Non-phospho (Active) β-Catenin (Ser33/37/Thr41) Recombinant Rabbit mAb (S-3501)

Non-phospho (Active) β-Catenin (Ser33/37/Thr41) refers to the stable, transcriptionally competent pool of β-catenin that escapes degradation by the destruction complex, serving as a critical indicator of canonical Wnt signaling pathway activation. Under basal conditions, β-catenin is phosphorylated at serine 33, serine 37, and threonine 41 by glycogen synthase kinase-3β (GSK-3β) and casein kinase 1α (CK1α), which marks it for ubiquitination by the E3 ligase β-TrCP and subsequent proteasomal degradation; however, upon Wnt ligand binding to Frizzled and LRP5/6 receptors, this phosphorylation is inhibited, allowing β-catenin to accumulate in the cytoplasm in its non-phosphorylated form. This specific non-phosphorylated state enables β-catenin to translocate into the nucleus, where it interacts with T-cell factor/lymphoid enhancer factor (TCF/LEF) transcription factors to drive the expression of target genes involved in cell proliferation, differentiation, and stem cell maintenance, making this protein variant a pivotal biomarker for studying Wnt pathway dysregulation in various cancers and developmental disorders.