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991.
Guang-Cai Li Xu-Ling Qin Huai-Hua Song Ying-Ni Li Yu-Yan Qiu Shi-Chang Cui Yong-Sheng Wang Hui Wang Jun-Ling Gong 《Journal of cellular physiology》2019,234(12):22331-22342
Ovarian cancer characterizes as the fourth leading consequence of death associated with cancer for women. Accumulating evidence underscores the vital roles of microRNAs (miRNAs) in preventing ovarian cancer development. Besides, induction of the phosphatidylinositol-3 kinase/serine/threonine kinase (PI3K/Akt) pathway associated with the ovarian cancer cell migration and invasion. The study aims to examine the effects of miR-15b on the proliferation, apoptosis, and senescence of human ovarian cancer cells by binding to lysophosphatidic acid receptor 3 (LPAR3) with the involvement of the PI3K/Akt pathway. The positive expression of LPAR3 protein was detected by immunohistochemistry. Then the interaction between miR-15b and LPAR3 was examined. The possible role of miR-15b in ovarian cancer was explored using gain- and loss-of-function experiments. Subsequently, the functions of miR-15b on PI3K/Akt pathway, proliferation, migration, invasion, senescence and apoptosis of ovarian cancer cells were assessed. Furthermore, in vivo tumorigenicity assay in nude mice was performed. LPAR3 was overexpressed, whereas miR-15b was poorly expressed in ovarian cancer tissues. LPAR3 is a direct target of miR-15b. Restored miR-15b promoted Bax expression, apoptosis, and senescence, inhibited expression of LPAR3 and Bcl-2, the extent of PI3K and Akt phosphorylation, as well as ovarian cancer cell proliferation, migration, and invasion. Further, tumor growth was observed to be prevented by miR-15b overexpression. Collectively, our study demonstrates that miR-15b represses the proliferation and drives the senescence and apoptosis of ovarian cancer cells through the suppression of LPAR3 and the PI3K/Akt pathway, highlighting an antitumorigenic role of miR-15b. 相似文献
992.
993.
水杉愈伤组织诱导及植株再生 总被引:2,自引:0,他引:2
通过愈伤组织诱导器官发生途径, 建立了水杉(Metasequoia glyptostroboides)的植株再生体系, 探讨了不同外植体
(种胚、幼叶切块、茎段、根段)和植物生长调节剂对不定芽直接再生和愈伤组织诱导器官发生的影响。结果表明: 以种胚、无菌苗叶片、茎段和根作为外植体, 在MS补加2,4-D、NAA和6-BA不同组合的培养基上都能诱导得到愈伤组织, 其中种胚诱导愈伤组织效果最好, 诱导率可达100%, 茎诱导效果次之, 诱导率为97.1%。诱导愈伤组织效果较好的培养基有:MS+1.0 mg·L–1 2,4-D + 0.5 mg·L–1 6-BA、MS + 0.1 mg·L–1 6-BA + 1.0 mg·L–1 NAA、MS + 0.5 mg·L–1 6-BA+1.0 mg·L–1 NAA、MS+1.0 mg·L–1 6-BA+1.0 mg·L–1 NAA、MS+0.5 mg·L–1 6-BA+2.0 mg·L–1 NAA、MS+1.0 mg·L–1 6-BA + 2.0 mg·L–1 NAA和MS + 0.5 mg·L–1 2,4-D + 0.5 mg·L–1 NAA。以愈伤组织在MS培养基上植株再生效果最好, 再生率为62.5%。 相似文献
994.
We developed a self-formed adaptor PCR (termed SEFA PCR) which can be used for chromosome walking. Most of the amplified flanking sequences were longer than 2.0 kb, and some were as long as 6.0 kb. SEFA PCR is simple and efficient and should have broad applications in the isolation of unknown sequences in complex genomes. 相似文献
995.
Blockade of the CFTR chloride channel by glibenclamide was studied in Xenopus oocytes using two-electrode voltage-clamp recordings, macropatch recordings, and summations of single-channel currents, in order to test a kinetic model recently developed by us from single-channel experiments. Both the forward and reverse macroscopic reactions, at negative and positive membrane potential VM, respectively, were slow in comparison to those reactions for other CFTR pore blockers such as DPC and NPPB, resulting in prominent relaxations on the order of tens of milliseconds. The rate of the reverse reaction was voltage-dependent, and dependent on the Cl– driving force, while that of the forward reaction was not. In inside-out macropatches, block and relief from block occurred in two distinct phases that differed in apparent affinity. The results are consistent with the presence of multiple glibenclamide binding sites in CFTR, with varying affinity and voltage dependence; they support the kinetic model and suggest experimental approaches for identification of those sites by mutagenesis. 相似文献
996.
