Analysis of cDNA sequence, protein structure and expression of parotid secretory protein in pig

Parotid secretory protein (PSP) secreted abundantly in saliva, whose function is related with the anti-bacterial effect. The PSP cDNA has been isolated from pig parotid glands by 3′ and 5′ rapid amplification of cDNA end (RACE), based on the conserved signal peptide region among the known mammalian PSP. The result of homologous comparison shows that pig PSP and human PSP shares the high identity at the level of the primary, secondary and tertiary protein structure. A search for functionally significant protein motifs revealed a unique amino acid sequence pattern consisting of the residues Leu-X(6)-Leu-X(6)-Leu-X(7)-Leu-X(6)-Leu-X(6)-Leu near the amino-terminal portion of the protein, which is important to its function. RT-PCR, Dot blot and Northern blot analysis demonstrated that PSP was strongly expressed in parotid glands, but not in other tissues.     

Inhibitory effect of the adenovirus type 5 E1A protein expressed in the yeast system of the human tumor cell growth

Adenovirus 5 type E1A as a tumor suppressor gene can inhibit tumor growth and enhance the censitivity of chemotherapy and radiotherapy.E1A have the ability to integrate into the host genome,resulting in long-time expres-sion that induces Rb gene inactivation and animal cells im-mortalization.This prompted us to select the E1A protein for treatment of cancer in order to overcome the limitations of E1A gene therapy.Thus,we firstly comstructed E1A eu-caryotic expression vector (pPIC9/E1A),transformated the pichia pastoris yeast cells(GS115) and screened the high-expressing recombinant strains.The positive yeast strains were cultured in the shake flask,and induced for 3d.The crude E1A protein was purified using two steps of col-umu chromatography on HiTrap Q and HiTrap SP.The pu-rified E1A protein was identified by SDS-PAGE and Western blot.E1A protein was mostly located at cellular unclear when Cheriot delivered E1A protein into cells.The analysis in vitro indicated that the E1A protein arrested LN686 cell cycle at G2/M phase,and significantly inhibited the growth of LN686 tumor cells.The current studies firstly provided an experimental basis to further develop E1A protein for tumor treatment.     

CDMA通信系统接收信号的统一表达式

针对同步与异步CDMA通信系统以及不同的信道模型,给出了连续接收信号的统一表达式。若对接收信号进行采样,也可得到离散接收信号的统一表达式。通过给出信道模型的统一表达式,可以很方便地利用此表达式来进行CDMA无线通信系统的各种复杂信道的参数辩识以及盲均衡设计。     

建筑、结构、表现形式的有机融合--迁安综合体育馆建筑设计

结合迁安体育馆方案设计,对小型体育馆的总体平面设计、建筑平面设计、建筑立面造型设计、体育馆结构设计、音质和照明设计等方面进行了探讨,并在小型体育馆建筑设计、结构设计以及表现形式的有机融合方式方面进行了综合探索.     

在心脏组织表达的一个人类新基因

KRAB／C2H2型锌指蛋白是一类具有重要功能的转录调节因子，初步克隆了一个新的人类KRAB／C2H2型锌指蛋白基因，经国际基因命名委员会批准命名为ZNF382，此基因长2824bp，含5个外显子，4个内含子，在基因组DNA上长约23kb，它编码548个氨基酸，在氮末端含一个KRAB框，碳末端含一个未成形的锌指(VZF)和9个锌指(ZF)，Northern杂交结果表明，ZNF382mRNA在早期胚胎时期(至少在妊娠34d之前)就开始表达，在不同时期人类胚胎组织中广泛表达，包括小脑、肾、大脑、肺、心脏、骨骼肌、舌和肾上腺，在成人组织其表达限制在心脏，其结构和表达特征预示着ZNF382在心脏发育和功能的发挥起着潜在的作用。     

纳豆激酶基因克隆及其在大肠杆菌中活性表达研究

以纳豆芽孢杆菌基因组DNA为模板，PCR扩增了纳豆激酶基因（natto kinase gene）中编码前肽、成熟肽的核苷酸序列（pro-NK），构建大肠杆菌表达质粒pTYB102，转化大肠杆菌ER2566。在IPTG诱导下，分别在15℃（14h）、30℃（3h）、37℃（2h）条件下培养，pTYB102均能表达出有活性的纳豆激酶。实验证实纳豆激酶基因得到活性表达需要Pro序列。SDS－PAGE表明，15℃和30℃和37℃培养表达的杂蛋白更少。薄层扫描测定表达的纳豆激酶占菌体总蛋白30％以上。     

电针对佐剂性关节炎大鼠炎症局部阿片肽基因表达的影响

以佐剂性关节炎大鼠为炎症痛模型，选择悬钟，昆仑穴位，采用原位杂交组织化学方法，观察电针（ＥＡ）对大鼠炎症局部阿片肽前体物质前阿黑皮素（ＰＯＭＣ）和前脑啡肽原（ＰＥＮＫ）ｍＲＮＡ的表达，结果ＥＡ可以促进炎症局部免疫细胞中ＰＯＭＣ和ＰＥＮＫ ｍＲＮＡ的表达，使阿片肽的合成和释放增加，以实现外周炎症局部的镇痛作用。     

气相色谱填充柱改装成毛细管柱的研究

针对上分103型气相色谱仪，改装填充柱为毛细管柱后其性能良好，各项指标均达到同类仪器水平。     

纤维素酶的研究概况

本文着重介绍了纤维素酶的组成、分子结构、基因表达及研究趋向和应用前景，提出了在纤维素酶研究中必须解决的一些问题。纤维素酶的研究为纤维素的充分利用开辟了一条新的途径。