Investigation of c-Jun N-terminal Kinase 2 Regulation
JNK2). This protein is unique in that it can autophosphorylate, or phosphorylate itself. It was found that these proteins tend to form aggregates of four, or tetramers, when inactive and remain as single units, or monomers, when active. In glioblastoma and lung carcinoma cells, JNK2s are reported to be constitutively, or always, active. This study aimed to investigate a selection of JNK2 mutations determine which of these mutations can alter JNK2 activity and oligomerization state. Results from size-exclusion chromatography and light scattering analysis (SEC-LS) suggested that while the wild type JNK2 exists as a mixture of monomers and tetramers, the activation loop chimera mutant (C177G/N179S) exists only as monomers. Additionally, phosphorylation assay analysis showed increased autophosphorylation activity of the activation loop chimera mutant compared to the wild type. These results suggest that the activation loop may be involved in the mechanism of JNK2 regulation. Elucidation of MAPK regulation mechanisms may allow more effective cancer therapy screening and increase overall understanding of tumor growth mechanisms.