The Binding of Plasmodium falciparum Adhesins and Erythrocyte Invasion Proteins to Aldolase Is Enhanced by Phosphorylation.
The Binding of Plasmodium falciparum Adhesins and Erythrocyte Invasion Proteins to Aldolase Is Enhanced by Phosphorylation.
复制标题
恶性疟原虫粘附素和红细胞侵袭蛋白与醛糖酶的结合通过磷酸化增强。
DOI：
10.1371/journal.pone.0161850
复制
发表时间：
2016
期刊：
影响因子：
3.7
通讯作者：
Holder AA
中科院分区：
文献类型：
--
作者：
Diaz SA;Martin SR;Howell SA;Grainger M;Moon RW;Green JL;Holder AA
醛缩酶是一种偶联肌动球蛋白运动蛋白和细胞表面粘附素的蛋白，参与人类恶性疟原虫的运动和宿主细胞入侵。它结合到血小板反应蛋白相关匿名蛋白（TRAP）家族的1型膜蛋白的细胞质结构域（CTD）。其他1型膜蛋白位于裂殖子的顶端细胞器中，包括顶端膜抗原1 （AMA1）和红细胞结合配体（EBL）和网织红细胞结合同源（RH）蛋白家族的成员，它们与宿主细胞的结合和入侵有关。使用直接结合方法，我们证实了TRAP和merozoite TRAP （MTRAP）结合醛缩酶，并表明这种相互作用不仅仅是由c端6个氨基酸残基介导的。MTRAP CTD中单个氨基酸的取代使其与醛缩酶的结合失效。AMA1的CTDs以及EBL和RH蛋白家族成员也与醛缩酶结合。MTRAP与AMA1和RH4竞争结合醛缩酶，表明结合位点重叠。MTRAP CTD在体外被钙依赖性激酶1 （CDPK1）和蛋白激酶A磷酸化，这种修饰使其与醛缩酶的结合亲和力提高了10倍。在某些情况下，EBL和RH蛋白家族成员的CTD磷酸化也增加了它们对醛缩酶的亲和力。为了检测在无性血期寄生虫中表达的MTRAP是否被磷酸化，用GFP标记，纯化和分析，但未检测到磷酸化。我们认为CTD与醛缩酶的结合可能受到磷酸化的动态调节，不同的CTD之间可能存在醛缩酶结合的竞争。除了它们的宿主配体特异性外，粘附素和细胞入侵蛋白对醛缩酶的亲和力可能决定了替代入侵途径的使用和效率。
Aldolase has been implicated as a protein coupling the actomyosin motor and cell surface adhesins involved in motility and host cell invasion in the human malaria parasite Plasmodium falciparum. It binds to the cytoplasmic domain (CTD) of type 1 membrane proteins of the thrombospondin-related anonymous protein (TRAP) family. Other type 1 membrane proteins located in the apical organelles of merozoites, the form of the parasite that invades red blood cells, including apical membrane antigen 1 (AMA1) and members of the erythrocyte binding ligand (EBL) and reticulocyte binding homologue (RH) protein families have been implicated in host cell binding and invasion. Using a direct binding method we confirm that TRAP and merozoite TRAP (MTRAP) bind aldolase and show that the interaction is mediated by more than just the C-terminal six amino acid residues identified previously. Single amino acid substitutions in the MTRAP CTD abolished binding to aldolase. The CTDs of AMA1 and members of the EBL and RH protein families also bound to aldolase. MTRAP competed with AMA1 and RH4 for binding to aldolase, indicating overlapping binding sites. MTRAP CTD was phosphorylated in vitro by both calcium dependent kinase 1 (CDPK1) and protein kinase A, and this modification increased the affinity of binding to aldolase by ten-fold. Phosphorylation of the CTD of members of the EBL and RH protein families also increased their affinity for aldolase in some cases. To examine whether or not MTRAP expressed in asexual blood stage parasites is phosphorylated, it was tagged with GFP, purified and analysed, however no phosphorylation was detected. We propose that CTD binding to aldolase may be dynamically modulated by phosphorylation, and there may be competition for aldolase binding between different CTDs. The use and efficiency of alternate invasion pathways may be determined by the affinity of adhesins and cell invasion proteins for aldolase, in addition to their host ligand specificity.
登录
查看更多内容
影响因子：
1.5
作者：
Diaz SA;Martin SR;Grainger M;Howell SA;Green JL;Holder AA
通讯作者：
Holder AA
影响因子：
48
作者：
Andenmatten, Nicole;Egarter, Saskia;Jackson, Allison J;Jullien, Nicolas;Herman, Jean-Paul;Meissner, Markus
通讯作者：
Meissner, Markus
影响因子：
3.7
作者：
Egarter, Saskia;Andenmatten, Nicole;Meissner, Markus
通讯作者：
Meissner, Markus
影响因子：
4.8
作者：
Baum, J;Richard, D;Cowman, AF
通讯作者：
Cowman, AF
影响因子：
7.8
作者：
Gilberger, TW;Thompson, JK;Cowman, AF
通讯作者：
Cowman, AF