Abscisic acid and sucrose regulate tomato and strawberry fruit ripening through the abscisic acid‐stress‐ripening transcription factor 下载免费PDF全文
997.
Guanghui Cui 《Cell biology international》2009,33(3):434-441
Mouse embryonic fibroblasts (MEFs) have been used as feeder cells to support the growth of mouse embryonic stem cell (mESC) and primordial germ cells (PGC) in culture for many years. However, MEF preparation is a complex and tedious task. Recently, there are reports indicating that the microenvironment provided by bone marrow stromal cells could support the survival of embryonic-like stem cells in bone marrow. In this report, rat bone marrow derived mesenchymal progenitor cells (MPC) were used as feeder cells to culture mouse Oct4-GFP ES cell and ES cell derived germ cells. FACS results show that similar to MEF, rat MPC could efficiently support growth of the mouse Oct4-GFP ES cell line in culture (MPC 85.5 ± 5.1% vs MEF 84.1 ± 6.2%). ES cells could be subcultured for >15 passages without losing morphological characteristics. The cultured cells expressed stem cell marker alkaline phosphatase, Oct4, Sox2, and SSEA-1. Furthermore, rat MPC cells were able to support survival of germ cells isolated from mouse Oct4-GFP ES cell formed embryoid bodies (EB). After induction by retinoic acid for 7 days, some isolated cells differentiated to spermatogonial stem-like cells, expressing Mvh, Stra-8, Hsp90-α, integrinβ1 and α6. Compared with traditional MEF culture systems, the rat MPC culture system is effective in supporting ES cell growth and is easy to prepare. 相似文献
998.
Differential plant species responses to interactions of sand burial,precipitation enhancement and climatic variation promote co‐existence in Chinese steppe vegetation 下载免费PDF全文
999.
茄子microRNAs与其靶基因的生物信息学预测 总被引:2,自引:0,他引:2
microRNAs(miRNAs)是一类在真核生物中发现的长度为21 nt左右、非编码、内源性的单链小分子RNA,通过与靶基因的互补发挥转录后水平的负调控作用。目前,已在许多物种中报道了miRNAs的存在,然而还未见关于茄子miRNAs的报道。根据miRNAs在植物中的高度保守性及其前体的二级结构特征,文章通过同源预测的方法,将已知植物的miRNAs与茄子EST数据库比对,经过一系列的筛选,最终预测到12个家族的16条茄子miRNAs,其中包括3个miRNA家族的正义/反义miRNAs,而miR390和miR399家族的正义/反义miRNAs属于第一次发现。文章还通过在线软件psRNATarget预测到15条茄子miRNAs的71个靶基因,这些靶基因主要编码与茄子生长发育、新陈代谢以及胁迫响应等过程相关的蛋白。 相似文献
1000.
Gang Fan Mario Kaßmann Yingqiu Cui Claudia Matthaeus Sverine Kunz Cheng Zhong Shuai Zhu Yu Xie Dmitry Tsvetkov Oliver Daumke Yu Huang Maik Gollasch 《Aging cell》2020,19(4)
Caveolae position CaV3.2 (T‐type Ca2+ channel encoded by the α‐3.2 subunit) sufficiently close to RyR (ryanodine receptors) for extracellular Ca2+ influx to trigger Ca2+ sparks and large‐conductance Ca2+‐activated K+ channel feedback in vascular smooth muscle. We hypothesize that this mechanism of Ca2+ spark generation is affected by age. Using smooth muscle cells (VSMCs) from mouse mesenteric arteries, we found that both Cav3.2 channel inhibition by Ni2+ (50 µM) and caveolae disruption by methyl‐ß‐cyclodextrin or genetic abolition of Eps15 homology domain‐containing protein (EHD2) inhibited Ca2+ sparks in cells from young (4 months) but not old (12 months) mice. In accordance, expression of Cav3.2 channel was higher in mesenteric arteries from young than old mice. Similar effects were observed for caveolae density. Using SMAKO Cav1.2?/? mice, caffeine (RyR activator) and thapsigargin (Ca2+ transport ATPase inhibitor), we found that sufficient SR Ca2+ load is a prerequisite for the CaV3.2‐RyR axis to generate Ca2+ sparks. We identified a fraction of Ca2+ sparks in aged VSMCs, which is sensitive to the TRP channel blocker Gd3+ (100 µM), but insensitive to CaV1.2 and CaV3.2 channel blockade. Our data demonstrate that the VSMC CaV3.2‐RyR axis is down‐regulated by aging. This defective CaV3.2‐RyR coupling is counterbalanced by a Gd3+ sensitive Ca2+ pathway providing compensatory Ca2+ influx for triggering Ca2+ sparks in aged VSMCs. 相似文献