Activation of LEDGF gene by thermal- and oxidative-stresses

LEDGF promotes survival of many cell types against a wide range of environm ental stresses, and cells responding to those stresses expressed higher lev els of heat shock proteins (Hsps). LEDGF/p75 is a weak coactivator of gener al transcription. We speculated that a stress signal may activate expressio n of the LEDGF gene, resulting in elevated levels of LEDGF which may activa te expression of stress-related proteins to protect cells from stresses. Le ns epithelial cells (LECs) and cos7 cells were cultured under heat- or oxid ative-stress, After cells mere cultured for defined time, we quantified LED GF mRNA and LEDGF protein with RT-PCR, Northern blot, and protein blot anal ysis, Our results showed that higher levels of LEDGF were found in both cel l types under heat- and oxdative-stress than that in cells cultured at nons tress condition. Thus, one of the primary events in the stress-related prot ective events is the activation of LEDGF, a regulatory protein, (C) 2000 Ac ademic Press.