Essential for release from glucose repression. It interacts and has functional relationship to the regulatory protein SNF4. Could phosphorylate CAT8 (By similarity). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Belongs to the protein kinase superfamily. CAMK Ser/Thr protein kinase family. SNF1 subfamily.