TUMOR-NECROSIS-FACTOR ALPHA-INDUCED E-SELECTIN EXPRESSION IS ACTIVATED BY THE NUCLEAR FACTOR-KAPPA-B AND C-JUN N-TERMINAL KINASE P38 MITOGEN-ACTIVATED PROTEIN-KINASE PATHWAYS/

E-selectin expression by endothelium is crucial for leukocyte recruitm ent during inflammatory responses. Transcriptional regulation of the E -selectin promoter by tumor necrosis factor alpha (TNF alpha) requires multiple nuclear factor-kappa B (NF-kappa B) binding sites and a cAMP -responsive element/activating transcription factor-like binding site designated positive domain II (PDII). Here we characterize the role of the stress-activated family of mitogen-activated protein (MAP) kinase s in induced expression of this adhesion molecule. By UV cross-linking and immunoprecipitation, we demonstrated that a heterodimer of transc ription factors ATF-2 and c-JUN is constitutively bound to the PDII si te. TNF alpha stimulation of endothelial cells induces transient phosp horylation of both ATF-2 and c-JUN and induces marked activation of th e c-JUN N-terminal kinase (JNK1) and p38 but not extracellular signal- regulated kinase (ERK1). JNK and p38 are constitutively present in the nucleus, and DNA-bound c-JUN and ATF-2 are stably contacted by JNK an d p38, respectively. MAP/ERK kinase kinase 1 (MEKK1), an upstream acti vator of MAP kinases, increases E-selectin promoter transcription and requires an intact PDII site for maximal induction. MEKK1 can also act ivate NF-kappa B -dependent gene expression. The effects of dominant i nterfering forms of the JNK/p38 signaling pathway demonstrate that act ivation of these kinases is critical for cytokine-induced E-selectin g ene expression. Thus, TNF alpha activates two signaling pathways, NF-k appa B and JNK/p38, which are both required for maximal expression of E-selectin.