Multi-species study identifies the vacuolar H+ ATPase component ATP6V0C as a human disease-associated gene

Brain. 2022 Sep 8:awac330. doi: 10.1093/brain/awac330

ATP6V0C variants impair vacuolar V-ATPase causing a neurodevelopmental disorder
often associated with epilepsy

Mattison KA, Tossing G, Mulroe F, Simmons C, Butler KM, Schreiber A, Alsadah A, Neilson DE, Naess K, Wedell A, Wredenberg A, Sorlin A, McCann E, Burghel GJ, Menendez B, Hoganson GE, Botto LD, Filloux FM, Aledo-Serrano Á, Gil-Nagel A, Tatton-Brown K, Verbeek NE, van Hirtum-Das M, Breckpot J, Hammer TB, Møller RS, Whitney A, Douglas AGL, Kharbanda M, Brunetti-Pierri N, Morleo M, Nigro V, May HJ, Tao JX, Argili E, Sherr EH, Dobyns WB, Consortium GER, Baines RA, Warwicker J, Parker JA, Banka S, Campeau PM, Escayg A

Abstract:

The vacuolar H+-ATPase (V-ATPase) is an enzymatic complex that functions in an ATP-dependent manner to pump protons across membranes and acidify organelles, thereby creating the proton/pH gradient required for membrane trafficking by several different types of transporters. We describe heterozygous point variants in ATP6V0C, encoding the c-subunit in the membrane bound integral domain of the V-ATPase, in 27 patients with neurodevelopmental abnormalities with or without epilepsy. Corpus callosum hypoplasia and cardiac abnormalities were also present in some patients. In silico modeling suggested that the patient variants interfere with the interactions between the ATP6V0C and ATP6V0A subunits during ATP hydrolysis. Consistent with decreased V-ATPase activity, functional analyses conducted in Saccharomyces cerevisiae revealed reduced LysoSensor fluorescence and reduced growth in media containing varying concentrations of CaCl2. Knockdown of ATP6V0C in Drosophila resulted in increased duration of seizure-like behavior, and the expression of selected patient variants in Caenorhabditis elegans led to reduced growth, motor dysfunction, and reduced lifespan. In summary, this study establishes ATP6V0C as an important disease gene, describes the clinical features of the associated neurodevelopmental disorder, and provides insight into disease mechanisms.

DOI: 10.1093/brain/awac330
PMID: 36074901