NSC-624206

NSC 624206 (CAS No. 13116-77-3) is a selective inhibitor of the ubiquitin-activating enzyme (E1), specifically targeting the UBA1 enzyme. This enzyme catalyzes the initial step in the ubiquitin-proteasome system, a crucial process for regulating protein degradation and turnover.

Target and Mechanism of Action

• Primary Target: Ubiquitin-activating enzyme (UBA1/E1)

• Mechanism:

  • NSC 624206 inhibits the formation of the ubiquitin-thioester bond during ubiquitination.

  • Importantly, it does not inhibit the adenylation step of ubiquitin activation.

• Effect: By blocking UBA1 activity, it prevents the ubiquitination of substrate proteins, leading to altered protein turnover in cells.

Biological Effects

• p27 Stabilization:

  • p27, a tumor suppressor protein, is normally degraded via the ubiquitin-proteasome system.

  • NSC 624206 prevents p27 ubiquitination, resulting in accumulation of p27, which can inhibit cell cycle progression.

• IC₅₀: ~9 µM for UBA1 inhibition in vitro.

• Cellular Effects:

  • Inhibition of UBA1 can modulate proteostasis, potentially inducing cell cycle arrest in cancer cell lines.

  • May affect other proteins regulated by ubiquitination, though specificity is primarily toward E1.

Research Applications

• Used in cancer biology studies to investigate the role of ubiquitination in tumor suppressor regulation.

• Tool compound for studying protein degradation pathways and ubiquitin-dependent signaling.

• Can help in screening or validation of other inhibitors targeting the ubiquitin-proteasome system.

Structural Insights

Crystallographic studies have revealed that NSC 624206 binds to a specific site on the UBA1 enzyme, providing insights into its inhibitory mechanism. These structural details are valuable for designing more potent and selective inhibitors targeting the ubiquitin-activating enzyme. RSC PublishingBiocrick+3ScienceDirect+3ScienceDirect+3