Census, molecular characterization and developmental expression of Leucine-Rich-Repeat proteins in Plasmodium falciparum

The capacity of Leucine-Rich Repeat or LRR proteins to interact with many ligands enables them to contribute to important cellular functions ranging from the regulation of the cell cycle to protein trafficking and signal transduction. In Plasmodium falciparum, little is known about the expression of these LRR proteins. Here, we identified the PfLRR genes and determined their transcriptional expression during the intraerythrocytic parasite life cycle. Exhaustive analysis of the P. falciparum genome revealed 14 potential genes encoding LRR-containing proteins, designated from PfLRR1 to PfLRR14. Molecular cloning and sequencing of the corresponding cDNA indicated that all PfLRRs contain 4-10 LRR motifs. Real-time quantitative PCR revealed that most of genes are highly expressed in late intraerythrocytic stages, including late trophozoites and schizonts. The ability of P. falciparum to express LRR-containing proteins will enable further investigations into the parasite interactome and create opportunities for discovering candidate drug targets.