May be involved in cortical F-actin organization and resistance to osmotic stress. Activated upon cell detachment, in vitro. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Interacts with F-actin. Associated with the cytoskeletal cortex in response to chemoattractant stimulation. Colocalizes with F-actin in F-actin-enriched structures, including membrane ruffles and pseudopodia during chemotaxis. There are 2 transcripts. The smaller transcript is high in vegetative cells and during early development and rapidly decreases after 12 hours, the time of tipped aggregate formation. A larger transcript occurs at 8 hours of development, remains high through the 12 hours time point, and then decreases, like the smaller transcript. Autophosphorylated. Belongs to the protein kinase superfamily. TKL Ser/Thr protein kinase family. The gene for this protein is duplicated in strains AX3 and AX4. These strains contain a duplication of a segment of 750 kb of chromosome 2 compared to the corresponding sequence in strain AX2.