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61.
Atul Kakrana Reza Hammond Parth Patel Mayumi Nakano Blake C. Meyers 《Nucleic acids research》2014,42(18):e139
Parallel analysis of RNA ends (PARE) is a technique utilizing high-throughput sequencing to profile uncapped, mRNA cleavage or decay products on a genome-wide basis. Tools currently available to validate miRNA targets using PARE data employ only annotated genes, whereas important targets may be found in unannotated genomic regions. To handle such cases and to scale to the growing availability of PARE data and genomes, we developed a new tool, ‘sPARTA’ (small RNA-PARE target analyzer) that utilizes a built-in, plant-focused target prediction module (aka ‘miRferno’). sPARTA not only exhibits an unprecedented gain in speed but also it shows greater predictive power by validating more targets, compared to a popular alternative. In addition, the novel ‘seed-free’ mode, optimized to find targets irrespective of complementarity in the seed-region, identifies novel intergenic targets. To fully capitalize on the novelty and strengths of sPARTA, we developed a web resource, ‘comPARE’, for plant miRNA target analysis; this facilitates the systematic identification and analysis of miRNA-target interactions across multiple species, integrated with visualization tools. This collation of high-throughput small RNA and PARE datasets from different genomes further facilitates re-evaluation of existing miRNA annotations, resulting in a ‘cleaner’ set of microRNAs. 相似文献
62.
Oocyte formation by mitotically active germ cells purified from ovaries of reproductive-age women 总被引:1,自引:0,他引:1
Germline stem cells that produce oocytes in vitro and fertilization-competent eggs in vivo have been identified in and isolated from adult mouse ovaries. Here we describe and validate a fluorescence-activated cell sorting-based protocol that can be used with adult mouse ovaries and human ovarian cortical tissue to purify rare mitotically active cells that have a gene expression profile that is consistent with primitive germ cells. Once established in vitro, these cells can be expanded for months and can spontaneously generate 35- to 50-μm oocytes, as determined by morphology, gene expression and haploid (1n) status. Injection of the human germline cells, engineered to stably express GFP, into human ovarian cortical biopsies leads to formation of follicles containing GFP-positive oocytes 1-2 weeks after xenotransplantation into immunodeficient female mice. Thus, ovaries of reproductive-age women, similar to adult mice, possess rare mitotically active germ cells that can be propagated in vitro as well as generate oocytes in vitro and in vivo. 相似文献
63.
Y Nakano Y Sugita Y Ishikawa N H Choi T Tobe M Tomita 《Biochimica et biophysica acta》1991,1074(2):326-330
Decay-accelerating factor (DAF) was purified from human pooled urine by conventional techniques. The urine DAF was separated into two peaks, pool I and pool II, by gel chromatography. DAF-U1 was isolated from pool I by hydrophobic chromatography, and DAF-U2 from pool II by anti-DAF IgG column. The specific activities of DAF-U1 and DAF-U2 to decay membrane-phase C5 convertase were about 3% and 70% of membrane form DAF, respectively. However, both urine DAFs revealed a similar activity to each other and slightly higher activity than that of membrane form DAF in decay-accelerating fluid-phase C3 convertase of the alternative pathway. 相似文献
64.
Yoshihara K Ikenouchi J Izumi Y Akashi M Tsukita S Furuse M 《Experimental cell research》2011,(4):413-422
Mammalian ortholog of Scribble tumor suppressor has been reported to regulate cadherin-mediated epithelial cell adhesion by stabilizing the coupling of E-cadherin with catenins, but the molecular mechanism involved remains unknown. In this study, we investigated the relationship between the localization of mouse Scribble at cadherin-based adherens junctions (AJs) and its phosphorylation state. Immunofluorescence staining confirmed that Scribble was localized at AJs as well as at the basolateral plasma membrane in epithelial cells. We found that Scribble was detected as two bands by Western blotting analysis and that the band shift to the higher molecular weight was dependent on its phosphorylation at Ser 1601. Triton X-100 treatment extracted Scribble localized on the basolateral membrane but not Scribble localized at AJs in cultured epithelial cells, and the Triton X-100-resistant Scribble was the Ser 1601-unphosphorylated form. Conversely, an in-house-generated antibody that predominantly recognized Ser 1601-phosphorylated Scribble only detected Scribble protein on the lateral plasma membrane. Furthermore, Ser 1601-unphosphorylated Scribble was selectively coprecipitated with E-cadherin–catenin complexes in E-cadherin-expressing mouse L fibroblasts. Taken together, these results suggest that the phosphorylation state of Scribble regulates its complex formation with the E-cadherin–catenin system and may control cadherin-mediated cell–cell adhesion. 相似文献
65.
66.
Yu Yokoyama Masaki Tanito Koji Nitta Maki Katai Yasushi Kitaoka Kazuko Omodaka Satoru Tsuda Toshiaki Nakagawa Toru Nakazawa 《PloS one》2014,9(6)
PurposeThe Glaucoma Stereo Analysis Study (GSAS), a cross sectional multicenter collaborative study, used a stereo fundus camera to assess various morphological parameters of the optic nerve head (ONH) in glaucoma patients and investigated the relationships between these parameters and patient characteristics.ResultsPatient characteristics included refractive error of −3.38±3.75 diopters, intraocular pressure (IOP) of 13.6±2.6 mmHg, and visual field mean deviation (MD) of −4.71±3.26 dB. Representative ONH parameters included a horizontal disc width of 1.66±0.28 mm, vertical disc width of 1.86±0.23 mm, disc area of 2.42±0.63 mm2, cup area of 1.45±0.57 mm2, and cup volume of 0.31±0.22 mm3. Correlation analysis revealed significant negative associations between vertical cup-to-disc ratio (0.82±0.08) and MD (r = −0.40, P<0.01) and between disc tilt angle (10.5±12.5 degrees) and refractive error (r = −0.36, P<0.01). Seventy-five percent of the eyes had a positive value for rim decentering (0.30±0.42), indicating that rim thinning manifested more often as an inferior lesion than a superior lesion.ConclusionWe used stereoscopic analysis to establish a database of ONH parameters, which may facilitate future studies of glaucomatous changes in ONH morphology. 相似文献
67.
