Comparative transcriptome analysis of Eimeria maxima (Apicomplexa: Eimeriidae) suggests DNA replication activities...

Area of Science:

• Veterinary Parasitology
• Molecular Biology
• Poultry Science

Background:

• Chicken coccidiosis, caused by Eimeria species, results in significant economic losses in the poultry industry.
• Vaccination with attenuated parasites is a key control strategy.
• Mechanisms underlying biological differences in attenuated Eimeria strains remain unclear.

Purpose of the Study:

• To generate and characterize a precocious line of Eimeria maxima.
• To investigate the molecular mechanisms of precocity using comparative transcriptome analysis.

Main Methods:

• Sequential selection over 22 generations to obtain an E. maxima precocious line.
• Comparative transcriptome analysis of the precocious line and its parent strain at three developmental stages using Illumina sequencing.

Main Results:

• The E. maxima precocious line displayed decreased pathogenicity, reduced fecundity, and a significantly shortened prepatent time (98 hours).
• Gene expression analysis revealed upregulated organelle genes during oocyst development and protein translation genes from sporulated oocyst to merozoite.
• Key differences in the merozoite stage included downregulated genes related to protein cleavage and DNA replication in the precocious line.

Conclusions:

• A novel E. maxima precocious line was successfully generated and characterized.
• Suppressed DNA replication in the merozoite stage of the precocious line may explain its reduced fecundity.
• Findings provide a foundation for understanding Eimeria precocity and early gametocytogenesis in apicomplexan parasites.