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991.
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
992.
野生大豆种子蛋白含量差异的生理及结构基础的探讨 总被引:1,自引:0,他引:1
利用SDS-聚丙烯酰胺凝胶电泳、电子显微镜、蛋白及酰脲含量测定等技术,对高蛋白含量(50.7% )的50359 和低蛋白含量(40.8% )的50305 两个野生大豆在种子发育过程中贮藏蛋白积累的速率、蛋白组分合成的起始时间、蛋白体发育的进程以及幼茎的酰脲含量进行了比较研究。结果表明:野生大豆50359的高蛋白含量是与其种子发育过程中较高的植株酰脲含量、较早较快的贮藏蛋白合成及积累速率,液泡中高效的蛋白贮藏方式以及蛋白体在子叶细胞中占有较大体积相联系的 相似文献
993.
Zirui Liu Yiquan Li Yilong Zhu Nan Li Wenjie Li Chao Shang Gaojie Song Shanzhi Li Jianan Cong Tingyu Li Zhiru Xiu Jing Lu Chenchen Ge Xia Yang Yaru Li Lili Sun Xiao Li Ningyi Jin 《International journal of biological sciences》2022,18(2):717
Apoptin is a small molecular weight protein encoded by the VP3 gene of chicken anemia virus (CAV). It can induce apoptosis of tumor cells and play anti-tumorigenic functions. In this study, we identified a time-dependent inhibitory role of apoptin on the viability of HCT116 cells. We also demonstrated that apoptin induces pyroptosis through cleaved caspase 3, and with a concomitant cleavage of gasdermin E (GSDME) rather than GSDMD. GSDME knockdown switched the apoptin-induced cell death from pyroptosis to apoptosis in vitro. Furthermore, we demonstrated that the effect of apoptin on GSDME-dependent pyroptosis could be mitigated by caspase-3 and caspase-9 siRNA knockdown. Additionally, apoptin enhanced the intracellular reactive oxygen species (ROS), causing aggregation of the mitochondrial membrane protein Tom20. Moreover, bax and cytochrome c were released to the activating caspase-9, eventually triggering pyroptosis. Therefore, GSDME mediates the apoptin-induced pyroptosis through the mitochondrial apoptotic pathway. Finally, using nude mice xenografted with HCT116 cells, we found that apoptin induces pyroptosis and significantly inhibits tumor growth. Based on this mechanism, apoptin may provide a new strategy for colorectal cancer therapy. 相似文献
994.
Qun Li Zhiyuan Han Navleen Singh Berta Terr Ryann M. Fame Uzayr Arif Thomas D. Page Tasneem Zahran Ahmed Abdeltawab Yuan Huang Ping Cao Jun Wang Hao Lu Hart G. W. Lidov Kameswaran Surendran Lizhao Wu James Q. Virga Ying-Tao Zhao Ulrich Schüller Robert J. Wechsler-Reya Maria K. Lehtinen Sudipto Roy Zhongmin Liu Travis H. Stracker Haotian Zhao 《Cell death and differentiation》2022,29(8):1596
995.
996.
插入序列共同区元件:细菌中新出现的一种基因捕获系统 总被引:1,自引:0,他引:1
摘要:插入序列共同区(Insertion sequence common region,ISCR)元件是一类在结构和功能上与IS91家族相似的特殊插入序列,特点是缺少了末端反向重复序列(Inverted repeats, IRs),在插入位点不产生直接重复序列,并通过滚环式(Rolling circle, RC)进行转座。ISCR元件作为一种新的基因捕获系统,它可以移动邻近的任何DNA序列,为耐药基因在不同种属细菌间水平传播提供了高效的媒介。世界各地多种革兰氏阴性病原菌中已发现有19种ISCR元件,大部分ISCR元件同时携带了多种耐药基因,提示ISCR有可能会造成细菌多重耐药性的快速传播。本文就ISCR结构特征、类型、移动方式、起源及进化的研究进展进行了综述。 相似文献
997.
