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71.
Jianxiong Li Bin Li Yujie Bu Hailin Zhang Jia Guo Jianping Hu Yanfang Zhang 《Molecules and cells》2022,45(4):216
SERTA domain-containing protein 1 (Sertad1) is upregulated in the models of DNA damage and Alzheimer’s disease, contributing to neuronal death. However, the role and mechanism of Sertad1 in ischemic/hypoxic neurological injury remain unclear. In the present study, our results showed that the expression of Sertad1 was upregulated in a mouse middle cerebral artery occlusion and reperfusion model and in HT22 cells after oxygen-glucose deprivation/reoxygenation (OGD/R). Sertad1 knockdown significantly ameliorated ischemia-induced brain infarct volume, neurological deficits and neuronal apoptosis. In addition, it significantly ameliorated the OGD/R-induced inhibition of cell viability and apoptotic cell death in HT22 cells. Sertad1 knockdown significantly inhibited the ischemic/hypoxic-induced expression of p-Rb, B-Myb, and Bim in vivo and in vitro. However, Sertad1 overexpression significantly exacerbated the OGD/R-induced inhibition of cell viability and apoptotic cell death and p-Rb, B-Myb, and Bim expression in HT22 cells. In further studies, we demonstrated that Sertad1 directly binds to CDK4 and the CDK4 inhibitor restores the effects of Sertad1 overexpression on OGD/R-induced apoptotic cell death and p-Rb, B-Myb, and Bim expression in HT22 cells. These results suggested that Sertad1 contributed to ischemic/hypoxic neurological injury by activating the CDK4/p-Rb pathway. ON123300相似文献
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Yujie Huang Ruijuan Liu Xuechao Han Xiaoyan Hou Yonghao Tian Weifang Zhang 《International journal of biological sciences》2022,18(1):112
Persistent infection with high-risk human papillomavirus (HPV) is the main risk factor for cervical cancer. Our mass spectrometry data showed that the Ras-associated binding protein Rab31 was upregulated by HPV; however, little is known regarding the role of Rab31 in the metastasis of cervical cancer cells. In this study, we showed that Rab31 was highly expressed in cervical cancer tissues and cells, and both HPV E6 and E7 promoted the expression of Rab31. Rab31 knockdown inhibited while Rab31 overexpression promoted the migration and invasion capabilities of cervical cancer cells. Additionally, Rab31 knockdown inhibited the epithelial-mesenchymal transition (EMT) and cytoskeletal rearrangement in cervical cancer cells. Furthermore, Rab31 interacted with mitogen-activated protein kinase 6 (MAPK6), and Rab31 knockdown inhibited the expression of MAPK6, which was mainly localized in the cytoplasm. More importantly, Rab31 knockdown promoted and Rab31 overexpression inhibited MAPK6 degradation. Accordingly, MAPK6 overexpression restored the decreased migration potential caused by Rab31 knockdown. Finally, a xenograft mouse model showed that Rab31 knockdown in cervical cancer cells led to reduced tumor growth and impaired lung and liver metastasis in vivo. In conclusion, Rab31 plays a crucial role in cervical cancer metastasis by inhibiting MAPK6 degradation. Thus, Rab31 may serve as a novel therapeutic target to manage cervical cancer. 相似文献
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Kim TS Hague AB Lee TI Lian B Tegley CM Wang X Burgess TL Qian YX Ross S Tagari P Lin CH Mayeda C Dao J Jordan S Mohr C Cheetham J Viswanadhan V Tasker AS 《Bioorganic & medicinal chemistry letters》2004,14(1):87-90
A series of (4-piperidinylphenyl)aminoethyl amides based on dipeptide anilines were synthesized and tested against cathepsin K, cathepsin L and cathepsin B. These new non-covalent inhibitors exhibited single-digit nM inhibition of the cysteine proteases. Compounds 3 and 7 demonstrated potency in both mouse and human osteoclast resorption assays. 相似文献
77.
Huang J Bai YX Han SW Ng SS Jing DD Wong BC Huang CF Kung HF Lin MC 《Biochemical and biophysical research communications》2003,301(3):627-632
We have constructed a 27-kDa hTERT C-terminal polypeptide (hTERTC27) devoid of domains required for telomerase activity and demonstrated that it is capable of nuclear translocation/telomere-end targeting. Here we showed that expression of a low level of hTERTC27 renders hTERT positive HeLa cells sensitive to H(2)O(2)-induced oxidative stress and subsequent cell senescence. The senescence-associated gene, the cyclin/cdk inhibitor p21(Waf1), was up-regulated. This occurs without changing the expression of endogenous hTERT, causing significant telomere shortening or inhibiting telomerase activity. Results from this study suggest for the first time that in addition to telomerase activity, the C-terminus of hTERT also plays a role in hTERT-mediated cellular resistance to oxidative stress. 相似文献
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Streptococcus mutans plays a primary role in the formation of dental caries. Previously, in our laboratory, an S. mutans genomic library was prepared, and the wapA gene was cloned into the shuttle vector, pSA4/4B2. To generate overexpression of wapA and to facilitate efficient purification of the WapA protein for use as an immunogen, an expression vector with the strong tac promoter was used. In order to answer questions regarding the optimization of solubility and expression based on gene size or the hydrophobicity of the protein product, 12 truncated constructs of the wapA gene were prepared using PCR. The truncated products were subcloned into the pGEX-6P-1 glutathione S-transferase (GST) fusion vector and expressed in E. coli BL21. The fusion proteins were analyzed by SDS-PAGE and confirmed by analysis with anti-GST and anti-WapA antibodies. Our study suggests that abrogation of the wapA promoter is necessary for expression of this gene in this expression system. Deletion of the signal peptide and the hydrophobic C terminus of WapA increased expression compared with the full-length construct, and truncation at the protease cleavage site of the C-terminal region greatly increased the stability of the protein without a loss in reactivity with the anti-WapA antibody. Western immunoblot analysis with anti-WapA antiserum clearly showed that the majority of the epitopes of the GST-WapA fusions are located in the N-terminal region of WapA. The immunogenicity of the various WapA fusion products is being examined in mice and rats to further map the immunologically dominant regions of the protein. This method effectively increased the expression of WapA and should contribute to the further understanding of gene expression of E. coli, as well as aid in the characterization of this protein for future immunologic evaluation. 相似文献
79.
柑桔原生质体辐射诱变筛选抗寒再生植株 总被引:3,自引:0,他引:3
用1161C/kg软X射线辐射“Page”桔柚(CitrusreticulataBlanco×C.grandisOsb.cv.Page)胚性愈伤组织分离的原生质体,经-11℃低温选择后,将存活的原生质体培养再生植株。研究表明,“Page”桔柚胚性愈伤组织原生质体在4128C/kg辐射剂量处理后几乎不能恢复分裂;2064C/kg辐射时分裂频率低,即使分裂也难以发育为胚状体;而1161C/kg辐射后,经-11℃低温处理仍有102%~169%的分裂频率,且部分细胞团能发育为胚状体。辐射的原生质体培养成胚状体后,经低温筛选,在改良的生芽培养基和生根培养基中萌发成为植株。再生植株中检测出2株的叶片原生质体的低温半致死温度(LT50)分别比对照低1.96℃和168℃。 相似文献
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