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101.
Jing‐Yuan Chuang Wei‐Hung Yang Hsien‐Te Chen Chun‐Yin Huang Tzu‐Wei Tan Yuh‐Tzy Lin Chin‐Jung Hsu Yi‐Chin Fong Chih‐Hsin Tang 《Journal of cellular physiology》2009,220(2):418-426
CCL5 (previously called RANTES) is in the CC‐chemokine family and plays a crucial role in the migration and metastasis of human cancer cells. On the other hand, the effect of CCL5 is mediated via CCR receptor. RT‐PCR and flow cytometry studies demonstrated CCR5 but not CCR1 and CCR3 mRNA in oral cancer cell lines, especially higher in those with high invasiveness (SCC4) as compared with lower levels in HSC3 cells and SCC9 cells. Stimulation of oral cancer cells with CCL5 directly increased the migration and metalloproteinase‐9 (MMP‐9) production. MMP‐9 small interfering RNA inhibited the CCL5‐induced MMP‐9 expression and thereby significantly inhibited the CCL5‐induced cell migration. Activations of phospholipase C (PLC), protein kinase Cδ (PKCδ), and NF‐κB pathways after CCL5 treatment was demonstrated, and CCL5‐induced expression of MMP‐9 and migration activity was inhibited by the specific inhibitor of PLC, PKCδ, and NF‐κB cascades. In addition, migration‐prone sublines demonstrate that cells with increasing migration ability had more expression of MMP‐9, CCL5, and CCR5. Taken together, these results indicate that CCL5/CCR5 axis enhanced migration of oral cancer cells through the increase of MMP‐9 production. J. Cell. Physiol. 220: 418–426, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
102.
103.
从中国发病鸡中分离的鸡减蛋综合征病毒(EggDropSyndromVirus,EDSV)弱毒株(AA-2),其基因组全长约为33kb。用限制性内切酶HindⅢ水解EDSV全基因组,构建了以pBluescriptⅡ(KS+)为载体的右末端片段的克隆(约4.2kb),对其进行了序列测定和结构分析。该片段全长4183个碱基对(bp),位于基因组右末端87.3m.u.-100m.u.。结果显示,该片段与哺乳动物腺病毒右末端E4区结构不同,与禽Ⅰ型腺病毒代表株CELO右末端片段亦无同源性。本文为深入了解EDSV基因组结构特点,EDSV与其他腺病毒基因结构与功能的进化关系和EDSV载体的构建奠定了分子生物学基础 相似文献
104.
本文对2022年《生物工程学报》发表的与合成生物制造相关的综述和研究论文进行了评述,重点讨论了DNA测序、DNA合成、DNA编辑、基因表达调控和数学细胞模型等底层技术,酶的设计、改造和应用技术,化学品生物催化、氨基酸及其衍生物、有机酸、天然化合物、抗生素与活性肽、功能多糖、功能蛋白质等重要产品的生物制造技术,一碳化合物和生物质原料利用技术以及合成微生物组技术,以帮助读者从一个侧面了解合成生物制造相关技术和产业的发展情况。 相似文献
105.
Zhen-Yu Zhang Yin Mai Hao Yang Pei-Yue Dong Xue-Li Zheng Gong-She Yang 《Molecular and cellular biochemistry》2014,395(1-2):53-64
The process of preadipocytes differentiation plays a vital role in adipose tissue expansion and many factors are involved in this event. Cathepsin B (CTSB), secreted from lysosome, has been reported in regulating a variety of physiological processes. In this study, we demonstrated CTSB promotes lipid accumulation and adipogenic genes expression in porcine primary preadipocytes by degrading fibronectin (Fn), a key component of extracellular matrix. Lithium chloride (LiCl) is an activator of Wnt/β-catenin signaling through stabilizing β-catenin. We found that CTSB can relieve the anti-adipogenic effects of LiCl, indicating that CTSB could impact Wnt/β-catenin signaling pathway. Interestingly, Fn is an important target gene of Wnt/β-catenin. So we considered that CTSB promote preadipocytes differentiation by suppressing these two pathways. 相似文献
106.
降解三硝基甲苯的酵母和类酵母菌的研究 总被引:9,自引:0,他引:9
从受三硝基甲苯(TNT)严重污染的土壤和废水中分离筛选到17株可降解TNT的酵母菌和白地霉。其中6株为克鲁斯假丝酵母(Candidakrusei),4株为橡树假丝酵母(C.quercitrusa),一株为无名假丝酵母(C.famata),一株为伯杰汉逊酵母(Hansenulabeijerinckii),一株为亚膜汉逊酵母(H.subpelliculosa),4株为白地霉(Geotrichumcandidum)。对其中6株菌进行了降解TNT的条件实验,发现降解TNT的适宜pH为7,温度为37~40℃。在含75~80mg/LTNT的培养基中,40h内能降解TNT56~74mg/L,去除率达71%~93%。在培养基中加入0.01%~0.05%的葡萄糖作碳源,或加入0.01%~0.1%的酵母膏对6株菌降解TNT的能力略有促进作用。加入铵盐作为氮源则明显抑制这些菌对TNT的降解。 相似文献
107.
