Expression and co-localization of proteins of Pfs38 complex on Plasmodium merozoites. Co-localization studies were performed by immunofluorescence assays. Merozoites were labelled with (a) mouse anti-Pfs38 and rabbit anti-GLURP or with (b) mouse anti-Pfs38 and rabbit anti-Pfs41 antibodies or with (c) mouse anti-Pfs38 and rabbit anti-Pfs12 antibodies or with (d) mouse anti-Pfs38 and rabbit anti-PfsMSP165 antibodies. Partial co-localization was observed between Pfs38 and other proteins of 6-Cys complex with co-localization coefficient of 0.75, 0.61, 0.82, and 0.83 for a–d, respectively. Td represent bright field images. Pfs38 partially co-localized with GLURP, Pfs41, Pfs12, and MSP-1, advocating the co-existence of proteins of 6-Cys protein complex on the merozoite surface (Fig. 3a–d). These results were corroborated by cosedimentation analysis of parasite-derived polypeptides. Western blotting and LC–MS/MS analysis of the glycerol gradient fractions revealed the presence of Pfs38, Pfs41, Pfs12, GLURP, MSP-1, and SERA5 in a single fraction, suggesting that these proteins exist in a complex on the parasite.

Paul G, Deshmukh A, Kaur I, Rathore S, Dabral S, Panda A, Singh SK, Mohmmed A, Theisen M, Malhotra P. A novel Pfs38 protein complex on the surface of Plasmodium falciparum blood-stage merozoites. Malar J. 2017 16(1):79