{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,26]],"date-time":"2025-12-26T00:14:06Z","timestamp":1766708046840,"version":"3.48.0"},"reference-count":49,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,25]],"date-time":"2025-12-25T00:00:00Z","timestamp":1766620800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"investigator incentive funds from the University of Texas, El Paso"},{"name":"start-up funds from the University of Texas Arlington"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JDB"],"abstract":"<jats:p>Mutations in the transcriptional co-factor HCFC1 cause methylmalonic aciduria and homocystinemia, cblX type (cblX) (MIM#309541), non-syndromic X-linked intellectual disability (XLID), and focal epilepsy. Zebrafish studies have revealed increased activation of the Akt\/mTor signaling pathway after mutation of hcfc1a, one ortholog of HCFC1. mTOR hyperactivation is linked to seizures, and its inhibition alleviates epilepsy in other preclinical models. We hypothesized that mTor overactivity in hcfc1a mutant zebrafish increases seizure susceptibility and\/or severity. We employed a two-concentration model of the seizure-inducing agent, pentylenetetrazol (PTZ), with or without pretreatment of the mTor inhibitor, torin1. Mutation of hcfc1a did not alter the response to PTZ at sub-optimal concentrations, and the pharmaceutical inhibition of mTor using the compound Torin1 reduced response to 1 \u00b5M PTZ, but only in a dose-dependent manner. Higher doses of mTor inhibition did not reduce the seizure response in mutant larvae but were effective in wildtype siblings. These data suggest that inhibition of mTor in an hcfc1a-deficient background leads to a reaction that differs from the traditional response observed in wildtype siblings. Collectively, we present a model that can be used to test dose\u2013response and the development of combinatorial treatment approaches in a high-throughput manner.<\/jats:p>","DOI":"10.3390\/jdb14010002","type":"journal-article","created":{"date-parts":[[2025,12,25]],"date-time":"2025-12-25T23:52:27Z","timestamp":1766706747000},"page":"2","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Zebrafish Seizure Model of cblX Syndrome Reveals a Dose-Dependent Response to mTor Inhibition"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-5980-003X","authenticated-orcid":false,"given":"Claudia B.","family":"Gil","sequence":"first","affiliation":[{"name":"Department of Biology, University of Texas Arlington, 701 S Nedderman Dr., Arlington, TX 76019, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Paz","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, The University of Texas El Paso, 500 West University Ave, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Briana E.","family":"Pinales","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, The University of Texas El Paso, 500 West University Ave, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Victoria L.","family":"Castro","sequence":"additional","affiliation":[{"name":"Department of Developmental Neurobiology, St. Jude Children\u2019s Research Hospital, 262 Danny Thomas Dr., Memphis, TN 38105, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claire E.","family":"Perucho","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, The University of Texas El Paso, 500 West University Ave, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Annalise","family":"Gonzales","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, The University of Texas El Paso, 500 West University Ave, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3752-3070","authenticated-orcid":false,"given":"Giulio","family":"Francia","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, The University of Texas El Paso, 500 West University Ave, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sepiso K.","family":"Masenga","sequence":"additional","affiliation":[{"name":"Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7730-952X","authenticated-orcid":false,"suffix":"Jr.","given":"Antentor","family":"Hinton","sequence":"additional","affiliation":[{"name":"Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3596-1587","authenticated-orcid":false,"given":"Anita M.","family":"Quintana","sequence":"additional","affiliation":[{"name":"Department of Biology, University of Texas Arlington, 701 S Nedderman Dr., Arlington, TX 76019, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1101\/gr.150078.112","article-title":"HCFC1 Is a Common Component of Active Human CpG-Island Promoters and Coincides with ZNF143, THAP11, YY1, and GABP Transcription Factor Occupancy","volume":"23","author":"Michaud","year":"2013","journal-title":"Genome Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"506","DOI":"10.1016\/j.ajhg.2013.07.022","article-title":"An X-Linked Cobalamin Disorder Caused by Mutations in Transcriptional Coregulator HCFC1","volume":"93","author":"Yu","year":"2013","journal-title":"Am. J. Hum. Genet."