Ubiquitin specific peptidase 9 X-linked (USP9X) mRNA (USP9X)

Ubiquitin specific peptidase 9 X-linked (USP9X) mRNA encodes a member of the peptidase C19 family that functions as a deubiquitinating enzyme (DUB) [1]. The encoded protein plays a pivotal role in regulating protein homeostasis by removing ubiquitin chains from various substrates, thereby preventing their proteasomal degradation [2]. In the context of oncology, USP9X is frequently overexpressed and acts as an oncoprotein by stabilizing pro-survival factors such as MCL1 and BCL2, which are critical for the survival of cancer cells and resistance to chemotherapy [3, 4]. Beyond its role in cancer, USP9X is essential for normal brain development and neuronal migration, with mutations in the gene being linked to X-linked intellectual disability [5]. Therapeutic strategies targeting this pathway include small molecule inhibitors like WP1130 that block the enzymatic activity of the protein, as well as RNA-targeted approaches like siRNA that aim to reduce the levels of the mRNA transcript [6]. However, the broad range of substrates regulated by USP9X presents challenges for drug development, as systemic inhibition may lead to significant safety concerns or off-target effects [1, 6].

Other names

FAMFAFXDFFRXMRX99Ubiquitin-specific-processing protease 9 X-chromosomeFat facets in Drosophila homolog

Inhibition of the deubiquitinating activity of the encoded protein or RNA interference (RNAi) mediated degradation of the mRNA transcript, leading to the depletion of pro-survival substrates like MCL1 [3, 4, 6].