EXPRESSION OF THE PLASMODIAL NUTRIENT CHANNEL ON OOCYTES

这是一项分离和表征营养渗透离子的建议。 在红细胞内疟疾寄生虫恶性疟原虫上的通道。这 渠道首先由申请人和他的同事描述[1， 附录]可能是寄生虫生存所必需的，因为它允许 从红血中获取氨基酸和单糖的寄生虫 细胞(RBC)。 该通道是通过膜片钳方法测量离子来识别的 寄生虫液泡膜(PVM)上的通道活动 围绕着寄生虫的两层膜。申请人现建议： 通过显微注射寄生虫在非洲爪哇卵母细胞上表达该通道 MRNA.表达的通道将被用来测量钾、乳酸和 ATP4-通透性，检查通道调节，并研究可能 拦截者。如果在卵母细胞上表达不成功，另一种选择 方法，重组成脂质双分子层，将允许同样详细 人物刻画。这些研究应解决以下基本问题 寄生虫营养物质的贩运，可能对 疟疾的治疗：已确定的通道阻滞剂可能会阻止营养 获取，因此，通过饥饿杀死寄生虫。 申请人已决定将他的长期研究努力集中在 原生生物在红细胞内存活的机制。他有相当多的 使用研究膜转运和Will的方法的经验， 这一奖项，奠定了分子生物学方法的基础。

This is a proposal to isolate and characterize the nutrient-permeable ion channel on the intraerythrocytic malaria parasite, P. falciparum. This channel was first described by the applicant and his colleagues [1, appendix] and may be essential for parasite survival because it permits the parasite to acquire amino acids and monosaccharides from the red blood cell (RBC). This channel was identified by using the patch clamp method to measure ion channel activity on the parasitophorous vacuole membrane (PVM), the outer of two membranes surrounding the parasite. The applicant now proposes to express this channel on Xenopus oocytes by microinjection of parasite mRNA. Expressed channels will then be used to measure K+, lactate, and ATP4- permeabilities, examine channel regulation, and investigate possible blockers. If expression on oocytes is unsuccessful, an alternative approach, reconstitution into lipid bilayers, will allow the same detailed characterization. These studies should address fundamental questions on parasite nutrient trafficking and may have profound implications for the treatment of malaria: an identified channel blocker may prevent nutrient acquisition and, therefore, kill parasites through starvation. The applicant has decided to focus his long-term research efforts on the mechanisms of plasmodial survival within the RBC. He has considerable experience with methods used to study membrane transport and will, with this award, develop a foundation in the methods of molecular biology.