INSERM-EPFL Joint Laboratory, Global Health Institute, EPFL-SV-GHI, Station 19, CH-1015 Lausanne, Switzerland.
Mol Microbiol. 2011 Jan;79(1):205-21. doi: 10.1111/j.1365-2958.2010.07442.x. Epub 2010 Nov 10.
Aurora kinases compose a family of conserved Ser/Thr protein kinases playing essential roles in eukaryotic cell division. To date, Aurora homologues remain uncharacterized in the protozoan phylum Apicomplexa. In malaria parasites, the characterization of Aurora kinases may help understand the cell cycle control during erythrocytic schizogony where asynchronous nuclear divisions occur. In this study, we revisited the kinome of Plasmodium falciparum and identified three Aurora-related kinases, Pfark-1, -2, -3. Among these, Pfark-1 is highly conserved in malaria parasites and also appears to be conserved across Apicomplexa. By tagging the endogenous Pfark-1 gene with the green fluorescent protein (GFP) in live parasites, we show that the Pfark-1-GFP protein forms paired dots associated with only a subset of nuclei within individual schizonts. Immunofluorescence analysis using an anti-α-tubulin antibody strongly suggests a recruitment of Pfark-1 at duplicated spindle pole bodies at the entry of the M phase of the cell cycle. Unsuccessful attempts at disrupting the Pfark-1 gene with a knockout construct further indicate that Pfark-1 is required for parasite growth in red blood cells. Our study provides new insights into the cell cycle control of malaria parasites and reports the importance of Aurora kinases as potential targets for new antimalarials.
极光激酶构成了一组保守的丝氨酸/苏氨酸蛋白激酶家族,在真核细胞分裂中发挥着重要作用。迄今为止,在原生动物门顶复体纲中,极光同源物仍未被描述。在疟原虫中,极光激酶的特征可能有助于理解红细胞裂殖过程中的细胞周期控制,在这个过程中发生异步核分裂。在这项研究中,我们重新研究了疟原虫的激酶组,鉴定出三种与极光相关的激酶,Pfark-1、-2、-3。其中,Pfark-1 在疟原虫中高度保守,似乎在顶复体纲中也保守。通过在活寄生虫中用绿色荧光蛋白(GFP)标记内源性 Pfark-1 基因,我们表明 Pfark-1-GFP 蛋白形成与单个裂殖子内仅一部分核相关的成对斑点。使用抗α-微管蛋白抗体的免疫荧光分析强烈表明 Pfark-1 在细胞周期 M 期进入时被招募到复制的纺锤体极体。用敲除构建体破坏 Pfark-1 基因的不成功尝试进一步表明 Pfark-1 是寄生虫在红细胞中生长所必需的。我们的研究为疟原虫的细胞周期控制提供了新的见解,并报告了极光激酶作为新抗疟药物潜在靶点的重要性。