人新基因hbrp的染色体定位及其对TPK活性的抑制作用（简报）

hbrp(Human BSP-Related Protein)是我们实验室最近在睾丸组织中克隆的一个人与BSP（bovine seminal plasma)蛋白相关的新基因。为了将有关该新基因信息与现有人类基因组转录图相整合,我们应用荧光原位杂交(fluorescent in situ hybridizationFISH)法进行了该基因的人染色体基因定位,结果成功地将hbrp基因定位在人19号染色体长臂1区3带上。hbrp基因是在对BSP蛋白功能的研究过程中发现并克隆的,其同源性分析发现,与其序列最相近     

人源性抗HBsAg抗体Fab段在酵母中的表达

通过分步整合的方式,将人源性抗乙肝表面抗原（HBsAg）抗体Fab的轻、重链基因分步整合到巴斯德毕赤（Pichia pastoris）酵母GS115菌株的染色体上,经甲醇诱导,成功地分泌表达出抗HBsAg抗体的Fab片段,表达量达50～80mg/L。ELISA结果显示重组酵母分泌表达出的Fab具有较强的结合HBsAg的能力。通过抗Fab的抗体柱亲和层析,纯化出了纯度较高的Fab产品。     

Ligation or cross-linking of CD40 has different effects on AGS gastric cancer cells

A gastric cancer (GC) cell line, AGS, has high-level expression of CD40, a tumor necrosis factor receptor (TNFR) family member. CD40 is present on the surfaces of a large variety of cells, including B cells, endothelial cells, dendritic cells and some carcinoma cells, and delivers signals regulating diverse cellular responses, such as proliferation, differentiation, growth suppression, and cell death. In this research, we studied the effects of different forms of CD40 stimulation on AGS cells by flow cytometry, Western blotting and siRNA transfection. We found that different forms of CD40 stimulation, either recombinant soluble CD40L (sCD40L, ligation) or agonist anti-CD40 antibody (cross-linking), induced different effects in AGS gastric cancer cells, proliferation or apoptosis. We also showed that VEGF provided a significant contribution to sCD40L-induced proliferation, while agonist anti-CD40 antibody induced GADD45 upregulation and promoted apoptosis.     

罗布麻对不同浓度盐胁迫的生理响应

利用网室盆栽实验,研究不同浓度的NaCl（100-400mmol·L^-1）胁迫对罗布麻（Apocynum venetum）生长及生理特性的影响。结果表明,100mmol·L^-1NaCl处理显著降低了罗布麻植株的鲜重,但对其干重影响不大;随着盐浓度继续增加,罗布麻鲜重和干重显著下降。在盐胁迫下,罗布麻叶片内的丙二醛含量、电解质渗漏率、根部和地上部Na^＋的含量明显增加,K^＋的含量随着盐离子浓度的增加而降低。盐胁迫显著降低了地上部Ca^2＋的含量,而对根部Ca^2＋的含量没有影响。植株K^＋/Na^＋和Ca^2＋/Na^＋比值随着盐胁迫强度的增加而降低。盐胁迫显著促进了罗布麻根部对K^＋和Ca^2＋的选择性吸收及对K^＋的选择性运输。当NaCl浓度小于或等于200mmol·L^-1时,随着盐离子浓度的增加,罗布麻叶片内的脯氨酸和可溶性糖积累显著增加,而当NaCl浓度大于200mmol·L^-1时,这2种有机溶质含量显著下降。总体上,罗布麻通过积累无机离子、合成有机溶质及维持较高的K^＋、Ca^2＋选择性吸收和运输来适应一定浓度（≤200mmol·L^-1NaCl）的盐胁迫。     

红色诺卡菌固体培养基配方的优化

应用响应面优化设计法优化固体培养基配方,增大红色诺卡菌的固体培养细胞生物量。首先用Plackett-Burman法从现有培养基组分中找到影响红色诺卡菌细胞生物量的关键因素,再通过最陡爬坡法确定细胞生物量最大的配方,用作中心组合设计(Central Composite Design, CCD)实验的基础起始值,拟合数学模型方程,最后找到最优组分的组合。优化的配方转移至企业实施放大实验,对结果进行验证和比较。试验结果表明,培养基各组分中影响红色诺卡菌细胞生物量的关键因素为蛋白胨、NaCl、牛肉膏;最优固体培养基配方:蛋白胨42 g/L、牛肉膏8 g/L、NaCl 1.2 g/L、甘油10 mL/L、Na_2HPO_4·12H_2O 0.3 g/L、琼脂20 g/L。在细胞生物量方面最优固体培养基配方比原配方高104%。响应面优化设计可用于提高红色诺卡菌细胞生物量固体培养基的优化,也为红色诺卡菌培养条件、液体发酵的优化研究提供参考。     

