9y06
Cryo-EM structure of human VCP/p97-T122P mutant bound to ADP
Structural highlights
DiseaseTERA_HUMAN Defects in VCP are the cause of inclusion body myopathy with early-onset Paget disease and frontotemporal dementia (IBMPFD) [MIM:167320; also known as muscular dystrophy, limb-girdle, with Paget disease of bone or pagetoid amyotrophic lateral sclerosis or pagetoid neuroskeletal syndrome or lower motor neuron degeneration with Paget-like bone disease. IBMPFD features adult-onset proximal and distal muscle weakness (clinically resembling limb girdle muscular dystrophy), early-onset Paget disease of bone in most cases and premature frontotemporal dementia.[1] [2] [3] [4] [5] Defects in VCP are the cause of amyotrophic lateral sclerosis type 14 with or without frontotemporal dementia (ALS14) [MIM:613954. ALS14 is a neurodegenerative disorder affecting upper motor neurons in the brain and lower motor neurons in the brain stem and spinal cord, resulting in fatal paralysis. Sensory abnormalities are absent. The pathologic hallmarks of the disease include pallor of the corticospinal tract due to loss of motor neurons, presence of ubiquitin-positive inclusions within surviving motor neurons, and deposition of pathologic aggregates. The etiology of amyotrophic lateral sclerosis is likely to be multifactorial, involving both genetic and environmental factors. The disease is inherited in 5-10% of the cases. Patients with ALS14 may develop frontotemporal dementia.[6] FunctionTERA_HUMAN Necessary for the fragmentation of Golgi stacks during mitosis and for their reassembly after mitosis. Involved in the formation of the transitional endoplasmic reticulum (tER). The transfer of membranes from the endoplasmic reticulum to the Golgi apparatus occurs via 50-70 nm transition vesicles which derive from part-rough, part-smooth transitional elements of the endoplasmic reticulum (tER). Vesicle budding from the tER is an ATP-dependent process. The ternary complex containing UFD1L, VCP and NPLOC4 binds ubiquitinated proteins and is necessary for the export of misfolded proteins from the ER to the cytoplasm, where they are degraded by the proteasome. The NPLOC4-UFD1L-VCP complex regulates spindle disassembly at the end of mitosis and is necessary for the formation of a closed nuclear envelope. Regulates E3 ubiquitin-protein ligase activity of RNF19A (By similarity). Component of the VCP/p97-AMFR/gp78 complex that participates in the final step of the sterol-mediated ubiquitination and endoplasmic reticulum-associated degradation (ERAD) of HMGCR. Also involved in DNA damage response: recruited to double-strand breaks (DSBs) sites in a RNF8- and RNF168-dependent manner and promotes the recruitment of TP53BP1 at DNA damage sites. Recruited to stalled replication forks by SPRTN: may act by mediating extraction of DNA polymerase eta (POLH) to prevent excessive translesion DNA synthesis and limit the incidence of mutations induced by DNA damage.[7] [8] [9] [10] [11] [12] [13] Publication Abstract from PubMedPURPOSE: Adams-Oliver syndrome (AOS) is a genetically heterogeneous disorder with cardinal features of aplasia cutis congenita and terminal limb reduction defects. A minority of individuals with AOS develop potentially lethal pulmonary hypertension (PH) in infancy, a subgroup that has been refractory to genetic explanation. METHODS: We studied a cohort of individuals with AOS and no genetic diagnosis by genome and exome sequencing. We characterized rare identified substitution variants in valosin containing protein (VCP) in vitro using ATP hydrolysis, cryogenic-electron microscopy, thermal stability, and response to CB-5083, a VCP inhibitor. RESULTS: We report a new genetic etiology for AOS in 6 families with PH and 1 family without it. We show that AOS-related VCP variants are hypermorphic with respect to ATP hydrolysis and cause N-terminal domain hyperflexibility with impairment of interdomain coupling. Additionally, we find that CB-5083 inhibits the overactive ATP hydrolysis. Review of published cases of AOS with PH suggests that pulmonary veno-occlusive disease is the most common mechanism. Clinical risk factors for PH in AOS include CMTC, prominent dilated subcutaneous veins and intra-uterine growth restriction. CONCLUSION: We identify the prevalent genetic cause of pulmonary hypertension in AOS and highlight a potential therapeutic approach. Mutations in VCP cause Adams-Oliver syndrome with or without pulmonary hypertension.,Lehman A, Ahmed S, Mohajeri A, Berezuk AM, Mannar D, Cholak S, Tuttle KS, Bennett JT, Aparecida Magno J, Hannibal M, Kovacevic G, Kuburovic V, Suzanne Lewis ME, Moldovan O, Nelson Z, Raskin S, Vandersteen AM, Roach JC, Subramaniam S, Patel MS Genet Med. 2026 Apr 13:102579. doi: 10.1016/j.gim.2026.102579. PMID:41979051[14] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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