Infectivity-associated changes in the transcriptional repertoire of the malaria parasite sporozoite stage.
Injection of Plasmodium salivary gland sporozoites into the vertebrate host by Anopheles mosquitoes initiates malaria infection. Sporozoites develop within oocysts in the mosquito midgut and then enter and mature in the salivary glands. Although morphologically similar, oocyst sporozoites and salivary gland sporozoites differ strikingly in their infectivity to the mammalian host, ability to elicit protective immune responses, and cell motility. Here, we show that differential gene expression coincides with these dramatic phenotypic differences. Using suppression subtractive cDNA hybridization we identified highly up-regulated mRNAs transcribed from 30 distinct genes in salivary gland sporozoites. Of those genes, 29 are not significantly expressed in the parasite's blood stages. The most frequently recovered transcript encodes a protein kinase. Developmental up-regulation of specific mRNAs in the infectious transmission stage of Plasmodium indicates that their translation products may have unique roles in hepatocyte infection and/or development of liver stages.
Matuschewski
Kai
K
Michael Heidelberger Division, Department of Pathology, New York University School of Medicine, New York 10016, USA. Kai_Matuschewski@med.uni-heidelberg.de
Ross
Jessica
J
Brown
Stuart M
SM
Kaiser
Karine
K
Nussenzweig
Victor
V
Kappe
Stefan H I
SH
D000818:Animals; D018932:Chemokine CCL2 / Q000235:genetics; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D010961:Plasmodium / Q000235:genetics* / Q000472:pathogenicity; D015800:Protozoan Proteins / Q000235:genetics; D034101:Sporozoites / Q000235:genetics*; D014158:Transcription, Genetic
D018932:Chemokine CCL2; D015800:Protozoan Proteins; C041595:circumsporozoite protein, Protozoan; C069428:thrombospondin-related adhesive protein, protozoan