Flippase activator that phosphorylates DNF1 and DNF2 and which is involved in the generation of phospholipid asymmetry in membranes by the inward translocation of phospholipids and in the retrieval pathway from early endosomes to the trans-Golgi network (TGN). Phosphorylates also the N-terminal half of YPK1. Involved in pheromone-response. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Down-regulated by YKP1 phosphorylation. This effect is counteracted in the presence of mannosyl-inositolphosphorylceramide (MIPC). The N-terminal non-catalytic domain is phosphorylated by YPK1. Present with 752 molecules/cell in log phase SD medium. Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. KIN82 subfamily.