薄层色谱-分光光度法测定樟芝菌粉中的总三萜含量 总被引:1,自引:0,他引:1
采用薄层色谱(TLC)-分光光度法测定樟芝菌粉中的总三萜含量.结果表明,适宜的展开剂组成为氯仿:甲醇=9:1.该方法排除了樟芝菌粉中含有的脂肪等物质对测定总三萜含量的干扰,其准确度明显高于直接分光光度法和重量法,同时该方法具有较好的精密度,准确度及稳定性. 相似文献
108.
Ying Yin Bailiang Xu Zhiyong Li Baohua Zhang 《World journal of microbiology & biotechnology》2013,29(3):441-446
(+)-Terrein is a fungal metabolite with multiple biological activities, especially with great value in medicine. However, the mass production of single configuration terrein is still a big challenge. In this study, the effects of acetic acid, sodium acetate, citric acid and sodium citrate on the (+)-terrein production by Aspergillus terreus strain PF26 derived from marine sponge Phakellia fusca were investigated. Sodium citrate was selected for fed-batch cultivation because it showed the best effect on (+)-terrein production among the four regulators tested. As a result, 5.38 g/L (+)-terrein production was achieved by feeding 10 mM sodium citrate on the 3rd day in shake flask, which was 33.8 % higher than the control and represented the highest yield of (+)-terrein. In a 7.5-L stirred bioreactor, 2.58 g/L of (+)-terrein production was achieved by the feeding of 10 mM sodium citrate on the 8th day. The results from this study lay a basis for the high-yield production of (+)-terrein by fermentation. 相似文献
109.
The population genetic structure and demographic history of the ground beetle Pheropsophus jessoensis (Coleoptera: Carabidae) from the Tsinling-Dabashan Mountains, central China were estimated using the mtDNACol-tRNALeu-mtDNAColl region as a molecular marker. 184 individuals from 25 local populations, were collected. The haplotype diversity (H(d)) of total and each individual sampled population was high, and was accompanied by lower nucleotide diversity (P(i)). AMOVA analysis suggested that most of the variation was within populations (92.17%), while differentiation of among populations only contributed 7.83% to the total. Mantel test results showed significant correlation between the pairwise calculated genetic distance and pairwise calculated geographical distance of the populations (R(xy) = 0.360529, P = 0.00001 < 0.01), indicating the presence of isolationby-distance. No phylogeographic structure was found within the Tsinling-Dabashan Mountains region. Statistical phylogeographic analysis indicated that the contemporary populations are derived from multiple ancestral-refugial source populations. Gene flow calculated through the N(m) was high between many pairs of populations, which was probably due to ancient vicariance and subsequent rapid expansion of populations. The results of neutral test, mismatch distribution analyses, and Bayesian Skyline Plot (BSP) analysis together indicated a sudden demographic expansion. The estimated expansion time of individual haplogroup and the whole sampled population were 0.012-0.278 Myr, and a sudden expansion was identified between 0.05 Myr to 0.01 Myr by BSP. The postglacial population expansion might lead to the lack of phylogeographic structure. 相似文献
110.
丝状真菌瑞氏木霉外源基因表达系统的构建 总被引:5,自引:0,他引:5
采用PCR技术体外扩增获得了瑞氏木霉外切葡聚糖纤维二糖水解酶Ⅰ (CBHⅠ )启动子和终止子序列 .并以大肠杆菌质粒pUC1 9为骨架 ,在该启动子和终止子序列间加入多克隆位点 ,构建了瑞氏木霉强表达整合型载体pTRIL .以质粒pAN7 1为模板 ,体外扩增了带有潮霉素磷酸转移酶(hph)基因的DNA片段 ,将hph插入pTRIL的cbh1启动子和终止子序列之间 ,构建了Pcbh1 hph Tcbh1表达盒 .用此表达盒转化瑞氏木霉C30原生质体 ,在潮霉素平板上得到 1 5株抗性转化子 .对其中的H1转化子进行了PCR和Southern印迹分析 ,证实hph基因确实整合到转化子染色体DNA上 ,并在Pcbh1 启动子控制下进行高效表达 .转化子H1对潮霉素抗性达 1 5 0mg L ,比出发菌株提高 2倍 .瑞氏木霉强表达整合型载体pTRIL的构建成功为开展瑞氏木霉分子生物学研究以及进一步的工程菌株构建工作奠定了基础 相似文献