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排序方式: 共有2534条查询结果,搜索用时 46 毫秒
1.
人睫状神经营养因子的原核表达,纯化及其生物效应 总被引:2,自引:0,他引:2
人睫状神经营养因子(hCNTF)克隆入pBV220中,在DH5α菌株中表达,重组蛋白以包含体的形式存在,表达量为菌体总蛋白的50%左右。经比较发现用2mol/L脲洗涤包含体可溶解大量可溶性细菌蛋白,且包含体损失较小。在高浓度变性剂条件下进行sepharcylS-200凝胶过滤,解决了纯化中hCNTF易聚合的问题,在低浓度变性剂条件下进行DEAE离子交换,有利于蛋白活性的保持。经两步纯化后得到均一性hCNTF,纯度达95%以上。在自然状态下使hCNTF复性。纯化复性后的hCNTF对无血清培养的鸡胚背根节神经元和脊髓腹角运动神经元有明显的维持存活和促进生长发育的生物效应。 相似文献
2.
Four new hetisine‐type C20‐diterpenoid alkaloids, named as coreanines A–D ( 1 – 4 ), were isolated from the roots of Aconitum coreanum, together with thirteen known alkaloids ( 5 – 17 ). Their structures were elucidated by extensive spectroscopic methods including IR, HR‐ESI‐MS and NMR techniques. All the isolated compounds were screened for the acetylcholinesterase (AChE) inhibitory effects, and none of them showed considerable inhibitory activity. 相似文献
3.
Plant somatic cells have the capability to switch their cell fates from differentiated to undifferentiated status under proper
culture conditions, which is designated as totipotency. As a result, plant cells can easily regenerate new tissues or organs
from a wide variety of explants. However, the mechanism by which plant cells have such remarkable regeneration ability is
still largely unknown. In this study, we used a set of meristem-specific marker genes to analyze the patterns of stem cell
differentiation in the processes of somatic embryogenesis as well as shoot or root organogenesis in vitro. Our studies furnish preliminary and important information on the patterns of the de novo stem cell differentiation during various types of in vitro organogenesis. 相似文献
4.
Xian Zeng Hui Zhao Yubin Li Jiajun Fan Yun Sun Shaofei Wang Ziyu Wang Ping Song Dianwen Ju 《Autophagy》2015,11(2):355-372
The frontline tyrosine kinase inhibitor (TKI) imatinib has revolutionized the treatment of patients with chronic myeloid leukemia (CML). However, drug resistance is the major clinical challenge in the treatment of CML. The Hedgehog (Hh) signaling pathway and autophagy are both related to tumorigenesis, cancer therapy, and drug resistance. This study was conducted to explore whether the Hh pathway could regulate autophagy in CML cells and whether simultaneously regulating the Hh pathway and autophagy could induce cell death of drug-sensitive or -resistant BCR-ABL+ CML cells. Our results indicated that pharmacological or genetic inhibition of Hh pathway could markedly induce autophagy in BCR-ABL+ CML cells. Autophagic inhibitors or ATG5 and ATG7 silencing could significantly enhance CML cell death induced by Hh pathway suppression. Based on the above findings, our study demonstrated that simultaneously inhibiting the Hh pathway and autophagy could markedly reduce cell viability and induce apoptosis of imatinib-sensitive or -resistant BCR-ABL+ cells. Moreover, this combination had little cytotoxicity in human peripheral blood mononuclear cells (PBMCs). Furthermore, this combined strategy was related to PARP cleavage, CASP3 and CASP9 cleavage, and inhibition of the BCR-ABL oncoprotein. In conclusion, this study indicated that simultaneously inhibiting the Hh pathway and autophagy could potently kill imatinib-sensitive or -resistant BCR-ABL+ cells, providing a novel concept that simultaneously inhibiting the Hh pathway and autophagy might be a potent new strategy to overcome CML drug resistance. 相似文献
5.
