Auranofin targets UBA1 and enhances UBA1 activity by facilitating ubiquitin trans-thioesterificlation to E2 ubiquitin-conjugating enzymes

ABSTRACT: UBA1 is the primary E1 ubiquitin-activating enzyme, regulating stability and function of numerous proteins via initiating their ubiquitination. Decreased or insufficient ubiquitination can cause or drive aging and many deadly diseases. Therefore, a small-molecule UBA1 activity enhancer could have broad therapeutic potential. Here we report that auranofin, a drug approved for the treatment of rheumatoid arthritis is a potent UBA1 activity enhancer. Auranofin binds to the UBA1’s ubiquitin fold domain in vitro with a KD of 5.19 nM. The binding enhances UBA1 interactions with at least 20 different E2 ubiquitin-conjugating enzymes, facilitating ubiquitin charging to E2 and increasing the activities of five representative E3s in vitro. Auranofin promotes ubiquitination and degradation of misfolded ER proteins during ER-associated degradation in cells at low nanomolar concentrations. It also facilitates outer mitochondrial membrane-associated degradation. This study discovered the first small-molecule UBA1 activity enhancer, providing a much-needed tool for UBA1 research and therapeutic exploration.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Culture

SUBMITTER: Dingyin Tao  

LAB HEAD: Dingyin Tao

PROVIDER: PXD042558 | Pride | 2023-07-10

REPOSITORIES: Pride