Abstract: Disclosed herein are two newly identified enzymes—mitogen-activated protein kinase-activated protein kinase-2, each comprising a sequence of nucleotides as set forth in SEQ ID NOs: 1 and 3. Each of the herein disclosed enzymes is a serine/threonine signal transduction kinase that is phosphorylated and activated by Erks and p38 MAPK in vitro. Also disclosed, inter alia, are cells containing the recombinant nucleic acid molecules; antisense constructs thereto; antibodies specific for each of the disclosed proteins; methods for using the novel nucleic acid molecules and their gene products including kits containing the same.