Chromosome breakage caused by mutagens in male germ cells can be analyzed by micronucleus induction during meiotic division. This can be followed in vitro by culturing seminiferous tubular segments from stages of the epithelial cycle that contain late pachytene and diakinetic primary spermatocytes. We studied the mutagenic potential of a male contraceptive, gossypol, in this test system using adriamycin (10 ng/ml) as a reference mutagen. A small but significant increase in the frequency of micronuclei was induced with concentrations of 10 and 20 micrograms/ml of gossypol, while cytotoxic effects appeared at concentration of 20 micrograms/ml and were evident at 50 micrograms/ml. Analysis of meiotic micronucleus induction in vitro seems to be a sensitive test system of male germ-cell mutagenesis, but further studies on the possible mutagenic effects of gossypol are needed. 相似文献
998.
Yanyi Liu Michael Clark Qifeng Zhang Danmei Yu Dawei Liu Jun Liu Guozhong Cao 《Liver Transplantation》2011,1(2):194-202
Nanostructured V2O5 thin films have been prepared by means of cathodic deposition from an aqueous solution made from V2O5 and H2O2 directly on fluorine‐doped tin oxide coated (FTO) glasses followed by annealing at 500°C in air, and studied as film electrodes for lithium ion batteries. XPS results show that the as‐deposited films contained 15% V4+, however after annealing all the vanadium is oxidized to V5+. The crystallinity, surface morphology, and microstructures of the films have been investigated by means of XRD, SEM, and AFM. The V2O5 thin film electrodes show excellent electrochemical properties as cathodes for lithium ion intercalation: a high initial discharge capacity of 402 mA h g?1 and 240 mA h g?1 is retained after over 200 cycles with a discharging rate of 200 mA g?1 (1.3 C). The specific energy density is calculated as 900 W h kg?1 for the 1st cycle and 723 W h kg?1 for the 180th cycle when the films are tested at 200 mA g?1 (1.3 C). When discharge/charge is carried out at a high current density of 10.5 A g?1 (70 C), the thin film electrodes retain a good discharge capacity of 120 mA h g?1, and the specific power density is over 28 kW kg?1. 相似文献
999.
Novel hybrid SiO2‐coated CdTe quantum dots (QDs) were created using CdTe QDs coated with a hybrid SiO2 shell containing Cd2+ ions and a sulfur source via a sol–gel process in aqueous solution. Aqueous CdTe QDs with tunable emitting color created through a reaction between cadmium chloride and sodium hydrogen telluride was used as cores for the preparation of hybrid SiO2‐coated CdTe QDs. In our experiments we found that the surface state of the cores and preparation conditions that affect the formation of the hybrid SiO2 shell also greatly affect photoluminescence of the hybrid SiO2‐coated CdTe QDs. The generation of CdS‐like clusters in the vicinity of the CdTe QDs, caused the quantum size effect of the QDs to be greatly reduced, which changes photoluminescence properties of the hybrid QDs fundamentally. Namely, the novel hybrid SiO2 shell played an important role in generating a series of specific optical properties. In addition, the novel hybrid SiO2 shell can be created if no CdTe QD is added. In order to gain an insight into the inter structure of the hybrid shell, we characterized the hybrid SiO2‐coated CdTe QDs using X‐ray diffraction analysis and discuss the formation mechanism of such a hybrid structure. This work is significant because the novel hybrid SiO2‐coated CdTe QDs with its excellent properties can be used in many applications, such as biolabeling and optoelectronic devices. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
1000.
It is well-known that there is a large amount of antimicrobial peptides in amphibian skins but few antimicrobial peptides are found in amphibian brains. Twenty-two and four antimicrobial peptides were purified and characterized from the brain homogenate of Bombina maxima and B. microdeladigitora, respectively. One hundred fifty-eight cDNA clones encoding 79 antimicrobial peptides were isolated from brain cDNA libraries of B. maxima and B. microdeladigitora. These antimicrobial peptides belong to two peptide groups (maximin and maximin-H). Twenty of them are identical to previously reported antimicrobial peptides (maximin 1-8, 10, 11, maximin H1, 3-5, 7, 9, 10, 12, 15, 16) from B. maxima skin secretions. Fifty-nine of them are novel antimicrobial peptides. Some of these antimicrobial peptides showed strong antimicrobial activities against tested microorganism strains including Gram-positive and -negative bacteria and fungi. The current diversity in peptide coding cDNA sequences is, to our knowledge, the most extreme yet described for any animal brains. The extreme diversity may give rise to interest to prospect the actual functions of antimicrobial peptides in amphibian brains. 相似文献