Serine/threonine-protein kinase that phosphorylates SFPQ/PSF, HNRNPA1 and EIF4E. May play a role in the response to environmental stress and cytokines. Appears to regulate translation by phosphorylating EIF4E, thus increasing the affinity of this protein for the 7-methylguanosine-containing mRNA cap. Required for mediating PP2A-inhibition-induced EIF4E phosphorylation. Triggers EIF4E shuttling from cytoplasm to nucleus. Enhances the formation of EIF4F complex in pachytene spermatocytes, thus promoting mRNA translation during spermatogenesis. Displays a high basal kinase activity. Acts as a mediator of the suppressive effects of IFNgamma on hematopoiesis. Negative regulator for signals that control generation of arsenic trioxide As(2)O(3)-dependent apoptosis and anti-leukemic responses. Involved in anti-apoptotic signaling in response to serum withdrawal. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Binds 1 zinc ion per monomer. Inhibited by CGP57380 and staurosporine. Interacts with ESR2 and EIF4E in the nucleus (By similarity). Monomer. Interacts with the C-terminal regions of EIF4G1 and EIF4G2; this interaction is promoted when MAPK pathways are repressed but repressed upon ERK proteins activation. Also binds to dephosphorylated MAPK3/ERK1 and MAPK1/ERK2. Interaction with phosphorylated MAPK3/ERK1 and MAPK1/ERK2 protects it from dephosphorylation and inactivation. Ubiquitously expressed in all tissues examined, with high levels in skeletal muscle and low levels in brain. Dual phosphorylation of Thr-244 and Thr-249 activates the kinase. Phosphorylation of Thr-379 activates the kinase. Phosphorylated upon arsenic trioxide As(2)O(3) treatment. Phosphorylated by MAPK1/ERK2, MAPK11 and MAPK14 (By similarity). Dephosphorylated by PP2A. Belongs to the protein kinase superfamily. CAMK Ser/Thr protein kinase family.