Catalog # RP2031

B-Raf (S446)/C-Raf (S338)/A-Raf (S299), phospho-Antibody

Rabbit Polyclonal

Application / Dilution

Size 100 μl

Species Reactivity Hu, Rt, Ms

MW 95 kDa



The Ras-Raf-MAP kinase signaling pathway is involved in control of cell proliferation and differentiation. The Raf kinase family includes A-Raf, B-Raf, and C-Raf. Each family member has three highly conserved regions (CR1-3). The N-terminal CR1 contains the Ras-GTP-binding domain. The CR2 contains a negative regulatory serine residue (C-Raf (S259)/B-Raf(S365)) that may bind 14-3-3 proteins. The CR3 is the catalytic domain that contains phosphorylation sites for Raf-regulating enzymes within two segments, the N-region and the activation segment. Activation of C-Raf involves phosphorylation at many sites including Ser-338, Tyr-341, and multiple catalytic domain sites. In B-Raf, multiple phosphorylation sites have been identified, but their specific roles are uncertain. Phosphorylation of Ser-446 may prime B-Raf for activation, and Ser-446 and/or Ser-447 phosphorylation may be critical for B-Raf biological activity during PC12 differentiation. Ser-579 is required for growth factor activation and kinase activity. Thus, multiple sites of phosphorylation within Rafs may be important for regulation of their activity.


Brummer, T. et al. (2006) Oncogene 25(47):6262.
Karbowniczek, M. et al. (2006) J Biol Chem 281(35):25447.
Wilhelm, S.M. et al. (2004) Cancer Res 64:7099.
Mason, C.S. et al. (1999) EMBOJ 18(8):2137.

Western blot of human Jurkat cells treated with calyculin A (100 nM) for 30 min. The blots were untreated (lanes 1 & 3) or treated (lanes 2 & 4) with lambda phosphatase and probed with anti-B-Raf (N-terminus) (lanes 1 & 2) or anti-B-Raf (Ser-446) (lanes 3 & 4).

Phospho-B-Raf (Ser-446) synthetic peptide (coupled to KLH) corresponds to amino acids surrounding serine 446 in human B-Raf. This sequence is conserved in B-Rafs from many species, and has high homology to C-Raf (Ser-338) and A-Raf (Ser-299).

*For more information, see UniProt Accession P15056
Rabbit polyclonal, affinity-purified antibody is supplied in 100µl phosphate-buffered saline, 50% glycerol, 1 mg/ml BSA, and 0.05% sodium azide. Store at –20°C. Stable for 1 year.

The products are are safely shipped at ambient temperature for both domestic and international shipments. Each product is guaranteed to match the specifications as indicated on the corresponding technical data sheet. Please store at -20C upon arrival for long term storage.

This antibody was cross-adsorbed to phospho-B-Raf (Ser-579) peptide before affinity purification using phospho-B-Raf (Ser-446) peptide. The purified antibody detects a strong band at 95 kDa* and a weaker band at 105 kDa in western blots of human Jurkat or A431 cells treated with Calyculin A. The antibody also detects other phosphorylated proteins at 150 and 200 kDa in calyculin A treated cells.

*All molecular weights (MW) are confirmed by comparison to Bio-Rad Rainbow Markers and to western blot mobilities of known proteins with similar MW.

This kit contains: