The aromatic amino acid hydroxylase genes AAH1 and AAH2 in Toxoplasma gondii contribute to transmission in the cat

PLoS Pathogens

Zi T. Wang¹  L. David Sibley¹  Shiv K. Verma²  Jitender P. Dubey² 

[1] Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America;United States Department of Agriculture, Agricultural Research Service, Beltsville Agricultural Research Center, Animal Parasitic Diseases Laboratory, Beltsville, Maryland, United States of America

关键词: Oocysts;    Parasitic intestinal diseases;    Cats;    Toxoplasma gondii;    Parasitic diseases;    Gastrointestinal tract;    Cloning;    Dopamine;   

DOI  :  10.1371/journal.ppat.1006272

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

The Toxoplasma gondii genome contains two aromatic amino acid hydroxylase genes, AAH1 and AAH2 encode proteins that produce L-DOPA, which can serve as a precursor of catecholamine neurotransmitters. It has been suggested that this pathway elevates host dopamine levels thus making infected rodents less fearful of their definitive Felidae hosts. However, L-DOPA is also a structural precursor of melanins, secondary quinones, and dityrosine protein crosslinks, which are produced by many species. For example, dityrosine crosslinks are abundant in the oocyst walls of Eimeria and T. gondii, although their structural role has not been demonstrated, Here, we investigated the biology of AAH knockout parasites in the sexual reproductive cycle within cats. We found that ablation of the AAH genes resulted in reduced infection in the cat, lower oocyst yields, and decreased rates of sporulation. Our findings suggest that the AAH genes play a predominant role during infection in the gut of the definitive feline host.

【 授权许可】

CC BY