双价外壳蛋白基因植物表达载体的构建及马铃薯转基因植株的鉴定

在克隆了马铃薯Ｘ病毒（ＰＶＸ）、马铃薯Ｙ 病毒（ＰＶＹ）和马铃薯卷叶病毒（ＰＬＲＶ）的外壳蛋白基因的基础上,构建同时包含ＰＶＸ和ＰＶＹ 与ＰＶＹ 和ＰＬＲＶ 两个外壳蛋白基因植物表达框架的表达载体,通过农杆菌（Ａｇｒｏｂａｃｔｅｒｉｕｍ ｔｕｍｅｆａｃｉｅｎｓ）介导转化烟草（Ｎｉｃｏｔｉａｎａｔａｂａｃｕｍ ）和生产上常用的几个马铃薯（Ｓｏｌａｎｕｍ ｔｕｂｅｒｏｓｕｍ ）优良品种：“Ｆａｖｏｒｉｔａ”、“虎头”、“克４”。经ＰＣＲ检测证明外源基因已整合到植物的染色体上,得到批量转基因植株。在转ＰＶＸ＋ＰＶＹ 外壳蛋白基因的烟草上接种ＰＶＸ （５ μｇ／ｍ Ｌ）、ＰＶＹ（２０ μｇ／ｍ Ｌ）病毒,得到有一定抗性的植株     

生物素标记HBV RNA探针的制备及应用

本文首次采用ＳＰ６５特殊质粒与人类的乙型肝炎病毒ＤＮＡ重组,制备了Ｂｉｏ－ＨＢＶ ＲＮＡ探针,能特异地与ＨＢＶ ＤＮＡ杂交,将该探针与缺口转移方法标记的Ｂｉｏ－ＨＢＶ ＤＮＡ探针进行了比较,结果显示出Ｂｉｏ－ＨＢＶ ＲＮＡ探针比Ｂｉｏ－ＨＢＶ ＤＮＡ探针的敏感性提高１０倍,并分别应用两种探针同时检测７０例乙肝病人血清中ＨＢＶ ＤＮＡ,阳性率各为３１．４２％、２８．５７％（Ｐ＞０．２５）。对Ｂｉｏ－     

A tightly associated serine/threonine protein kinase regulates phosphoinositide 3-kinase activity.

We identified a serine/threonine protein kinase that is associated with and phosphorylates phosphoinositide 3-kinase (PtdIns 3-kinase). The serine kinase phosphorylates both the 85- and 110-kDa subunits of PtdIns 3-kinase and purifies with it from rat liver and immunoprecipitates with antibodies raised to the 85-kDa subunit. Tryptic phosphopeptide maps indicate that p85 from polyomavirus middle T-transformed cells is phosphorylated in vivo at three sites phosphorylated in vitro by the associated serine kinase. The 85-kDa subunit of PtdIns 3-kinase is phosphorylated in vitro on serine at a stoichiometry of approximately 1 mol of phosphate per mol of p85. This phosphorylation results in a three- to sevenfold decrease in PtdIns 3-kinase activity. Dephosphorylation with protein phosphatase 2A reverses the inhibition. This suggests that the association of protein phosphatase 2A with middle T antigen may function to activate PtdIns 3-kinase.     

肝胆显像螯合物—氮基三乙酸单酰苯胺及其类似物的合成

本课题合成四个氮基三乙酸单酰苯胺(IDA)类及其类似物肝胆显像螯合物。(1)用家兔做了肝胆显像扫描实验,其显像效果较好。(2)～(3)为未见报道的化合物。     

大鼠肝癌中α_2-巨球蛋白等几种分泌性蛋白基因表达的变化

用Northern blot方法对二乙基亚硝胺所诱发的大鼠肝癌中内源性蛋白酶抑制因子α_2-巨球蛋白(α_2-M)、非特异性免疫抑制剂α_1-酸性糖蛋白(α_1-AGP)及雄性激素正调控的α-2u球蛋白(α-2u)三种分泌性蛋白基因表达情况进行了分析。结果表明在大部分(14/16)肝癌样品中α_2-M RNA水平显著降低;而α_1-AGP RNA水平显著高于正常对照水平;α-2u RNA水平明显下降,但在某些雄性大鼠肝癌样品中该基因却有一定程度的表达。这些结果说明,一些肿瘤宿主血浆中α_2-M水平的显著下降及α_1-AGP水平的明显升高分别是由于基因表达活性的下降及升高所致。α-2u基因表达的异常提示,在癌变过程中机体的内分泌功能发生了某些变化。     

