4h39

Structural highlights

Disease

[MK10_HUMAN] Defects in MAPK10 are a cause of epileptic encephalopathy Lennox-Gastaut type (EELG) [MIM:606369]. Epileptic encephalopathies of the Lennox-Gastaut group are childhood epileptic disorders characterized by severe psychomotor delay and seizures. Note=A chromosomal aberration involving MAPK10 has been found in a single patient. Translocation t(Y;4)(q11.2;q21) which causes MAPK10 truncation. [JIP1_HUMAN] Defects in MAPK8IP1 are a cause of non-insulin-dependent diabetes mellitus (NIDDM) [MIM:125853]. NIDDM is characterized by an autosomal dominant mode of inheritance, onset during adulthood and insulin resistance.^[1]

Function

[MK10_HUMAN] Serine/threonine-protein kinase involved in various processes such as neuronal proliferation, differentiation, migration and programmed cell death. Extracellular stimuli such as proinflammatory cytokines or physical stress stimulate the stress-activated protein kinase/c-Jun N-terminal kinase (SAP/JNK) signaling pathway. In this cascade, two dual specificity kinases MAP2K4/MKK4 and MAP2K7/MKK7 phosphorylate and activate MAPK10/JNK3. In turn, MAPK10/JNK3 phosphorylates a number of transcription factors, primarily components of AP-1 such as JUN and ATF2 and thus regulates AP-1 transcriptional activity. Plays regulatory roles in the signaling pathways during neuronal apoptosis. Phosphorylates the neuronal microtubule regulator STMN2. Acts in the regulation of the beta-amyloid precursor protein/APP signaling during neuronal differentiation by phosphorylating APP. Participates also in neurite growth in spiral ganglion neurons.^[2] [JIP1_HUMAN] The JNK-interacting protein (JIP) group of scaffold proteins selectively mediates JNK signaling by aggregating specific components of the MAPK cascade to form a functional JNK signaling module. Required for JNK activation in response to excitotoxic stress. Cytoplasmic MAPK8IP1 causes inhibition of JNK-regulated activity by retaining JNK in the cytoplasm and inhibiting JNK phosphorylation of c-Jun. May also participate in ApoER2-specific reelin signaling. Directly, or indirectly, regulates GLUT2 gene expression and beta-cell function. Appears to have a role in cell signaling in mature and developing nerve terminals. May function as a regulator of vesicle transport, through interactions with the JNK-signaling components and motor proteins (By similarity). Functions as an anti-apoptotic protein and whose level seems to influence the beta-cell death or survival response.

See Also

• Mitogen-activated protein kinase

References

1. ↑ Waeber G, Delplanque J, Bonny C, Mooser V, Steinmann M, Widmann C, Maillard A, Miklossy J, Dina C, Hani EH, Vionnet N, Nicod P, Boutin P, Froguel P. The gene MAPK8IP1, encoding islet-brain-1, is a candidate for type 2 diabetes. Nat Genet. 2000 Mar;24(3):291-5. PMID:10700186 doi:10.1038/73523
2. ↑ Neidhart S, Antonsson B, Gillieron C, Vilbois F, Grenningloh G, Arkinstall S. c-Jun N-terminal kinase-3 (JNK3)/stress-activated protein kinase-beta (SAPKbeta) binds and phosphorylates the neuronal microtubule regulator SCG10. FEBS Lett. 2001 Nov 16;508(2):259-64. PMID:11718727
3. ↑ Laughlin JD, Nwachukwu JC, Figuera-Losada M, Cherry L, Nettles KW, Lograsso PV. Structural Mechanisms of Allostery and Autoinhibition in JNK Family Kinases. Structure. 2012 Nov 6. pii: S0969-2126(12)00374-7. doi:, 10.1016/j.str.2012.09.021. PMID:23142346 doi:http://dx.doi.org/10.1016/j.str.2012.09.021