白念珠菌钙稳态系统及钙信号途径的研究进展

白念珠菌是临床重要的条件致病菌,其胞内的钙稳态及钙信号途径与宿主侵染、压力应答等诸多生理过程紧密相关。研究该菌的钙稳态系统及钙信号调控网络,对明确白念珠菌的侵染机制与耐药机理,以及开发具有新靶点的抗真菌药物具有重要意义。本文对这些内容的研究进展进行了综述。     

双歧杆菌脂磷壁酸对B16荷瘤小鼠NK细胞受体NKG2D及其配体的影响

目的探讨双歧杆菌脂磷壁酸（LTA）对黑色素瘤B16荷瘤小鼠NK细胞受体NKG2D及其配体的影响。方法将黑色素瘤B16细胞接种于C57BL／6小鼠皮下,待触及肿块后于荷瘤小鼠皮下注射双歧杆菌LTA。采用MTT、流式细胞术（FCM）、RT-PCR方法分别检测经双歧杆菌LTA处理后B16荷瘤小鼠NK细胞杀伤活性、NK细胞NKG2D受体蛋白表达以及肿瘤组织内Rae-1、H60 mRNA表达的变化。结果与对照组相比,经双歧杆菌LTA处理后,B16荷瘤小鼠的NK细胞杀伤活性增强（P〈0．05）,NK细胞受体NKG2D表达明显增加（P〈0．05）,肿瘤组织Rae-1、H60 mRNA表达上升（P〈0．05）,并具有浓度依赖性。结论双歧杆菌LTA能够增强B16荷瘤小鼠NK细胞的杀伤活性,其机制可能与上调NK细胞受体NKG2D的蛋白表达和肿瘤组织Rae-1、H60 mRNA的表达有关。     

Isolation and identification of canine parvovirus serotype 2a and its VP2 protein expression in transgenic tobacco

A strain of canine parvovirus (CPV) was isolated from feces of an ill puppy in an animal hospital in Wuhan, China. It was designated as CPV/WH02/06. This isolate was identified as serotype CPV-2a by the hemagglutination test, CPV Ag detection strip, electron microscopy, and PCR. The vp2 gene was cloned and sequenced and assigned GenBank accession number EU377537. A 1242 bp segment of the 5' region of the vp2 gene was cloned and inserted into the binary vector pBI121 and used for Agrobacterium-mediated tobacco transformation. Transgenic tobacco plants were selected on MS medium supplemented with 100 μg/mL kanamycin and 100 μg/mL timentin. Integration of the vp2 gene into the tobacco genome was confirmed by PCR using T1 progeny plants, and the expression of the VP2 protein was confirmed by Western blotting.     

A ubiquitin-like protein unleashes ubiquitin ligases

Modification of cullin-RING ubiquitin ligases by the ubiquitin-like molecule Nedd8 promotes substrate ubiquitination. A crystal structure of a cullin modified by Nedd8 recently reported in Cell (Duda et al., 2008) and a biochemical study in Molecular Cell (Saha and Deshaies, 2008) reveal the dramatic impact on the ligase machinery by conjugation of ubiquitin or ubiquitin-like proteins.     

利用酵母双杂交系统筛选与黄瓜花叶病毒外壳蛋白互作的寄主蛋白

利用酵母双杂交系统,以黄瓜花叶病毒(Cucumber mosaic virus,CMV)的外壳蛋白(coat protein,CP)为诱饵,从番茄叶片c DNA文库中筛选与其互作的蛋白。结果显示,诱饵载体pBT3-SUC-CMV-CP均能在酵母细胞中正确表达,无自激活活性而且对酵母无毒性;通过对酵母双杂交文库的筛选和回转验证,共获得了98个阳性克隆,分别编码67个可能与CMV-CP相互作用的蛋白,分别参与植物防御反应、光合作用、物质转运、信号转导、能量代谢、氨基酸代谢、细胞壁的形态建成、植物的激素代谢等。本研究结果表明,CMV CP可同时调控寄主的多个代谢过程,在CMV的致病过程中有多重功能。