Cellular function of p70S6K: A role in regulating cell motility

Abstract

The 70 kDa ribosomal S6 kinase (p70(S6K)) is activated by numerous mitogens, growth factors and hormones. Activation of p70(S6K) occurs through phosphorylation at a number of sites and the primary target of the activated kinase is the 40S ribosomal protein S6, a major component of the machinery involved in protein synthesis in mammalian cells. In addition to its involvement in regulating translation, p70(S6K) activation has been implicated in cell cycle control and neuronal cell differentiation. Recent data obtained in this laboratory suggests that p70(S6K) may also function in regulating cell motility, a cellular response that is important in tumour metastases, the immune response and tissue repair. The present paper reviews the regulation and cellular function of p70(S6K) and proposes a novel function of p70(S6K) in regulating cell motility.