Species predicted to react based on 100% sequence homology:Chicken
Specificity / Sensitivity
Phospho-Fox03a (Ser318/321) Antibody detects endogenous levels of Fox03a only when phosphorylated at serine 318/321. The antibody is expected to cross-react with Fox01 when phosphorylated at serine 322/325 based on the peptide sequence.
Source / Purification
Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to the sequence of human Fox03a. Antibodies are purified by protein A and peptide affinity chromatography.
Background
The Forkhead family of transcription factors is involved in tumorigenesis of rhabdomyosarcoma and acute leukemias (1-3). Within the family, three members (FoxO1, FoxO4, and FoxO3a) have sequence similarity to the nematode orthologue DAF-16, which mediates signaling via a pathway involving IGFR1, PI3K, and Akt (4-6). Active forkhead members act as tumor suppressors by promoting cell cycle arrest and apoptosis. Increased expression of any FoxO member results in the activation of the cell cycle inhibitor p27 Kip1. Forkhead transcription factors also play a part in TGF-β-mediated upregulation of p21 Cip1, a process negatively regulated through PI3K (7). Increased proliferation results when forkhead transcription factors are inactivated through phosphorylation by Akt at Thr24, Ser256, and Ser319, which results in nuclear export and inhibition of transcription factor activity (8). Forkhead transcription factors can also be inhibited by the deacetylase sirtuin (SirT1) (9).Phosphorylation sites Ser322 and Ser325 of Fox01 are important for nuclear export and are homologous to Ser318 and Ser321 of Fox03a (9).