Global profiling of protein S-palmitoylation in the second-generation merozoites of Eimeria tenella

Abstract

The intracellular protozoan Eimeria tenella is responsible for avian coccidiosis which is characterized by host intestinal damage and death. During developmental cycle, E. tenella undergoes versatile transitional stages such as oocyst, sporozoites, merozoites as well as gametocytes. These developmental transitions involved changes in cell shape and cell size requiring cytoskeletal remodeling and changes in membrane proteins, which may require transcriptional and translational regulations as well as post-translational modification of proteins. Palmitoylation is a post-translational modification (PTM) of protein that orchestrates protein targeting, folding, stability, regulated enzymatic activity and even epigenetic regulation of gene expression. Previous research revealed that protein palmitoylation play essential role in Toxoplasma gondii, Trypanosoma cruzi, Trichomonas vaginalis and several Plasmodium parasites. Until now, there is little information on the enzymes related to palmitoylation and role of protein palmitoylation in E. tenella. Therefore, a palmitome of the second-generation merozoite of E. tenella was investigated. We identified a total of 2569 palmitoyl-sites that were assigned to 2145 palmitoyl-peptides belonging to 1561 protein-groups that participated in biological processes including parasite morphology, motility and host cell invasion. In addition, RNA biosynthesis, protein biosynthesis, folding, proteasome-ubiquitin degradation and enzymes involved in PTMs, carbohydrate metabolism, glycan biosynthesis and mitochondrial respiratory chain as well as vesicle trafficking were identified. The study allowed us to decipher the broad influence of palmitoylation in E. tenella biology, and thus lay a solid foundation to interpret its roles in the pathobiology of E. tenella infection. Raw data are publicly available at iProX with the dataset identifier PXD045061.