Activation of the Sap-1a Transcription Factor by the c-Jun N-terminal Kinase (JNK) Mitogen-activated Protein Kinase

摘要: Ternary complex factors (TCFs) bind to the serum response element in c-fos promoter and mediate its activation by many extracellular stimuli. Some of these stimuli activate ERK subclass mitogen-activated protein kinases (MAPKs) that target TCF Sap-1a. We show Sap-1a is also phosphorylated stress-activated JNK MAPKs leading stimulation both E74-site-dependent transcription RK13 cells. Several JNK-1 phosphorylation sites were mapped within Sap-1a, mutation affected transactivation mediated JNK-1. The impact varied at different promoters was dependent on whether stimulated ERK-1 or Additionally, a comparison with another TCF, Elk-1, revealed proteins behaved differently Furthermore, inhibited p38MAPK cells, possibly competition for common upstream activator. Altogether, our data suggest plays an important role nuclear elicited cellular stress.