Identification of tyrosines 154 and 307 in the extracellular domain and 653 and 766 in the intracellular domain as phosphorylation sites in the heparin-binding fibroblast growth factor receptor tyrosine kinase (flg).

Four tyrosine residues have been identified as phosphorylation sites in the tyrosine kinase isoform of the heparin-binding fibroblast growth factor receptor flg (FGF-R1). Baculoviral-insect cell-derived recombinant FGF-R1 was phosphorylated and fragmented with trypsin while immobilized on heparin-agarose beads. Phosphotyrosine peptides were purified by chromatography on immobilized anti-phosphotyrosine antibody and analyzed by Edman degradation and electrospray tandem mass spectrometry. Tyrosine residue 653, which is in a homologous spatial position to major autophosphorylation sites in the catalytic domain of the src and insulin receptor kinases, is the major intracellular FGF-R1 phosphorylation site. Residue 766 in the COOH-terminus outside the kinase domain is a secondary site. Tyrosine residues 154 and 307, which are in the extracellular domain of transmembrane receptor isoforms and are in an unusual sequence context for tyrosine phosphorylation, were also phosphorylated.     

真菌诱导子对悬浮培养西洋参细胞的生理效应

报道了不同真菌诱导子对悬浮培养的西洋参（Ｐａｎａｘｑｕｉｎｑｕｅｆｏｌｉｕｍ）细胞生长、皂甙和多糖合成,以及细胞内和培养液中过氧化物酶活性的生理效应。悬浮培养的西洋参细胞经刺盘孢菌（Ｃｏｌｌｅｔｏｔｒｉｃｈｕｍｎｉｃｏｌｔｉａｎａｅ）丝体诱导子处理后,总皂甙产率可由对照的２９６ｍｇ／Ｌ增加到６７９ｍｇ／Ｌ（约占细胞干重的（１６．３％）,比对照提高约１．３倍,而且总皂甙的８５％排放在培养液中;经黑曲霉（Ａｓｐｅｒｇｉｌｌｕｓｎｉｇｒａｎ）诱导子处理后,细胞多糖含量可达到１１．７９％（细胞干重）,比对照增加１倍多。初步纯化的刺盘孢菌丝体诱导子和尖孢镰刀菌（Ｆｕｓｕｒｉｕｍｏｘｙｓｐｏｒｕｍ）滤液诱导子在诱导处理前期能明显促进西洋参细胞生长,同时细胞内及培养液中过氧化物酶活性显著增加;随时间延长,细胞生长和酶活性逐步受到抑制。     

A difference in the affinity labeling of Ca2+, Mg2+-activated ATPases of normal and unc A strains of Escherichia coli by the 2',3'-dialdehyde derivative of adenosine 5'-diphosphate

The 2′,3′-dialdehyde of ADP, obtained by periodate oxidation of ADP, inhibited the hydrolytic activity of the purified Ca²⁺, Mg²⁺-activated ATPase of $\text{Escherichia}\text{coli}$. In the initial stages of the reaction inhibition was due to the reaction of 1 mol inhibitor/active site. When non-specific labelling of amino groups by the dialdehyde was lowered by the simultaneous presence of 15 mM ATP in the reaction mixture, 3 mol “ATP-protectable” binding sites/mol ATPase were found. “ATP-protectable” binding of the dialdehyde was not observed when the hydrolytically inactive ATPase of an $\text{unc A}$ mutant of $\text{E.}\text{coli}$ was used although binding of the inhibitor to non-protected amino groups still occurred. This suggests that the mutant ATPase is unable to bind ATP or that the amino groups with which the dialdehyde reacts in the native enzyme are absent or masked.