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. {ECO:0000269|PubMed:11463832, ECO:0000269|PubMed:15350534, ECO:0000269|PubMed:9155018, ECO:0000269|PubMed:9878069}. This is the function of MKNK1 (MAPK interacting serine/threonine kinase 1, ENSG00000079277).