Calcium-dependent protein kinase which acts as a sensor and effector of intracellular Ca(2+) levels probably in part downstream of cGMP-activated PKG kinase (By similarity). During the liver stage, involved in sporozoite motility and thus in sporozoite invasion of host hepatocytes, probably together with CDPK4 and CDPK5. In the mosquito midgut and during the last stage of male gamete exflagellation, may play a role in the rupture of the host erythrocyte membrane. In the mosquito midgut, required for the differentiation of the zygote into the ookinete by promoting the translational activation of a subset of repressed mRNAs; these mRNAs are kept repressed in the zygote by the DOZI- or CITH-containing mRNP complexes. Dispensable during the asexual blood stage (By similarity). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Activated by calcium. Upon calcium binding to the EF-hand domains, the C-terminus of the junction domain (J domain) undergoes a conformational change which results in the dissociation of the pseudo-substrate inhibitory motif from the catalytic domain. This, in turn may facilitate the autophosphorylation of the activation loop at Thr-230, which leads to the kinase activation. Monomer. Calcium and/or autophosphorylation does not affect membrane localization. The junction domain (J domain) is composed of 2 motifs that maintain the kinase inactive. The N-terminal autoinhibitory motif acts as a pseudosubstrate inhibiting the catalytic domain while the C-terminal motif binds the EF-hand domains. Myristoylated. Myristoylation and palmitoylation are required for the localization to the parasitophorous vacuole membrane. Palmitoylated. Palmitoylation increases in merozoites in response to low level of extracellular K(+) in the host blood. Myristoylation and palmitoylation are required for the localization to the parasitophorous vacuole membrane. Phosphorylation at Thr-230 may regulate CDPK1 kinase activity. Phosphorylation increases in response to an increase in intracellular Ca(2+) levels. Autophosphorylated in vitro. Autophosphorylation does not affect membrane localization in vitro. Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. CDPK subfamily.