Rajapandi Thavamani
Department of Natural Sciences, Science and Technology Center, Coppin State University, Room # 204, 2500 West North Avenue, Baltimore, MD 21216-3698 USA.
J Parasit Dis. 2020 Jun;44(2):467-471. doi: 10.1007/s12639-020-01209-5. Epub 2020 Mar 13.
Apicomplexans are a group of parasitic protozoans, including and species, which harbor a specialized organelle called an apicoplast. Of the 145-apicomplexan lineage-specific proteins identified in , 30 are surface proteins. In , a heteromeric complex of three related apicomplexan lineage-specific membrane proteins containing 6 transmembrane domains (m6t) have been identified. These proteins are Pfm6t α, Pfm6t β, and Pfm6t γ and these proteins are localized on merozoite as an inner membrane complex (Rayavara et al. in Mol Biochem Parasitol 167(2):135-143, 2009). In , homologs of these proteins are identified and are Cpm6t α, Cpm6t β, and Cpm6t γ. Mass spectrometric analysis of (Iowa II) protein extracts of oocyst, sporozoite and soluble and insoluble fractions of cytoplasm identified the presence of Cpm6t α, Cpm6t β, and Cpm6t γ specific peptides in these fractions. The expression of Cpm6t α, Cpm6t β, and Cpm6t γ proteins on various developmental stages of suggests that this novel group of apicomplexan lineage-specific proteins in Cryptosporidium may be involved in multiple cellular processes apart from the invasion into host epithelial cells as suggested for merozoites onto host erythrocytes.
顶复门原虫是一类寄生原生动物，包括疟原虫和隐孢子虫等物种，它们含有一种称为顶质体的特殊细胞器。在已鉴定出的145种顶复门谱系特异性蛋白中，有30种是表面蛋白。在疟原虫中，已鉴定出一种由三种相关的顶复门谱系特异性膜蛋白组成的异源复合物，这些蛋白含有6个跨膜结构域（m6t）。这些蛋白分别是Pfm6tα、Pfm6tβ和Pfm6tγ，它们定位于裂殖子的内膜复合物上（Rayavara等人，《分子生物化学寄生虫学》，2009年，第167卷第2期，第135 - 143页）。在隐孢子虫中，鉴定出了这些蛋白的同源物，即Cpm6tα、Cpm6tβ和Cpm6tγ。对卵囊、子孢子以及细胞质可溶和不可溶部分（爱荷华II型）的蛋白质提取物进行质谱分析，发现在这些部分中存在Cpm6tα、Cpm6tβ和Cpm6tγ特异性肽段。Cpm6tα、Cpm6tβ和Cpm6tγ蛋白在隐孢子虫不同发育阶段的表达表明，隐孢子虫中这一组新的顶复门谱系特异性蛋白可能除了参与如疟原虫裂殖子侵入宿主红细胞那样侵入宿主上皮细胞外，还参与多种细胞过程。