The 14-3-3 proteins regulate diverse biological processes that are implicated in cancer development, and seven 14-3-3 isoforms were identified with isoform-specific roles in different human tumors. In our previous work, we dissected the interactome of 14-3-3ε formed during the DNA damage response in a hepatocellular carcinoma (HCC) cell using an AACT/SILAC-based quantitative proteomic approach. In this study, we used a similar proteomic approach to profile/identify the 14-3-3ε interactome formed in native HCC cells. Functional categorization and data-dependent network analysis of the native HCC-specific 14-3-3ε interactome revealed that 14-3-3ε is involved in the regulation of multiple biological processes (BPs)/pathways, including cell cycle control, apoptosis, signal transduction, transport, cell adhesion, carbohydrate metabolism, and nucleic acid metabolism. Biological validation further supports that 14-3-3ε, via association with multiple BP/pathway-specific proteins, coordinates the regulation of proliferation, survival, and metastasis of HCC. The findings in this study, together with those of our previous study, provide an extensive profile of the 14-3-3ε interaction network in HCC cells, which should be valuable for understanding the pathology of HCC and HCC therapy. 相似文献
6.
7.
Shu Xian Yan Zhang Li Wang Fang Yao Jinli Ding Yanqing Wang Xiao Yang Fangfang Dai Tailang Yin Yanxiang Cheng 《Journal of cellular and molecular medicine》2021,25(8):3885-3897
The INO80 complex, a SWI/SNF family chromatin remodeler, has regulatory effects on ESC self-renewal, somatic cell reprogramming and blastocyst development. However, the role of INO80 in regulating trophoblast cells and recurrent miscarriage (RM) remains elusive. To investigate the in vivo effects of Ino80 in embryo development, we disrupted Ino80 in C57 mice, which resulted in embryonic lethality. Silencing of Ino80 led to decreased survival capacity, migration and invasion of trophoblasts. Furthermore, RNA high-throughput sequencing (RNA-seq) revealed that Ino80 silencing closely resembled the gene expression changes in RM tissues. To investigate the mechanisms for these results, RNA-seq combined with high-throughput sequencing (ChIP-seq) was used in trophoblast cells, and it showed that Ino80 physically occupies promoter regions to affect the expression of invasion-associated genes. Last, Western blotting analyses and immunofluorescence staining revealed that the content of INO80 was reduced in RM patients compared to in healthy controls. This study indicates that INO80 has a specific regulatory effect on the viability, migration and invasion of trophoblast cells. Combined with its regulation of the expression of invasion-associated genes, it has been proposed that epigenetic regulation plays an important role in the occurrence of RM, potentially informing RM therapeutic strategies. 相似文献
8.
9.
Xia Wei Chan Feng Xiao‐Hui Li Xing‐Xin Mao Hai‐Bin Luo Dong‐Mei Zhang Li Rong Zhen‐Yu Xie Xin Yu Jie Li Wen‐Cai Ye Xiao‐Jun Huang Cui‐Xian Zhang 《化学与生物多样性》2019,16(6)
One new racemic mixture, penicilliode A ( 1 ) and four pairs of enantiomeric polyketides, penicilliode B and C ( 2 and 3 ) and coniochaetone B and C ( 4 and 5 ), were obtained from the starfish‐derived symbiotic fungus Penicillium sp. GGF16‐1‐2. Interestingly, the strain GGF16‐1‐2 can produce enantiomers. The absolute configuration of 1 was determined by X‐ray diffraction (XRD) analysis, and the absolute configurations of 2 – 4 were determined by the optical rotation (OR) values and electronic circular dichroism (ECD) calculations. Compounds 1 – 5 were firstly isolated from the marine‐derived fungus Penicillium as racemates, and 2 – 5 were separated by HPLC with a chiral stationary phase. All the compounds were evaluated for their antibacterial, cytotoxic and inhibitory activities against PDE4D2. 相似文献
10.
Three new 4,5‐seco‐20(10→5)‐abeo‐abietane diterpenoids, 16‐hydroxysalvilenone ( 1 ), 15‐hydroxysalprionin ( 2 ), and 11β,15‐dihydroxysalprionin‐12‐one ( 3 ), and nine known abietane diterpenoids, 4 – 12 , along with one known sempervirane diterpenoid, hispidanol A ( 13 ), were isolated from the aerial parts of Isodon lophanthoides var. graciliflorus. The structures of compounds 1 – 3 were determined on the basis of spectroscopic methods including extensive analysis of NMR and mass spectroscopic data. All diterpenoids were tested for their TNF‐α inhibitory effects on LPS‐induced RAW264.7 cells. Compound 9 (16‐acetoxyhorminone) was the most potent with an IC50 value of 3.97±0.70 μm . 相似文献