Primary study on trans-activation ability of hepatitis B virus envelope proteins

目的构建系列含乙型肝炎病毒(HBV)表面抗原前-前-S区的酵母细胞表达质粒,初步探讨表达蛋白是否具有反式激活作用。方法用多聚酶链反应(PCR)扩增含前-前-S区的全S、S2和S基因,定向克隆于pDEST32载体,进行序列测定,重组质粒命名为pDEST32-wS、pDEST32-pS2和pDEST32-SHBs。用乙酸锂转化法将重组质粒转化酵母菌MaV203,经Western blot和胶体金法验证重组质粒在酵母细胞中的表达。以酵母双杂交法将重组质粒和载体pDEST22共同转入酵母菌MaV203,并在SC/-leu/-trp/-his三缺培养基及不同浓度梯度3AT培养基中验证自激活。结果重组质粒pDEST32-wS经序列测定含有HBV自前-前-S至主蛋白基因序列。经Western blot和胶体金法证实转染的酵母细胞可表达表面抗原蛋白。pDEST32-wS与pDEST22共转染实验证实被转染酵母细胞不能在浓度30 mmol/L以上的3AT培养基生存。结论构建了pDEST32-wS、pDEST32-pS2和pDEST32-SHBs表达载体,pDEST32-wS和pDEST32-SHBs在酵母细胞中可表达HBsAg... 【英文摘要】 Objective To construct yeast expression vector of HBV whole-S gene including pre-pre-S region and explore the trans-activation function of whole-S protein.Methods Whole-S gene,pre-pre-S to pre-S2 region and major HBsAg coding region containing Not I and Sal I endoenzyme sites were obtained by PCR method.After enzyme digestion,PCR products were cloned into yeast expression vector pDEST32.Recombinant plasmids were sequenced and named as pDEST32-wS,pDEST32-pS2 and pDEST32-SHBs,respectively.Recombinant plasmids...厦门市首批重大疾病科研攻关项目(WKZ0501);; 厦门市卫生局医学科研立项项目(WSK0506);; 厦门大学引进人才科研启动基金(Z03109);; 福建省青年科技人才创新项目(2006F3127);; 福建省青年科技人才创新项目(2006F3127

Ar离子辐照非晶态合金表面发泡和针孔形成研究

１５０ｋｅＶ和１９５ｋｅＶＡｒ离子室温下辐照非晶态合金（Ｃｏ９４Ｆｅ４Ｃｒ２）７８Ｓｉ８Ｂ１４，表表面发泡和溅射腐蚀是两种主要的表面损伤过程．针孔出现较表面发泡要晚，它的密度随剂量增加迅速地增加，并且在一定的辐照剂量时趋向饱和，这时，一种多孔粗糙的表面损伤结构形成．针孔的形成影响了表面发泡，导致了发泡密度随剂量增加急剧地减小．用溅射和气泡破裂解释了针孔形成和在高剂量时趋向饱和的原因．Amorphous alloy (Co94Fe4Cr2)78Si8B14 was bombarded with argon ions at energies of150keV and 195keV respectively. Above a critical fluence blistering and sputteringerosion were the two main surface damage phenomena. The critical fluence for onsetof pinhole formation was determined and found to increase with ion energy. Thedensity of pinhole increases with ion fluence dramatically and at a certain fluence, itreaches saturation. However, with the formation of pinhole, the density of blisterdecreases rapidly an...国家自然科学基金,甘肃省自然科学基

Ar离子辐照的非晶态合金表面发泡扫描电镜观测

１５０、１９５和３００ｋｅＶＡｒ离子在室温下辐照非晶态合金Ｃｏ７０．２Ｆｅ３．９Ｎｂ３．９Ｓｉ１４Ｂ８和Ｃｏ６６Ｆｅ４．５Ｖ２．２５Ｎｉ２．２５Ｓｉ１０Ｂ１５，扫描电镜在一定的辐照剂量范围观测到了表面发泡形成，发泡形成的临界剂量和直径随离子能量增加而增加。Ａｒ离子能量高于１９５ｋｅＶ时，发泡和发泡破裂是主要的表面损伤现象，而在１５０ｋｅＶＡｒ离子辐照下，未观测到发泡破裂。使用Ａｒ离子的聚集、临界气压的建立和气体从近表面的释放解释了表面发泡效应。Surface blistering of the amorphous alloys Co70.2Fe3.9Nb3.9Si14B8and Co66Fe4.5V2.25Ni2.25Si10B15 due to argon ion bombardment at energies of 150,195 and 300 keV has been observed with a scanning electron microscope(SEM).The critical dose for onset of blistering and the blister diameter are determined and found to increase with increasing projectile energy. Above about 195 keV, blisters and rupture of blisters are the predominant surface damage phenomena. However,at 150 keV, there is no evidence of cracked国家自然科学基金,甘肃省自然科学基金,中国科学院重点基

195KeV Ar~＋辐照非晶态合金表面损伤形貌的研究

用扫描电子显微镜观测研究了室温下１９５ｋｅＶＡｒ＋辐照非晶态合金Ｃｏ（６０）Ｆｅ（１２）Ｎｉ（１０）Ｓｉ６Ｂ（１２）和Ｆｅ（３９）Ｎｉ（３９）Ｖ２Ｓｉ（１２）Ｂ８在各剂量阶段的表面损伤形貌。结果表明，表面损伤是发泡和溅射相互竞争的过程。低剂量下，表面损伤以发泡为主；而在高剂量时，表面发泡消失，溅射造成的多孔粗糙表面损伤结构形成。对高剂量时表面发泡消失的可能机制作了探讨。The dependence of surface damage of amorphous alloys Co60Fe12Ni10Si6B12 and Fe39Ni39V2Si12B8 irradiated with 195keV argon ions on the ion dose has been investigated by using scanning electron microscope.Surface damages such as blistering and sputtering were observed.At low dose blistering was dominant, but at higher dose blisters disappered and a porous structure was developed as the result of sputtering.The reasons for disappering of blisters at high dose were also discussed in detail.国家自然科学基金,甘肃省自然科学基

植物种子发育的分子机理

种子作为高等植物有性生殖的产物,不仅是植物繁育的最主要形式,也是人类赖以生存的粮食的最主要来源。在被子植物的有性生殖过程中,来自花粉的两个精子分别与胚囊中的卵细胞和中央细胞融合形成合子和初生胚乳核。前者经过细胞分裂、分化、器官发生和休眠建立等过程形成胚胎;后者经过游离核分裂、细胞化等过程形成胚乳。一个完整的胚胎具有子叶、胚轴、茎尖和根尖分生组织等结构。在种子发育和萌发过程中,胚乳为胚胎提供营养。胚胎和胚乳均可作为植物的营养累积器官,在发育后期累积淀粉、脂肪酸或/和蛋白质等。毫无疑问,受精后的胚胎与胚乳发育不仅是高等植物生活周期的一个重要环节,也是作物产量和品质决定的最关键时期。这一过程所涉及的细胞分裂、细胞分化、器官发生和胞间通信等过程的调控机制是生命科学领域的重大科学问题,也是发育生物学研究的核心命题。相关研究不仅为揭示种子形成的调控机理提供重要线索,也将为农作物的产量和品质提高提供新的技术手段。本文将重点阐述种子研究的重要性、国内外相关研究进展和未来发展前景