A novel import route for an N-anchor mitochondrial outer membrane protein aided by the TIM23 complex 下载免费PDF全文
The membrane topology of Om45 in the yeast mitochondrial outer membrane (OM) is under debate. Here, we confirm that Om45 is anchored to the OM from the intermembrane space (IMS) by its N-terminal hydrophobic segment. We show that import of Om45 requires the presequence receptors, Tom20 and Tom22, and the import channel of Tom40. Unlike any of the known OM proteins, Om45 import requires the TIM23 complex in the inner membrane, a translocator for presequence-containing proteins, and the membrane potential (ΔΨ). Therefore, Om45 is anchored to the OM via the IMS by a novel import pathway involving the TIM23 complex. 相似文献
68.
Kanda Y Yamane-Ohnuki N Sakai N Yamano K Nakano R Inoue M Misaka H Iida S Wakitani M Konno Y Yano K Shitara K Hosoi S Satoh M 《Biotechnology and bioengineering》2006,94(4):680-688
Several methods have been described to enhance antibody-dependent cellular cytotoxicity (ADCC) using different host cells that produce antibody with reduced levels of fucose on their carbohydrates. We compared the suitability of these methods for the serum-free fed-batch production of antibody for clinical trials and commercial uses. Recombinant anti-human CD20 chimeric IgG1-producing clones were established from host-cells that have been shown to produce more than 90% fucose-negative antibody. The cell lines were a FUT8 (alpha-1,6-fucosyltransferase) knockout Chinese hamster ovary (CHO) cell line, Ms704, and two Lens culinaris agglutinin (LCA)-resistant cell lines, one derived from a variant CHO line, Lec13 and the other from a rat hybridoma cell line, YB2/0. The amount of fucose-negative antibody produced by Lec13 and YB2/0 significantly decreased with the culture. The increase in fucosylation was due to remaining synthesis of GDP-fucose via de novo pathway for the CHO line and the elevation of FUT8 expression by the YB2/0 cells. In contrast, Ms704 cells stably produced fucose-negative antibody with a consistent carbohydrate structure until the end of the culture. The productivity of the Ms704 cells reached 1.76 g/L with a specific production rate (SPR) of 29 pg/cell/day for 17 days in serum-free fed-batch culture using a 1 L spinner bioreactor. Our results demonstrate that FUT8 knockout has the essential characteristics of host cells for robust manufacture of fucose-negative therapeutic antibodies with enhanced ADCC. 相似文献
69.
Matsukawa K Ogata M Hikage T Minami H Shimotai Y Saitoh Y Yamashita T Ouchi A Tsutsumi R Fujioka T Tsutsumi K 《Bioscience, biotechnology, and biochemistry》2006,70(4):1046-1048
We describe a novel pharmacological activity of the gentian root, an ingredient of Chinese medicines. Root extract from Gentiana triflora triggered cell death of human Daudi cells in culture. In addition, daily administration of the extract to mice inhibited growth of implanted solid tumors. Extract treatment of cultured cells resulted in the appearance of shranken, fragmented, or condensed cell and nuclear morphologies, and in chromosomal DNA degradation. But, the extract-treated cells did not show DNA fragmentation, which exhibits a nucleosome ladder, suggesting that extract-triggered cell death is not mediated through a typical apoptotic pathway. 相似文献
70.
Masayuki Sato Gaku Takahashi Shigehiro Shibata Makoto Onodera Yasushi Suzuki Yoshihiro Inoue Shigeatsu Endo 《PloS one》2015,10(12)
We previously reported that a soluble CD14-subtype (sCD14-ST) immunochromatographic test (ICT) for plasma is more convenient than chemiluminescent enzyme immunoassay (CLEIA), but plasma separation makes bedside measurements difficult. We developed a new sCD14-ST ICT for whole blood and investigated whether quantitative determinations of sCD14-ST by ICT were useful for diagnosing sepsis and severe sepsis/septic shock. We studied 20 patients who fulfilled two or more systemic inflammatory response syndrome (SIRS) criteria and 32 patients who had been diagnosed with sepsis or severe sepsis/septic shock. Whole blood was collected on day 0 (on admission) and day 7, and the sCD14-ST concentration was quantitatively measured by CLEIA and ICT for whole blood. The patients’ Acute Physiology and Chronic Health Evaluation (APACHE) II, Sequential Organ Failure Assessment (SOFA), and Mortality in Emergency Department Sepsis (MEDS) scores were also calculated. The cut-off values obtained by the quantitative measurements made by ICT were 464.5 pg/mL for sepsis and 762.7 pg/mL for severe sepsis/septic shock (P < 0.0001). A Bland–Altman plot showed that no fixed bias or proportional bias was detected between CLEIA and quantitative ICT for whole blood. sCD14-ST concentrations were significantly correlated with APACHE II, SOFA, and MEDS scores (P < 0.0001). These results suggest that the new sCD14-ST ICT for whole blood may be a useful tool for the convenient, rapid bedside diagnosis and treatment of sepsis. 相似文献