A chemical genetic approach reveals CDPK4 activity is required to initiate the first round of DNA replication, assemble the first mitotic spindle and initiate axoneme motility. Immunofluorescence assays showing the effect of 1294 at different time points after activation. Addition of 1 mM 1294 at the time of activation prevents the formation of mitotic spindles as observed 1 min after activation in presence of DMSO. Addition of 1294 at 30 s or at 9 min post-activation does not inhibit axoneme formation but blocks initiation of axoneme motility and condensation of chromatin. Absence of 1294 treatment leads to the exflagellation of male gametes 10 min after activation. Scale bars = 1 mm.
Fang H, Klages N, Baechler B, Hillner E, Yu L, Pardo M, Choudhary J, Brochet M. Multiple short windows of calcium-dependent protein kinase 4 activity coordinate distinct cell cycle events during Plasmodium gametogenesis. Elife. 2017 May 8;6. pii: e26524.