock, which caused the disassembly of the vimentin network. Thus, the translocation of ROKα to the cell periphery upon overexpression of RhoAV14 or growth factor treatment is associated with disassembly of vimentin IFs. These results indicate that Rho effectors known to act on microfilaments may be involved in regulating the assembly of IFs. Vimentin when phosphorylated also exhibits reduced affinity for the inactive ROKα. The translocation of ROKα from IFs to the cell periphery upon action by activated RhoA and ROKα suggests that ROKα may initiate its own cascade of activation. 相似文献
143.
Ubiquitin-conjugating enzymes (UBE2s or E2s) are characterized by the presence of a highly conserved ubiquitin-conjugating (UBC) domain, which predominantly determines the type of ubiquitin chains and directly controls the cellular fate of the substrate. In this study, an E2 homolog was identified and functionally characterized in abalone, which we named ab-UBE2D. The full-length cDNA consists of 1005 bp with an ORF encoding a protein of 147 amino acids. The deduced amino acid sequence shows ab-UBE2D shares conserved UBC domain with other E2 proteins and belongs to class I E2 enzyme family, which are further confirmed by phylogenetic tree analysis. Real-time PCR and western blot analyses showed that ab-UBE2D was ubiquitously expressed in abalone and the expression level of ab-UBE2d was significantly induced by LPS and Poly (I:C). Immunofluorescence microscopy staining demonstrated that native ab-UBE2D was mainly distributed in the cytoplast. Ubiquitination assay showed that ab-UBE2D had ubiquitin conjugating activity to form the enzyme-(Ub)n conjugates. Taken together, these results strongly suggest that ab-UBE2D is an E2 homolog and it may be involved in the immune response of abalone, Haliotis diversicolor supertexta. 相似文献
144.
Chemokine-like factor 1 (CKLF1) is a cytokine with chemotactic effects on leukocytes and a functional ligand of CCR4. This cytokine is widely expressed and the level of expression is reported to be upregulated in asthma and rheumatoid arthritis (RA), disease conditions in which T lymphocytes are over-activated. In order to determine the expression profile of CKLF1 in activated T lymphocytes, we first employed a PCR-based method on human blood fractions cDNA panels and found that CKLF1 was upregulated in activated CD4+ and CD8+ cells, with no obvious changes in CD19+ cells. We further performed kinetic analyses of CKLF1 expression in phytohemagglutinin (PHA)-stimulated human peripheral blood lymphocytes (PBL) at both the mRNA and protein levels. In resting PBL, the constitutive expression of CKLF1 was low at mRNA level and barely detectable at the protein level; however, both were remarkably upregulated by PHA, appearing at 8h after PHA-stimulation and persisting up to 72h. These results suggest that CKLF1 may be involved in T lymphocyte activation and further study of CKLF1 function will prove valuable. 相似文献
145.
Gallaecimonas xiamenensis 3-C-1T was isolated from a crude-oil-degrading consortium enriched from the surface seawater around Xiamen Island. Here, we present the draft genome of strain 3-C-1T, which contains 4,062,282 bp with a G+C content of 60.58% and contains 3,798 protein-coding genes and 65 tRNAs. 相似文献
146.
Hye Ran Park Jae Meen Lee Gwanhee Ehm Hui-Jun Yang In Ho Song Yong Hoon Lim Mi-Ryoung Kim Keyoung Ran Kim Woong-Woo Lee Young Eun Kim Jae Ha Hwang Chae Won Shin Hyeyoung Park Jin Wook Kim Han-Joon Kim Cheolyoung Kim Dong Gyu Kim Beom Seok Jeon Sun Ha Paek 《PloS one》2016,11(1)
Background
GPi (Internal globus pallidus) DBS (deep brain stimulation) is recognized as a safe, reliable, reversible and adjustable treatment in patients with medically refractory dystonia.Objectives
This report describes the long-term clinical outcome of 36 patients implanted with GPi DBS at the Neurosurgery Department of Seoul National University Hospital.Methods
Nine patients with a known genetic cause, 12 patients with acquired dystonia, and 15 patients with isolated dystonia without a known genetic cause were included. When categorized by phenomenology, 29 patients had generalized, 5 patients had segmental, and 2 patients had multifocal dystonia. Patients were assessed preoperatively and at defined follow-up examinations postoperatively, using the Burke-Fahn-Marsden dystonia rating scale (BFMDRS) for movement and functional disability assessment. The mean follow-up duration was 47 months (range, 12–84)Results
The mean movement scores significantly decreased from 44.88 points preoperatively to 26.45 points at 60-month follow up (N = 19, P = 0.006). The mean disability score was also decreased over time, from 11.54 points preoperatively to 8.26 points at 60-month follow up, despite no statistical significance (N = 19, P = 0.073). When analyzed the movement and disability improvement rates at 12-month follow up point, no significant difference was noted according to etiology, disease duration, age at surgery, age of onset, and phenomenology. However, the patients with DYT-1 dystonia and isolated dystonia without a known genetic cause showed marked improvement.Conclusions
GPi DBS is a safe and efficient therapeutic method for treatment of dystonia patients to improve both movement and disability. However, this study has some limitations caused by the retrospective design with small sample size in a single-center. 相似文献147.
