The central core of each mitogen-activated protein kinase (MAPK) pathway is a conserved cascade of 3 protein kinases: an activated MAPK kinase kinase (MAPKKK) phosphorylates and activates a specific MAPK kinase (MAPKK), which then activates a specific MAPK. While the ERK MAPKs are activated by mitogenic stimulation, the CSBP2 and JNK MAPKs are activated by environmental stresses such as osmotic shock, UV irradiation, wound stress, and inflammatory factors. This gene encodes a MAPKKK, the MEKK4 protein, also called MTK1. This protein contains a protein kinase catalytic domain at the C terminus. The N-terminal nonkinase domain may contain a regulatory domain. Expression of MEKK4 in mammalian cells activated the CSBP2 and JNK MAPK pathways, but not the ERK pathway. In vitro kinase studies indicated that recombinant MEKK4 can specifically phosphorylate and activate PRKMK6 and SERK1, MAPKKs that activate CSBP2 and JNK, respectively but cannot phosphorylate PRKMK1, an MAPKK that activates ERKs. MEKK4 is a major mediator of environmental stresses that activate the CSBP2 MAPK pathway, and a minor mediator of the JNK pathway. Several alternatively spliced transcripts encoding distinct isoforms have been described. [provided by RefSeq, May 2014]
Overall distribution
Tissue specific distribution
Overall distribution
Tissue specific distribution
Gscore (Amp):
0.00
Gscore (Del):
0.97 (Driver)
Recurrently deleted in 4 cancer type(s)
Overall distribution
Tissue specific distribution
Mscore:
0.02
Recurrently mutated in 1 cancer type(s)
Overall
Tissue specific
Total fusion occurrence:
5
Fusions detected in 4 cancer type(s)
Overall
Tissue specific
Functional class:
Kinase (protein kinase)
JensenLab PubMed score:
31.83 (Percentile rank: 54.96%)
PubTator score:
49.36 (Percentile rank: 67.60%)
Target development/druggability level:
TbioThese targets do not have known drug or small molecule activities that satisfy the activity thresholds detailed below AND satisfy one or more of the following criteria: 1) target is above the cutoff criteria for Tdark; 2) target is annotated with a Gene Ontology Molecular Function or Biological Process leaf term(s) with an Experimental Evidence code.
Tractability (small molecule):
Discovery PrecedenceTargets with ligands; Targets with crystal structures with ligands