1. Distinct malaria parasite sporozoites reveal transcriptional changes that cause differential tissue infection competence in the mosquito vector and mammalian host.
- Author
-
Mikolajczak SA, Silva-Rivera H, Peng X, Tarun AS, Camargo N, Jacobs-Lorena V, Daly TM, Bergman LW, de la Vega P, Williams J, Aly AS, and Kappe SH
- Subjects
- Animals, Gene Expression Profiling, Gene Expression Regulation, Gene Targeting, Genes, Protozoan, Hemolymph cytology, Hemolymph metabolism, Host-Parasite Interactions, Injections, Intravenous, Mice, Oocysts cytology, Oocysts metabolism, Parasites cytology, Parasites genetics, Parasites pathogenicity, Plasmodium falciparum genetics, Plasmodium yoelii genetics, Protein Transport, Protozoan Proteins genetics, Protozoan Proteins metabolism, Salivary Glands parasitology, Sporozoites cytology, Anopheles parasitology, Insect Vectors parasitology, Malaria genetics, Malaria parasitology, Mammals parasitology, Sporozoites metabolism, Transcription, Genetic
- Abstract
The malaria parasite sporozoite transmission stage develops and differentiates within parasite oocysts on the Anopheles mosquito midgut. Successful inoculation of the parasite into a mammalian host is critically dependent on the sporozoite's ability to first infect the mosquito salivary glands. Remarkable changes in tissue infection competence are observed as the sporozoites transit from the midgut oocysts to the salivary glands. Our microarray analysis shows that compared to oocyst sporozoites, salivary gland sporozoites upregulate expression of at least 124 unique genes. Conversely, oocyst sporozoites show upregulation of at least 47 genes (upregulated in oocyst sporozoites [UOS genes]) before they infect the salivary glands. Targeted gene deletion of UOS3, encoding a putative transmembrane protein with a thrombospondin repeat that localizes to the sporozoite secretory organelles, rendered oocyst sporozoites unable to infect the mosquito salivary glands but maintained the parasites' liver infection competence. This phenotype demonstrates the significance of differential UOS expression. Thus, the UIS-UOS gene classification provides a framework to elucidate the infectivity and transmission success of Plasmodium sporozoites on a whole-genome scale. Genes identified herein might represent targets for vector-based transmission blocking strategies (UOS genes), as well as strategies that prevent mammalian host infection (UIS genes).
- Published
- 2008
- Full Text
- View/download PDF