| |  |
| |
| | Figure 2. Schematic representation of the ERK4 protein structure. Kinase, catalytic kinase domain; C34 conserved region in ERK3 and ERK4; SEG, activation loop motif containing the regulatory phosphorylation residue Ser186. |
| |
| Description | Extracellular signal-regulated kinase 4 (ERK4) is an atypical member of the mitogen-activated protein (MAP) kinase family of serine/threonine kinases. The human ERK4 protein is made of 587 amino acids and contains a typical kinase domain located at the N-terminal extremity. Another region with homology to the MAP kinase ERK3 (C34 domain) has been identified after the kinase domain. The function of the C34 domain is unknown. |
| Expression | MAPK4 mRNA is expressed to the highest level in the brain. Other sites of expression include the heart, lung, kidney, intestine, pancreas, parathyroid gland, prostate, thymus, ovary, eye and ear. |
| Localisation | ERK4 localizes to the cytoplasm and nucleus of a variety of cultured cells. |
| Function | Little is known about the regulation and functions of ERK4. The only known substrate of ERK4 is the protein kinase MK5. |
| Homology | ERK4 display 73% amino acid identity with ERK3 in the kinase domain. ERK4 and ERK3 define a distinct subfamily of MAP kinases that is found exclusively in vertebrates. |
| Heterogeneous expression of four MAP kinase isoforms in human tissues. |
| Gonzalez FA, Raden DL, Rigby MR, Davis RJ. |
| FEBS Lett. 1992 Jun 15;304(2-3):170-8. |
| PMID 1319925 |
| |
| The protein kinase ERK3 is encoded by a single functional gene: genomic analysis of the ERK3 gene family. |
| Turgeon B, Lang BF, Meloche S. |
| Genomics. 2002 Dec;80(6):673-80. |
| PMID 12504858 |
| |
| Genome-wide aberrations in pancreatic adenocarcinoma. |
| Nowak NJ, Gaile D, Conroy JM, McQuaid D, Cowell J, Carter R, Goggins MG, Hruban RH, Maitra A. |
| Cancer Genet Cytogenet. 2005 Aug;161(1):36-50. |
| PMID 16080956 |
| |
| Regulation of MAPK-activated protein kinase 5 activity and subcellular localization by the atypical MAPK ERK4/MAPK4. |
| Aberg E, Perander M, Johansen B, Julien C, Meloche S, Keyse SM, Seternes OM. |
| J Biol Chem. 2006 Nov 17;281(46):35499-510. |
| PMID 16971392 |
| |
| Characterization of the atypical MAPK ERK4 and its activation of the MAPK-activated protein kinase MK5. |
| Kant S, Schumacher S, Singh MK, Kispert A, Kotlyarov A, Gaestel M. |
| J Biol Chem. 2006 Nov 17;281(46):35511-9. |
| PMID 16973613 |
| |
| Atypical mitogen-activated protein kinases: structure, regulation and functions. |
| Coulombe P, Meloche S. |
| Biochim Biophys Acta. 2007 Aug;1773(8):1376-87. (REVIEW) |
| PMID 17161475 |
| |
