Division of Molecular Parasitology, Proteo-science Center, Ehime University, 454 Shitsukawa, Toon, Ehime 791-0295, Japan.
Department of Parasitology and Tropical Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
Parasitol Int. 2024 Aug;101:102892. doi: 10.1016/j.parint.2024.102892. Epub 2024 Mar 31.
Reducing Plasmodium parasite transmission via the mosquito vector is a promising strategy for malaria control and elimination in endemic regions. In the mosquito midgut after the ingestion of an infected blood meal, malaria parasite gametes egress from erythrocytes and fertilize to develop into motile ookinetes that traverse midgut epithelial cells and transform into oocysts adjacent the basal lamina. Plasmodium ookinetes and young oocysts possess a unique organelle called the crystalloid; which has a honeycomb-like matrix structure and is indicated to be involved in sporozoite formation and maturation. In this study, we identified a novel crystalloid protein, PY17X_1113800, that is exclusively expressed in developing ookinetes. The protein possesses a signal peptide sequence, but lacks a transmembrane domain or GPI anchor signal sequence, as well as predicted adhesive domains which are characterisitic of many crystalloid proteins. The protein is highly conserved across the phylum Apicomplexa and within the greater clade Alveolata, such as Vitrella and the ciliates Paramecium and Tetrahymena, but is absent in cryptosporidia.
通过蚊虫媒介减少疟原虫寄生虫的传播，是在流行地区控制和消除疟疾的一个很有前途的策略。在蚊子的中肠中，被感染的血液被摄入后，疟原虫配子从红细胞中逸出并受精，发育成能运动的动合子，穿过中肠上皮细胞，并转化为靠近基底膜的卵囊。疟原虫动合子和早期卵囊具有一种独特的细胞器，称为晶体；它具有蜂窝状的基质结构，被认为参与子孢子的形成和成熟。在这项研究中，我们鉴定了一种新的晶体蛋白，PY17X_1113800，它只在发育中的动合子中表达。该蛋白具有信号肽序列，但缺乏跨膜结构域或 GPI 锚定信号序列，以及许多晶体蛋白所具有的预测的黏附结构域。该蛋白在整个顶复门和更广泛的类锥体门中高度保守，如玻璃质体和纤毛类的草履虫和四膜虫，但在隐孢子虫中不存在。
