| Product Detail | The human protooncogene JUN is the putative transforming gene of avian sarcoma virus 17, and it encodes a protein which is highly homologous to the viral protein. cJun (previously known as the Fos binding protein p39) and c Fos form a complex in the nucleus. AP 1 (activating protein 1) is a collective term referring to these dimeric transcription factors composed of Jun, Fos or ATF subunits that bind to a common DNA site, the AP1 binding site. AP 1 proteins, mostly the Jun group, regulate the expression and function of cell cycle regulators such as Cyclin D1, p53, p21 (cip1/waf1), p19 (ARF) and p16. Fos and Jun proto oncogene expression is induced transiently by a variety of extracellular stimuli associated with mitogenesis, differentiation processes or depolarization of neurons. JUN has been mapped to 1p32 to p31, a chromosomal region involved in both translocations and deletions in human malignancies. Function: Transcription factor that recognizes and binds to the enhancer heptamer motif 5'-TGA[CG]TCA-3'. Promotes activity of NR5A1 when phosphorylated by HIPK3 leading to increased steroidogenic gene expression upon cAMP signaling pathway stimulation. Subunit: Heterodimer with either FOS or BATF3 or ATF7. The ATF7/JUN heterodimer is essential for ATF7 transactivation activity. Interacts with DSIPI; the interaction inhibits the binding of active AP1 to its target DNA. Interacts with HIVEP3 and MYBBP1A. Interacts with SP1, SPIB and TCF20. Interacts with COPS5; the interaction leads indirectly to its phosphorylation. Component of the SMAD3/SMAD4/JUN/FOS/complex which forms at the AP1 promoter site. The SMAD3/SMAD4 heterodimer acts syngernistically with the JUN/FOS heterodimer to activate transcription in response to TGF-beta. Interacts (via its basic DNA binding and leucine zipper domains) with SMAD3 (via an N-terminal domain); the interaction is required for TGF-beta-mediated transactivation of the SMAD3/SMAD4/JUN/FOS/complex. Interacts with RNF187. Binds to HIPK3. Subcellular Location: Nucleus. Post-translational modifications: Phosphorylated by CaMK4 and PRKDC; phosphorylation enhances the transcriptional activity. Phosphorylated by HIPK3. [PTM] Phosphorylated at Thr-239, Ser-243 and Ser-249 by GSK3B; phosphorylation reduces its ability to bind DNA. Phosphorylated by PAK2 at Thr-2, Thr-8, Thr-89, Thr-93 and Thr-286 thereby promoting JUN-mediated cell proliferation andtransformation. Similarity: Belongs to the bZIP family. Jun subfamily. Contains 1 bZIP domain. SWISS: P05412 Gene ID: 3725 |