Cho Y Shin YH Kim Y Kim H Lee Y Park E Fuchs JA Lim C 《Biochimica et biophysica acta》2001,1518(1-2):194-199
A cDNA coding thioredoxin (TRX) was isolated from a cDNA library of Schizosaccharomyces pombe by colony hybridization. The 438 bp EcoRI fragment, which was detected by Southern hybridization, reveals an open reading frame which encodes a protein of 103 amino acids. The genomic DNA encoding TRX was also isolated from S. pombe chromosomal DNA using PCR. The cloned sequence contains 1795 bp and encodes a protein of 103 amino acids. However, the C-terminal region obtained from the cDNA clone is -Val-Arg-Leu-Asn-Arg-Ser-Leu, whereas the C-terminal region deduced from the genomic DNA appears to contain -Ala-Ser-Ile-Lys-Ala-Asn-Leu. This indicates that S. pombe cells contain two kinds of TRX genes which have dissimilar amino acid sequences only at the C-terminal regions. The heterologous TRX 1C produced from the cDNA clone could be used as a subunit of T7 DNA polymerase, while the TRX 1G from the genomic DNA could not. The upstream sequence and the region encoding the N-terminal 18 amino acids of the genomic DNA were fused into the promoterless beta-galactosidase gene of the shuttle vector YEp357 to generate the fusion plasmid pYKT24. Synthesis of beta-galactosidase from the fusion plasmid was found to be enhanced by hydrogen peroxide, menadione and aluminum chloride. It indicates that the expression of the cloned TRX gene is induced by oxidative stress. 相似文献
148.
149.
Yuan Xu Chen Shao Xinpeng Fan Alan Warren Khaled A. S. Al-Rasheid Weibo Song Norbert Wilbert 《Polar Biology》2016,39(8):1439-1453
Antarctica is a remote and isolated biotope which makes it an ideal location for studying new and endemic species. Since there is little literature available on the diversity of ciliates in this area, a taxonomic survey of ciliates from melt-water of Collins glacier, King George Island, was carried out from January to March 2006. As a result, the morphology and infraciliature of five ciliates, including one new species, are described using live observations and silver staining: Gastronauta multistriata nov. spec., Neokeronopsis asiatica Foissner et al., 2010, Paraholosticha muscicola Kahl, 1932, Oxytricha sp., and Cyclidium glaucoma Müller, 1786. Gastronauta multistriata nov. spec. is distinguished from its congeners by the following combination of characters: cell size in vivo on average 80 × 40 μm; 5–9 kineties in left ciliary field; 18–23 kineties in right ciliary field, including 10–12 postoral kineties; 7–10 preoral kineties; dorsal brush along anterior dorsal margin, consisting of 5–8 groups of basal bodies. The only minor differences between the current population of N. asiatica and a previously described Antarctic population are the numbers of caudal cirri (6–10 vs. 8–15) and dorsal kineties (11–13 vs. 12–18). Paraholosticha sterkii is synonymised with P. muscicola. The Antarctic population of C. glaucoma corresponds well with a former population from China, the only difference being the number of kinetids in SK n (11–17 vs. 9–11). This work will contribute to the understanding of ciliate diversity in this little studied area. 相似文献
150.
蜜蜂ApismekiferaL .是典型的社会性昆虫 ,蜂王和工蜂都是由受精卵发育而来的二倍体成蜂 ,但是在形态、生理、行为等方面有明显的差异 ,属于不同的级型。蜂王和工蜂的级型分化的关键时期发生在幼虫的 4龄末至 5龄止。分化是由分化基因调控的 ,幼虫期食物的质和量是分化的外部决定因子。JH对两级型中卵巢的分化有非常重要的调控作用。蜜蜂脑或其它组织中可能有分泌调控CA的咽侧体调节激素 ,它们通过对CA中JH的合成和分泌的调控而参与了分化的调控。章鱼胺等生物胺也参与了分化调控过程。 相似文献