CNA

In Toxoplasma gondii, CNA is the catalytic subunit of calcineurin, a calcium-regulated phosphatase complex that critically regulates recognition of and stable attachment to host cells by extracellular parasites prior to intracellular entry, such that calcineurin function is required for host cell engagement (PMID:26118996). Beyond this role in host cell attachment established by loss-of-function studies, no further mechanistic detail about CNA has been characterized in the available corpus.

1. 2015 Medium

   It was unknown how apicomplexan parasites stabilize their initial engagement with host cells; loss-of-function of the calcineurin complex established that this calcium-regulated phosphatase is required to stabilize extracellular parasite attachment before invasion.

   Evidence Reverse-genetic and chemical-genetic loss-of-function with host cell attachment/invasion phenotype readout in T. gondii and P. falciparum

   PMID:26118996

   Open questions at the time

   • No substrates of the CNA phosphatase identified
   • The specific contribution of the CNA catalytic subunit versus the whole calcineurin complex is not resolved
   • Mechanism linking calcium signaling to attachment stabilization is not defined