Plasmodium SIAP-1. (A) Schematic diagram of the primary structures of the apicomplexan SIAP-1 proteins. The primary structure of P. berghei SIAP-1 (PB000251.01.0; reannotated) and the orthologs of P. yoelii (PY00455), P. falciparum (PFD0425w), Plasmodium vivax (Pv000815), Babesia bovis (XP_001609197), and Theileria parva (XP_765499) are indicated with white boxes. The predicted cleavable signal peptide is represented in gray. Amino acid sequence identities are indicated as percentages of identical residues compared to the P. berghei sequence. (B) Quantitative RT-PCR analysis of P. berghei SIAP-1 gene expression in midgut oocysts (day 12 postinfection of mosquitoes), salivary gland sporozoites (day 18 postinfection of mosquitoes), early liver stages (6 h postinfection of HepG2 cells) and mixed blood stages. Relative gene expression was normalized to GFP expression level and is shown as the mean (± standard deviation) of the results from two independent experiments.