{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nCHMP3 is a core ESCRT‐III subunit that orchestrates critical membrane scission events. In conjunction with CHMP2A, it polymerizes into helical tubular structures that help drive inward membrane budding during multivesicular body (MVB) formation, cytokinetic abscission, and the release of enveloped viruses. Its activity is tightly regulated by an autoinhibitory mechanism—mediated by its C‐terminal acidic domain and the folding back of the downstream α5 helix—that is relieved by interactions with factors such as the AAA‐ATPase VPS4 and the deubiquitinating enzyme AMSH, thereby promoting proper ESCRT‐III assembly at membranes."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "1", "end_ref": "3"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn endosomal protein sorting, CHMP3 (also known as VPS24) localizes predominantly to late endosomes where its function supports the trafficking and degradation of ubiquitinated receptors such as the epidermal growth factor receptor (EGFR). Disruption of CHMP3 impairs MVB formation—for example resulting in smaller multivesicular endosomes that compromise receptor delivery to lysosomes—yet may not necessarily alter receptor signaling termination. Its interactions with other components (including CHMP1B and selective binding motifs that engage the MIT domains of regulatory proteins like AMSH) as well as its ability to bind specific phosphoinositides further underscore its role in membrane remodeling and endosome dynamics."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "4", "end_ref": "8"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nEmerging studies have linked CHMP3 to disease-related cellular processes. In certain contexts, alternative or retrotransposed forms of CHMP3—as well as engineered truncated variants known as retroCHMP3 proteins—act as potent inhibitors of viral budding, thereby restricting the egress of retroviruses, paramyxoviruses, and filoviruses without compromising essential cellular ESCRT functions. In tumor biology, reduced expression of CHMP3 (for instance via miRNA-mediated suppression) correlates with enhanced epithelial–mesenchymal transition (EMT) and activation of mitogen-activated protein kinase (MAPK) signaling in triple-negative breast cancer, whereas in liver cancer, CHMP3 levels have been associated with modulation of pyroptosis and poor patient prognosis. Notably, an alternatively spliced variant, Vps24β, lacking the N-terminal lipid-binding domain, exhibits anti-apoptotic properties by counteracting Bax-mediated cell death."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "9", "end_ref": "13"}]}, {"type": "t", "text": "\n"}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Suman Lata, Guy Schoehn, Ankur Jain, et al. 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