Analysis of hippocampal gene expression profile of Alzheimer's disease model rats using genome chip bioinformatics

In this study, an Alzheimer＇s disease model was established in rats through stereotactic injection of condensed amyloid beta 1-40 into the bilateral hippocampus, and the changes of gene expression profile in the hippocampus of rat models and sham-operated rats were compared by genome expression profiling analysis. Results showed that the expression of 50 genes was significantly up-regulated （fold change 〉 2）, while 21 genes were significantly down-regulated in the hippocampus of Alzheimer＇s disease model rats （fold change 〈 0.5） compared with the sham-operation group. The differentially expressed genes are involved in many functions, such as brain nerve system development, neuronal differentiation and functional regulation, cellular growth, differentiation and apoptosis, synaptogenesis and plasticity, inflammatory and immune responses, ion channels/transporters, signal transduction, cell material/energy metabolism. Our findings indicate that several genes were abnormally expressed in the metabolic and signal transduction pathways in the hippocampus of amyloid beta 1 40-induced rat model of Alzheimer＇s disease, thereby affecting the hippocampal and brain functions.

多房棘球蚴主要卵抗原p40-1的原核表达、多克隆抗体制备及其组织定位

初步确定MEAp40-1的基因特征及其组织分布特征。根据WormBase数据库中多房棘球蚴MEAp40-1序列设计特异性引物,利用RT-PCR技术扩增MEAp40-1编码基因并构建重组表达质粒pET-28a-MEAp40-1,IPTG诱导表达并用His-Ni亲和层析柱纯化,制备多克隆抗体。通过间接ELISA方法检测多克隆抗体效价,应用免疫荧光技术定位MEAp40-1在原头蚴中的分布。通过生物信息学分析发现,多房棘球绦虫表达3种不同的MEAp40(MEAp40-1~3),分别分布在不同染色体上。系统进化树显示,每个多房棘球绦虫MEAp40基因与其相应的细粒棘球绦虫的同源基因组成一支。多房棘球绦虫MEAp40-1编码基因全长945 bp,编码314个氨基酸。7种绦虫的MEAp40-1蛋白很保守,均存在α晶体结构域,并且位于该结构域中的协同分子伴侣结合位点也非常保守。MEAp40-1重组蛋白大小约为37 ku,其多克隆抗体效价可达1∶409 600,可识别虫体中的MEAp40-1天然蛋白。MEAp40-1蛋白主要分布在多房棘球蚴后端,而头节、囊壁等其他部位均未见表达。结合以上研究结果,推测MEAp40-1蛋白在绦虫中的生物学功能保守,可能与多房棘球绦虫原头蚴的发育有关。