Stat3 Mouse, Brilliant Violet 421, Clone: 49/p-Stat3, BD, Mouse Monoclonal Antibody, Each

Details

The 49/p-Stat3 monoclonal antibody recognizes the S727-phosphorylated form of Signal transducer and activator of transcription 3 (Stat3/STAT3 isoform 1). The fluorochrome-conjugated formats have been evaluated using a human model system. However, the unconjugated form of this antibody is also effective for western blot analysis of human, mouse, and rat tissue. The Stat proteins function both as cytoplasmic signal transducers and as activators of transcription. Seven mammalian Stat proteins have been identified: Stat1-4, Stat5a, 5b, and Stat6. Stat3 is a 92-kDa protein that is activated as a DNA binding protein through cytokines, such as IL-6, and growth factors, such as EGF. Stat3 is phophorylated at serine 727 (S727) via the MAPK pathway. The S727 residue is located at a conserved Pro-X-Ser-Pro sequence, which is recognized by the protein kinase ERK. Activation through the S727 residue is thought to lead to initiation of transcription. Upon activation, Stat3 dimerizes, translocates to the nucleus, and binds DNA response elements thereby regulating gene expression. It appears that Stat3 binds to DNA as a homodimer, but it is also capable of binding as a heterodimer with Stat1. In addition to serine phosphorylation, Stat3 is also phosphorylated at tyrosine 705 by JAK1 in response to cytokine stimulation. Stat3 is widely expressed and can bind to the sis-inducible element (SIE) site from the c-fos promoter. This site is similar to the GAS element that is present in IFN--induced genes. Thus, phosphorylation of S727 in Stat3 occurs in response to growth factors and cytokines, and is essential for normal transcriptional activity. The antibody was conjugated to BD Horizon BV421 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max of 407-nm and Em Max at 421-nm, BD Horizon BV421 can be excited by the violet laser and detected in the standard Pacific Blue™ filter set (eg, 450/50-nm filter). BD Horizon BV421 conjugates are very bright, often exhibiting a 10 fold improvement in brightness compared to Pacific Blue conjugates.