Overview:

HSP27 is a member of heat shock proteins (HSPs) which are synthesized in cells in response to heat shock and other metabolic stresses and provide a transient state of thermotolerance. HSP27 plays a major role in the increased thermal resistance acquired by cells after exposure to HSP inducers (1). The level of HSP27 phosphorylation is significantly elevated after exposure of cells to heat shock, sodium arsenite, IL-1 and TNF-α. MAPKAPK2 and MAPKAPK3 are both activated by these conditions and can phosphorylate HSP27 on serine residues (2).

References:

1. Landry, J. et al: Heat shock resistance conferred by expression of the human HSP27 gene in rodent cells. J Cell Biol. 1989 Jul;109(1):7-15.

2. Clifton, A D. et al: A comparison of the substrate specificity of MAPKAP kinase-2 and MAPKAP kinase-3 and their activation by cytokines and cellular stress. FEBS Lett. 1996 Sep 2;392(3):209-14.