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Plasmodium falciparum Cysteine Rich Secretory Protein uniquely localizes to one end of male gametes.

ABSTRACT: Fertilization is a central event during the life cycle of most eukaryotic organisms and involves gamete recognition and fusion, ultimately resulting in zygote formation. Gamete fertilization in the malaria-causing Plasmodium parasites occurs inside the mosquito midgut and represents a major bottleneck in the life cycle. Cysteine Rich Secretory Proteins (CRISPs) are key molecules involved in fertilization in vertebrates and the presence of a CRISP ortholog in human malaria infective Plasmodium falciparum suggested a possible role in fertilization. Strikingly, P. falciparum CRISP exhibited a unique terminal localization in the male microgamete. Parasites with a CRISP gene deletion (P. falciparum crisp^-) proliferated asexually similar to wildtype NF54 parasites and differentiated into gametocytes. Further analysis showed that Plasmodium falciparum crisp^- gametocytes underwent exflagellation to form male gametes and no apparent defect in transmission to the mosquito vector was observed. These data show that P. falciparum CRISP is a marker for the apical end of the microgamete and that it might only have an ancillary or redundant function in the male sexual stages.

SUBMITTER: Kumar S

PROVIDER: S-EPMC8904303 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Plasmodium falciparum Cysteine Rich Secretory Protein uniquely localizes to one end of male gametes.

Kumar Sudhir S Leeb Amanda S AS Vaughan Ashley M AM Kappe Stefan H I SHI

Molecular and biochemical parasitology 20220105

Fertilization is a central event during the life cycle of most eukaryotic organisms and involves gamete recognition and fusion, ultimately resulting in zygote formation. Gamete fertilization in the malaria-causing Plasmodium parasites occurs inside the mosquito midgut and represents a major bottleneck in the life cycle. Cysteine Rich Secretory Proteins (CRISPs) are key molecules involved in fertilization in vertebrates and the presence of a CRISP ortholog in human malaria infective Plasmodium fa ...[more]

PMID: 34998927

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Plasmodium falciparum Cysteine Rich Secretory Protein uniquely localizes to one end of male gametes.

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Plasmodium falciparum Cysteine Rich Secretory Protein uniquely localizes to one end of male gametes.

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