Organization
Division of Molecular Cell Signaling
Staff
Professor
YOSHIOKA, Katsuji
Abnormal activation of intracellular signaling pathways often leads to tumors. The goal of our project is to elucidate the functions of MAP kinase (MAPK) cascades in vivo, which are major intracellular signaling pathways, the functions of MAPK cascade scaffolds JSAP1 and JLP, and the molecular mechanisms of how the specificity of MAPK cascades is maintained.
Fig. 1 ■ Function of MAPK cascade in vivo, and Formation of Multikinase Complex by Scaffold Protein
Recent studies indicate that MAPK cascades, in which major components are MAPK, MAPK kinase (MAPKK), and MAPKK kinase (MAPKKK), play important roles in cell proliferation, differentiation, and apoptosis. Scaffold proteins could contribute to the specificity determination of MAPK cascades.
Fig. 2 ■ JLP ablation reduces ultraviolet B (UVB)-induced apoptosis in mice.
The ultraviolet B (UVB) component of sunlight can cause severe damage to skin cells and even induce skin cancer. We investigated the function of the scaffold protein JLP in UVB-induced apoptosis in the skin by analyzing Jlp-deficient mice. Our results suggest that JLP plays an important role in this apoptosis by modulating p38 MAPK signaling cascades.
