A comprehensive proteome and the first phosphoproteome reveal extensive phosphorylation of carbohydrate metabolism in Cryptosporidium parvum sporozoites

作者：DongQiang Wang, Meng Li, Chenchen Wang, Haitao Li, Jigang Yin, Guan Zhu · 发表于：bioRxiv (Cold Spring Harbor Laboratory) · 年份：2026 · DOI：10.64898/2026.01.20.700507 · 研究领域：Parasitic Infections and Diagnostics、Parasites and Host Interactions、Amoebic Infections and Treatments

Abstract Cryptosporidium parvum is an obligate intracellular apicomplexan parasite and a major cause of diarrheal disease in humans and animals worldwide. Despite its public health importance, the molecular regulation of parasite metabolism, particularly at the post-translational level, remains poorly understood. Here, we present a comprehensive proteomic analysis and the first phosphoproteomic profile of excysted C. parvum sporozoites, the invasive stage responsible for host cell entry. Using data-independent acquisition–based mass spectrometry, we identified 2,272 proteins, representing approximately 58% of the predicted parasite proteome, and 8,994 phosphorylation sites across 833 phosphoproteins. Comparative analyses revealed weak correlations between transcript and protein abundance, underscoring extensive post- transcriptional regulation in sporozoites. Functional enrichment analyses showed that proteins involved in carbohydrate metabolism, particularly glycolysis, are highly abundant in the sporozoite proteome. In contrast, phosphoproteomic data revealed that many core glycolytic enzymes exhibit relatively low phosphorylation propensity, suggesting limited reliance on phosphorylation-based regulation for basal energy metabolism at this stage. To integrate proteomic and phosphoproteomic measurements acquired independently, we developed a relative phosphorylation index (RPI) that enables comparative assessment of phosphorylation propensity across proteins. Application of...