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911.
Faqian Xiong Junxian Liu Jing Jiang Ruichun Zhong Liangqiong He Zhuqiang Han Zhong Li Xiumei Tang Ronghua Tang 《Biochemical genetics》2013,51(11-12):889-900
To detect DNA polymorphisms in the peanut, we screened 26 polymorphic primers using intron–exon splice junction (ISJ), universal rice primer (URP), and directed amplification of minisatellite region DNA (DAMD) techniques. Amplification of genomic DNA of 16 peanut accessions yielded 121 ISJ, 50 URP, and 25 DAMD fragments, of which 34, 25 and 16 were polymorphic, respectively. The range of polymorphism was 10.0–62.5%, averaging 27.7%, for ISJ; 20–80%, averaging 49.5%, for URP; and 28.6–50.0%, averaging 36.3%, for DAMD. In comparisons of multiplex ratio, average polymorphism information content, and marker index, the URP markers were relatively more efficient than ISJ and DAMD markers. Clustering results remained more or less the same with ISJ and URP markers. To the best of our knowledge, this is the first report on the study of the genetic diversity of the peanut using ISJ, URP, and DAMD markers. 相似文献
912.
Dhivya Subramanian Junqi Huang Mayalagu Sevugan Robert C. Robinson Mohan K. Balasubramanian Xie Tang 《Genetics》2013,194(2):435-446
Actin is a key cytoskeletal protein with multiple roles in cellular processes such as polarized growth, cytokinesis, endocytosis, and cell migration. Actin is present in all eukaryotes as highly dynamic filamentous structures, such as linear cables and branched filaments. Detailed investigation of the molecular role of actin in various processes has been hampered due to the multifunctionality of the protein and the lack of alleles defective in specific processes. The actin cytoskeleton of the fission yeast, Schizosaccharomyces pombe, has been extensively characterized and contains structures analogous to those in other cell types. In this study, primarily with the view to uncover actin function in cytokinesis, we generated a large bank of fission yeast actin mutants that affect the organization of distinct actin structures and/or discrete physiological functions of actin. Our screen identified 17 mutants with specific defects in cytokinesis. Some of these cytokinesis mutants helped in dissecting the function of specific actin structures during ring assembly. Further genetic analysis of some of these actin mutants revealed multiple genetic interactions with mutants previously known to affect the actomyosin ring assembly. We also characterize a mutant allele of actin that is suppressed upon overexpression of Cdc8p-tropomyosin, underscoring the utility of this mutant bank. Another 22 mutant alleles, defective in polarized growth and/or other functions of actin obtained from this screen, are also described in this article. This mutant bank should be a valuable resource to study the physiological and biochemical functions of actin. 相似文献
913.
914.
Jing Chen Cheng-Shi Jiang Wen-Quan Ma Li-Xin Gao Jing-Xu Gong Jing-Ya Li Jia Li Yue-Wei Guo 《Bioorganic & medicinal chemistry letters》2013,23(18):5061-5065
Bruguiesulfurol (1), a cyclic 4-hydroxy-dithiosulfonate isolated from mangrove plant Bruguiera gymnorrhiza, was concisely synthesized for the first time in four steps, and a series of its synthetic derivatives were evaluated for in vitro inhibitory effects on PTP1B and related PTPs. Some derivatives were found to have improved pharmacological profile compared with hit 1. Among them, 5a showed the potent selectivity towards PTP1B over other PTPs, including TCPTP, and 7j exhibited the strongest PTP1B inhibitory activity with an IC50 value of 4.54 μM. 相似文献
915.
Yao Xu Philip D. Weyman Miki Umetani Jing Xiong Ximing Qin Qing Xu Hideo Iwasaki Carl Hirschie Johnson 《Current biology : CB》2013,23(23):2365-2374
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916.
Xianwen Cao Jing Jiang Shoude Zhang Lili Zhu Juan Zou Yanyan Diao Weilie Xiao Lei Shan Handong Sun Weidong Zhang Jin Huang Honglin Li 《Bioorganic & medicinal chemistry letters》2013,23(11):3329-3333
Eleven compounds were identified as estrogen receptor modulators from an in-house natural product database (NPD) by structure-based virtual screening for ERα and ERβ. Among them, 3 compounds were confirmed as ER agonists and 8 compounds were confirmed as ER antagonists by yeast two-hybrid (Y2H) assay, with EC50 values ranging from several micromolar to 100 micromolar. In this study, a novel series of cycloartane triterpenoids isolated from Schisandra glaucescens Diels was found to have ER antagonistic effect, the most potent antagonist of which exhibited activity with EC50 value of 2.55 and 4.68 μM for ERα and ERβ, respectively. Moreover, the types of modulation and subtype selectivity were also investigated through molecular docking simulation. 相似文献
917.
