Serine/threonine-protein kinase involved in energy homeostasis and protein translation. Phosphorylates EEF1A1, GYS1, PDX1 and RPS6. Probably plays a role under changing environmental conditions (oxygen, glucose, nutrition), rather than under standard conditions. Acts as a sensor involved in energy homeostasis: regulates glycogen synthase synthesis by mediating phosphorylation of GYS1, leading to GYS1 inactivation. May be involved in glucose-stimulated insulin production in pancreas and regulation of glucagon secretion by glucose in alpha cells; however such data require additional evidences. May play a role in regulation of protein translation by phosphorylating EEF1A1, leading to increase translation efficiency. May also participate to respiratory regulation. Ubiquitously expressed, with slightly higher expression in brain, prostate and testis. Reduced expression was found in placenta. Present in germ cells of testis and in the midpiece of sperm tails. Protein kinase activity is inhibited by the first PAS domain: binding of an unidentified ligand desinhibits the protein kinase activity. May be activated by autophosphorylation on Thr-1161 and Thr-1165 (PubMed:11459942). The activating role of autophosphorylation at Thr-1161 is unclear: according to a report, autophosphorylation at Thr-1161 does not play a major role in activation (PubMed:20943661). Autophosphorylation is enhanced upon phosphatidylinositol monophosphate (phosphatidylinositol 4-phosphate) binding and inhibited upon phosphatidylinositol bi- and tri-phosphate binding. In contrast, phosphorylation of target proteins is inhibited upon all phosphatidylinositol-binding (phosphatidylinositol mono- bi- and tri-phosphate). Belongs to the protein kinase superfamily. CAMK Ser/Thr protein kinase family. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Protein type: EC 188.8.131.52; Protein kinase, Ser/Thr (non-receptor); Protein kinase, CAMK; Kinase, protein; CAMK group; CAMKL family; PASK subfamily
Molecular Function: protein serine/threonine kinase activity; protein binding; signal transducer activity; phosphoinositide binding; ATP binding
Biological Process: regulation of respiratory gaseous exchange; positive regulation of translation; protein amino acid autophosphorylation; signal transduction; protein amino acid phosphorylation; negative regulation of glycogen biosynthetic process
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.