PROTEIN TARGETING TO THE TOXOPLASMA GONDII PLASTID

在艾滋病患者的机会性感染中， 两种相关的寄生虫：刚地弓形虫和微小隐孢子虫。 这两种生物都属于顶复门， （包括疟疾的病原体）最近被证明 含有一种独特的类质体细胞器。 因为人类没有 作为一种同源的细胞器，质体可以为细胞提供一个独特的靶点。 开发专门针对这些寄生虫的药物。 然而，对这种质粒的蛋白质成分知之甚少 或其功能。 T.弓形虫是唯一的顶复门寄生虫， 遗传学方法已经发展完善。 这份提案描述了一项计划， 检查顶复门质体的蛋白质定位 利用T.弓形虫作为我们的模型 我们将获得整个 预测指定核编码质体的cDNA编码区 蛋白 然后我们将验证该蛋白质确实是质体 常驻，使用表位标记/转染方法。 最后我们 将确定质体蛋白的序列是否可以通过 报告分子到质体。这些研究将首次提供 关于顶复门质体的生物起源的信息， 研究质体功能的基础。

Among the opportunistic infections in AIDS patients are those caused by two related parasites: Toxoplasma gondii and Cryptosporidium parvum. Both organisms belong to the phylum Apicomplexa, whose members (including the causative agent of malaria) have recently been shown to contain a unique plastid-like organelle. Because humans do not have a homologous organelle, the plastid may provide a unique target for the development of drugs that act specifically against these parasites. However, little is known about the protein constituents of this plasmid or its function. T. gondii is the only apicomplexan parasite for which genetic approaches are well-developed. This proposal describes a plan to examine the localization of proteins to the apicomplexan plastid using T. gondii as our model. We will obtain the sequence of the entire coding region of a cDNA predicted to specify a nuclearly encoded plastid protein. We will then verify that the protein is indeed a plastid resident, using an epitope tagging/transfection approach. Finally we will determine if sequences from the plastid protein can route a reporter molecule to the plastid. These studies will provide the first information about the biogenesis of the apicomplexan plastid and lay the groundwork for studying plastid function.