2-Phenylethynesulfonamide

DescriptionIn addition to its transactivational functions, p53 mediates apoptosis by binding with the anti-apoptotic proteins Bcl-xL and Bcl-2 at the mitochondrial surface. Pifithrin-μ (PFT-μ) is an inhibitor of p53-mediated apoptosis, preventing p53 binding to Bcl-xL and Bcl-2 at the mitochondria without affecting p53 transactivational activities In vitro, PFT-μ binds both p53 (Kd = 0.82 mM) and Bcl-xL (Kd = 0.80 mM). PFT-μ reduces p53-mediated apoptosis induced by γ-radiation in mouse thymocytes in vitro and protects mice from doses of radiation that cause lethal hematopoietic syndrome. At 25 μM, PFT-μ reduces apoptosis triggered by nutlin-3, which inhibits MDM2/p53 binding and potentiates p53-mediated growth arrest and apoptosis. PFT-μ also interacts selectively with heat shock protein 70 (Hsp70), leading to disruption of the association between Hsp70 and many of its co-chaperones and substrate proteins.

UsesA small molecule inhibitor of p53 binding to mitochondria protects mice from gamma radiation

UsesPifithrin-μ has been used:to treat microglial cell line to analyse its neuroprotective effect on M1-like and M2-like phenotypeas heat shock protein (HSP)-70 inhibitor, to treat transfected Marc-145 cellsto inhibit heat shock cognate 70 (Hsc70) to elucidate heat shock chaperones mouse embryonic stem cells

General DescriptionA cell-permeable sulfonamide that blocks p53 interaction with Bcl-xL and Bcl-2 proteins and selectively inhibits p53 translocation to mitochondria without affecting the transactivation function of p53. Effectively protects against γ radiation-induced cell death in vitro and animal lethality in vivo. Because Pifithrin-μ targets only the mitochondrial branch of the p53 pathway without affecting the important transcriptional functions of p53, it is superior to Pifithrin-α (Cat. No. 506132) in in vivo studies. Shown to selectively interact with inducible HSP70 and disrupt its functions.