JunD (D17G2) Rabbit mAb #5000

JunD, along with closely related family members c-Jun and JunB, is a transcription factor that can activate or repress a wide array of target genes (1,2). JunD transcriptional activity is modulated by phosphorylation in response to cellular stress via the c-Jun N-terminal Kinase (JNK)/Stress-Activated Protein Kinase (SAPK) family of protein kinases (3,4). JunD activity can also be modulated by the MAPK pathway in response to growth factors. Its transcriptional capacity is further regulated by other binding partners that affect JunD expression levels and DNA binding capacity (reviewed in 2). All Jun proteins are capable of forming dimers with Fos-, ATF- and CREB-family transcription factors to form the AP-1 complex that differentially regulates a variety of target genes involved in cellular growth, proliferation, differentiation, and apoptosis (reviewed in 2 and 6). Unlike JunB and c-Jun, which share a high degree of homology (>95%), JunD is less conserved (~75%) at the amino acid level (1). Growing evidence suggests that JunD protein expression is regulated independently of other family members (reviewed in 2). It is thought that JunD may have functional significance beyond the typical Jun-family milieu. This is exemplified by the fact that JunD knockout mice are viable, bearing specific defects in cardiomyocyte function and bone growth, whereas their c-Jun counterparts develop significant, multi-organ defects during embryogenesis and die at E12.5 (6-9). JunD appears to specifically regulate genes involved in antioxidant response and hydrogen peroxide production and plays an important role in angiogenesis via its ability to exert transcriptional control over the VEGF gene (10). Furthermore, JunD appears to play an important roll in metabolism via modulation of IGF-I signaling pathways (11). Recent studies have shown that JunD regulates GADD45 α and γ expression in prostate cancer cells and that inhibition of JunD promotes apoptosis. Thus, JunD may be a viable therapeutic target for the treatment of prostate cancer (12).