Weiwei Zhou Fang Yan Jinzhong Fu Shifang Wu Robert W. Murphy Jing Che Yaping Zhang 《Molecular ecology》2013,22(1):130-142
Frequently, Pleistocene climatic cycling has been found to be the diver of genetic structuring in populations, even in areas that did not have continental ice sheets, such as on the Qinghai‐Tibetan Plateau (QTP). Typically, species distributed on the plateau have been hypothesized to re‐treat to south‐eastern refugia, especially during the Last Glacial Maximum (LGM). We evaluated sequence variation in the mitochondrial DNA gene Cytb and the nuclear DNA gene RAG‐1 in Rana kukunoris, a species endemic to the QTP. Two major lineages, N and S, were identified, and lineage N was further subdivided into N1 and N2. The geographical distribution and genealogical divergences supported the hypothesis of multiple refugia. However, major lineages and sublineages diverged prior to the LGM. Demographical expansion was detected only in lineage S and sublineage N2. Sublineage N1 might have survived several glacial cycles in situ and did not expand after the LGM because of the absence of suitable habitat; it survived in river islands. Genetic analysis and environment modelling suggested that the north‐eastern edge of QTP contained a major refugium for R. kukunoris. From here, lineage S dispersed southwards after the LGM. Two microrefugia in northern Qilian Mountains greatly contributed to current level of intraspecific genetic diversity. These results were found to have important implications for the habitat conservation in Northwest China. 相似文献
918.
919.
Xia Wang Yan Li Winnie Deuther-Conrad Fang Xie Xin Chen Meng-Chao Cui Xiao-Jun Zhang Jin-Ming Zhang Jörg Steinbach Peter Brust Bo-Li Liu Hong-Mei Jia 《Bioorganic & medicinal chemistry》2013,21(1):215-222
We report the synthesis and evaluation of a series of fluoro-oligo-ethoxylated 4-benzylpiperazine derivatives as potential σ1 receptor ligands. In vitro competition binding assays showed that 1-(1,3-benzodioxol-5-ylmethyl)-4-(4-(2-fluoroethoxy)benzyl)piperazine (6) exhibits low nanomolar affinity for σ1 receptors (Ki = 1.85 ± 1.59 nM) and high subtype selectivity (σ2 receptor: Ki = 291 ± 111 nM; Kiσ2/Kiσ1 = 157). [18F]6 was prepared in 30–50% isolated radiochemical yield, with radiochemical purity of >99% by HPLC analysis after purification, via nucleophilic 18F? substitution of the corresponding tosylate precursor. The log DpH 7.4 value of [18F]6 was found to be 2.57 ± 0.10, which is within the range expected to give high brain uptake. Biodistribution studies in mice demonstrated relatively high concentration of radiotracers in organs known to contain σ1 receptors, including the brain, lungs, kidneys, heart, and spleen. Administration of haloperidol 5 min prior to injection of [18F]6 significantly reduced the concentration of radiotracers in the above-mentioned organs. The accumulation of radiotracers in the bone was quite low suggesting that [18F]6 is relatively stable to in vivo defluorination. The ex vivo autoradiography in rat brain showed high accumulation of radiotracers in the brain areas known to possess high expression of σ1 receptors. These findings suggest that [18F]6 is a suitable radiotracer for imaging σ1 receptors with PET in vivo. 相似文献
920.
Shaoyi Sun Richard Dean Qi Jia Alla Zenova Jing Zhong Celene Grayson Clark Xie Andrea Lindgren Pritpaul Samra Luis Sojo Margaret van Heek Linus Lin David Percival Jian-min Fu Michael D. Winther Zaihui Zhang 《Bioorganic & medicinal chemistry》2013,21(24):7724-7734
Endothelial lipase (EL) activity has been implicated in HDL metabolism and in atherosclerotic plaque development; inhibitors are proposed to be efficacious in the treatment of dyslipidemia related cardiovascular disease. We describe here the discovery of a novel class of anthranilic acids EL inhibitors. XEN445 (compound 13) was identified as a potent and selective EL inhibitor, that showed good ADME and PK properties, and demonstrated in vivo efficacy in raising plasma HDLc concentrations in mice. 相似文献