Phospho-c-Myc (Thr58) Recombinant Rabbit mAb (S-1060-277)

Phospho-c-Myc (Thr58) refers to the modified form of the transcription factor c-Myc generated upon phosphorylation at the Thr58 residue, and represents a core molecular event regulating c-Myc protein stability and degradation. Phosphorylation at this site is catalyzed by glycogen synthase kinase-3 (GSK-3) and requires prior phosphorylation at Ser62 as a "priming" signal. Following Thr58 phosphorylation, c-Myc is recognized by the Fbw7-SCF ubiquitin ligase complex, undergoes polyubiquitination, and is rapidly degraded via the proteasome pathway. In terms of functional consequences, Thr58 is a mutational hotspot in aggressive lymphomas such as Burkitt lymphoma; mutation at this site abolishes phosphorylation and markedly increases protein stability, thereby enhancing the transforming potential of c-Myc. In addition, Thr58 phosphorylation alters the subnuclear localization of c-Myc, enhancing its accumulation in discrete nuclear bodies. In experimental detection, the Thr58 phosphorylation level is often used as an indicator of the integrity of the c-Myc degradation pathway: reduced or absent phosphorylation at this site suggests abnormally increased c-Myc protein stability, which may be associated with tumorigenesis.