Genetic crosses and complementation reveal essential functions for the Plasmodium stage-specific actin2 in sporogonic development.

摘要: Malaria parasites have two actin isoforms, ubiquitous actin1 and specialized actin2. Actin2 is essential for late male gametogenesis, prior to egress from the host erythrocyte. Here, we examined whether actins fulfil overlapping functions in Plasmodium berghei. Replacement of actin2 with resulted partial complementation defects gametogenesis and, thus, viable ookinetes were formed, able invade midgut epithelium develop into oocysts. However, these remained small their DNA was undetectable at day 8 after infection. As a consequence sporogony did not occur, resulting complete block parasite transmission. Furthermore, show that expression tightly controlled female stages. The transcript translationally repressed gametocytes, but translated gametes. protein persists until mature ookinetes; this strictly dependent on maternally derived expression. Genetic crosses revealed an early stage ookinete formation lacking are unable undergo mosquito midgut. Our results provide insights role development suggest isoforms distinct biological functions.