Atypical kinase involved in the biosynthesis of coenzyme Q, also named ubiquinone, an essential lipid-soluble electron transporter for aerobic cellular respiration. Its substrate specificity is unclear: does not show any protein kinase activity. Probably acts as a small molecule kinase, possibly a lipid kinase that phosphorylates a prenyl lipid in the ubiquinone biosynthesis pathway. Required for podocyte migration. Homodimer; homodimerizes via its transmembrane region. Interacts with the multi-subunit COQ enzyme complex. Adopts an atypical protein kinase-like fold: while it adopts a core fold similar to that of well-characterized protein kinase-like domains. The KxGQ motif completely occludes the typical substrate binding pocket. Nucleotide-binding opens the substrate binding pocket and flips the active site from inside the hydrophobic core into a catalytically competent, solvent-exposed posture. Morpholino knockdown of the protein causes nephrosis phenotype of periorbital edema and total body edema in 54% of embryos at 120 hpf. The glomerular structures are altered, with podocyte foot process effacement and disorganization, rarefaction of slit membranes, and disorganization of the glomerular basement membranes. Belongs to the protein kinase superfamily. ADCK protein kinase family.