Analysis of CDPK1 targets identifies a trafficking adaptor complex that regulates microneme exocytosis in <i>Toxoplasma</i>.

ABSTRACT: Apicomplexan parasites use Ca²⁺-regulated exocytosis to secrete essential virulence factors from specialized organelles called micronemes. Ca²⁺-dependent protein kinases (CDPKs) are required for microneme exocytosis; however, the molecular events that regulate trafficking and fusion of micronemes with the plasma membrane remain unresolved. Here, we combine sub-minute resolution phosphoproteomics and bio-orthogonal labeling of kinase substrates in Toxoplasma gondii to identify 163 proteins phosphorylated in a CDPK1-dependent manner. In addition to known regulators of secretion, we identify uncharacterized targets with predicted functions across signaling, gene expression, trafficking, metabolism, and ion homeostasis. One of the CDPK1 targets is a putative HOOK a

SUBMITTER: Chan AW 

PROVIDER: S-EPMC9882037 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature