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901.
ADAM family consists of a number of transmembrane proteins that contain a disintegrin and metalloprotease domain. ADAMs are involved in a highly diverse set of biological processes, including fertilization, neurogenesis, myogenesis and inflammatory response. The ADAM proteins have both cell adhesion and protease activities.Adam22 is highly expressed in human brain. Theadam22-/- mice presented severe ataxia and died before weaning, but the function of ADAM22 is still unknown. 14-3-3 β interacting with ADAM22 was detected by using yeast two-hybrid assay. The specificity of interaction between ADAM22 and 14-3-3β was proved byin vitro binding assay and immunoprecipitation. The major 14-3-3β binding site was located in the last 28 amino acid residues of ADAM22 cytoplasmic tail. Protein 14-3-3β is abundant and plays an important role in mediating cell diffusion, migration and cell cycle control. The interaction of ADAM22 and 14-3-3β suggests that the ADAM22 may play a crucial role in neural function and development.  相似文献   
902.
用免疫细胞化学技术研究了血管活性肠肽(VIP)阳性神经元在家鸽(Columba livia)视顶盖和峡核中的分布,实验结果表明.在顶盖中VIP阳性神经元主要分布在Ⅱ_1层.并有少数VIP阳性神经元位于Ⅱ_1和Ⅲ层,在峡核大细胞部(Ime)和峡核小细胞部(Ipc),VIP阳性神经元基本呈均匀分布,在Imc和Ipc内分别占细胞总数的80%和50%.  相似文献   
903.
904.
利用生物信息学预测rVvhA的141-335位氨基酸片段有膜成孔模序。基因克隆表达得到95%以上纯度的rMpf,电子透射电镜观察其能够抑制Hela细胞生长且呈剂量依赖性,即0.8,1.6,2.4μg/mL rMpf作用8 h后,细胞和线粒体形态均发生凋亡和坏死改变,细胞内活性氧产生明显,线粒体膜电位下降,mPTP荧光检测膜通道孔活性增强。以上结果表明,rMpf具有诱导Hela细胞损伤的生物学活性,可通过改变膜通透性引起细胞凋亡。  相似文献   
905.
906.
Porcine orthoreoviruses belong to the family Reoviridae and cause mainly mild enteritis in piglets. We present here the complete genome sequence of a novel porcine orthoreovirus strain (GD-1) isolated from a piglet in southern China. Our data will facilitate future investigations of the molecular characteristics and epidemiology of porcine orthoreoviruses.  相似文献   
907.
动物基因敲除研究的现状与展望   总被引:10,自引:4,他引:10  
李湘萍  徐慰倬  李宁 《遗传》2003,25(1):81-88
基因打靶技术是建立在胚胎干细胞和同源重组技术之上,可对基因组进行定位修饰的实验方法,尤其可以在转基因动物的遗传性状修饰中起到巨大的作用。本文简述了转基因、体细胞克隆和基因打靶的研究历史,以及这些技术对转基因动物制备的影响和展望。  相似文献   
908.
重组大肠杆菌热稳定性过氧化氢酶的纯化及性质研究   总被引:12,自引:0,他引:12  
将产热稳定性过氧化氢酶的重组大肠杆菌培养后菌体破碎得到的粗酶液经热处理、硫酸铵分级沉淀、DEAE\|Sephadex A\|50离子交换层析、HiPrep16/10 Phenyl疏水作用层析、Superdex200 HR 10/30凝胶层析提纯后得到电泳纯的酶,比酶活达到15629U/mg。此酶的最适温度为70℃,最适pH70,在60℃保温60min酶活力基本不变,在pH3~8的范围内比较稳定。此酶的Km和Vmax分别为775mmol/L和278mmol\5min\+\{-1\}·mg-1。1mmol/L的Zn2+、Ba2+、Mn2+可使该酶完全失活,KCN、NaN\-3、Na\-2S\-2O\-4、巯基乙醇对酶活力有抑制作用,50mmol/L的EDTA不影响酶活性。  相似文献   
909.
Zhang L  Zhang H  Zhao Y  Mao F  Wu J  Bai B  Xu Z  Jiang Y  Shi C 《DNA and cell biology》2012,31(2):171-179
Autophagy plays specific roles in host innate and adaptive immune responses to numerous intracellular pathogens, including Mycobacterium tuberculosis. The ESAT-6 and CFP-10 proteins are secreted by M. tuberculosis and play important roles in pathogenesis. We hypothesized that these two proteins may affect the autophagy function of host macrophages during infection with M. tuberculosis, thereby shaping the immune reaction toward the pathogen. Interestingly, we found that rapamycin-induced autophagy of macrophages infected with M. tuberculosis H37Rv enhanced localization of mycobacteria with autophagosomes and lysosomes. Ectopic expression of the ESAT-6/CFP-10 fusion in macrophages dramatically inhibited autophagosome formation, and M. tuberculosis survival inside infected macrophages was significantly affected as well. Further, M. tuberculosis viability was increased by the fusion protein. Expression levels of autophagy-related genes (ATG), especially atg8, also decreased (p<0.05). These results suggested that ESAT-6 and CFP-10 proteins play significant roles in autophagy formation in M. tuberculosis infection and that autophagosome formation is regulated through the expression of ATG.  相似文献   
910.
A hybrid anaerobic solid-liquid bioreactor for food waste digestion   总被引:5,自引:0,他引:5  
A hybrid anaerobic solid-liquid (HASL) bioreactor is an enhanced two-phase anaerobic system, that consists of a solid waste reactor as the acidification reactor and a wastewater reactor, i.e. an upflow anaerobic sludge blanket (UASB) reactor as the methanogenic reactor. Food waste digestion in HASL bioreactors with pre-acidification and HASL operation stages was investigated in two separate runs. After 8 days of pre-acidification in Run A and 4 days in Run B, total volatile fatty acid (TVFA) and chemical oxygen demand (COD) concentrations in the leachates of both acidification reactors were similar. During HASL operation stage, TVFA and COD removal in the methanogenic phase were 77–100% and 75–95%, respectively. Some 99% of the total methane generated was from the methanogenic phase with a content of 68–70% methane. At the end of operation, about 59–60% of the added volatile solids (VS) were removed with a methane yield of 0.25 l g–1 VS.  相似文献   
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