Activation of the human p27(Kip1) promoter by IFN alpha 2b

p27(Kip1) is one of the key regulatory proteins in cell cycle through inhib ition of pRB phosphorylation by suppression of the activity of several cycl in/Cdk complexes. The expression of p27(Kip1) has been shown to be controll ed by a posttranslational mechanism, although vitamin D-3 and neuronal diff erentiation can also induce its mRNA. Recently, the p27(Kip1) promoter was isolated and sequenced from a human leukocyte genomic library. In this repo rt, we demonstrate that IFN alpha 2b, activates the human p27(Kip1) promote r-driven luciferase reporter gene in transient expression assays in H82 cel ls, This induction might involve two IRF 1-like binding sites present in th e p27(Kip1) promoter. To our knowledge this is the first report on the dire ct activation of the human p27(Kip1) promoter by IFN alpha 2b. (C) 2000 Aca demic Press.