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"694","DOI":"10.1016\/j.ajhg.2012.08.011","article-title":"A Noncoding, Regulatory Mutation Implicates HCFC1 in Nonsyndromic Intellectual Disability","volume":"91","author":"Huang","year":"2012","journal-title":"Am. J. Hum. Genet."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3335","DOI":"10.1093\/hmg\/ddv083","article-title":"HCFC1 Loss-of-Function Mutations Disrupt Neuronal and Neural Progenitor Cells of the Developing Brain","volume":"24","author":"Jolly","year":"2015","journal-title":"Hum. Mol. Genet."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"215","DOI":"10.3892\/br.2015.559","article-title":"A Novel HCFC1 Variant in Male Siblings with Intellectual Disability and Microcephaly in the Absence of Cobalamin Disorder","volume":"4","author":"Koufaris","year":"2016","journal-title":"Biomed. Rep."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"717","DOI":"10.1038\/s10038-020-00892-9","article-title":"Novel Exon-Skipping Variant Disrupting the Basic Domain of HCFC1 Causes Intellectual Disability without Metabolic Abnormalities in Both Male and Female Patients","volume":"66","author":"Wongkittichote","year":"2021","journal-title":"J. Hum. Genet."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"e1289","DOI":"10.1002\/ctm2.1289","article-title":"HCFC1 Variants in the Proteolysis Domain Are Associated with X-Linked Idiopathic Partial Epilepsy: Exploring the Underlying Mechanism","volume":"13","author":"He","year":"2023","journal-title":"Clin. Transl. Med."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2838","DOI":"10.1093\/hmg\/ddx157","article-title":"Mutations in THAP11 Cause an Inborn Error of Cobalamin Metabolism and Developmental Abnormalities","volume":"26","author":"Quintana","year":"2017","journal-title":"Hum. Mol. Genet."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Castro, V.L., Reyes, J.F., Reyes-Nava, N.G., Paz, D., and Quintana, A.M. (2020). Hcfc1a Regulates Neural Precursor Proliferation and Asxl1 Expression in the Developing Brain. BMC Neurosci., 21.","DOI":"10.1186\/s12868-020-00577-1"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"578","DOI":"10.1002\/dneu.22704","article-title":"Cortical and Commissural Defects Upon HCF-1 Loss in Nkx2.1-Derived Embryonic Neurons and Glia","volume":"79","author":"Minocha","year":"2019","journal-title":"Dev. Neurobiol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"134","DOI":"10.1038\/s41467-021-27759-7","article-title":"Mutations in Hcfc1 and Ronin Result in an Inborn Error of Cobalamin Metabolism and Ribosomopathy","volume":"13","author":"Chern","year":"2022","journal-title":"Nat. Commun."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"5198","DOI":"10.1038\/s41598-017-05564-x","article-title":"Asxl1 Deficiency in Embryonic Fibroblasts Leads to Cellular Senescence via Impairment of the AKT-E2F Pathway and Ezh2 Inactivation","volume":"7","author":"Youn","year":"2017","journal-title":"Sci. Rep."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1613","DOI":"10.1093\/brain\/awv045","article-title":"PI3K\/AKT Pathway Mutations Cause a Spectrum of Brain Malformations from Megalencephaly to Focal Cortical Dysplasia","volume":"138","author":"Jansen","year":"2015","journal-title":"Brain"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"147290","DOI":"10.1016\/j.gene.2023.147290","article-title":"Missense and Nonsense Mutations of the Zebrafish Hcfc1a Gene Result in Contrasting mTor and Radial Glial Phenotypes","volume":"864","author":"Castro","year":"2023","journal-title":"Gene"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"7364","DOI":"10.1038\/s41467-023-42922-y","article-title":"Targeted Suppression of mTORC2 Reduces Seizures across Models of Epilepsy","volume":"14","author":"Okoh","year":"2023","journal-title":"Nat. Commun."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"107713","DOI":"10.1016\/j.yebeh.2020.107713","article-title":"Genetic Pathogenesis of the Epileptogenic Lesions in Tuberous Sclerosis Complex: Therapeutic Targeting of the mTOR Pathway","volume":"131","author":"Moavero","year":"2022","journal-title":"Epilepsy Behav."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1016\/j.seizure.2014.04.001","article-title":"A Novel TSC2 Mutation Causing Tuberless Tuberous Sclerosis","volume":"23","author":"Giannantoni","year":"2014","journal-title":"Seizure"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1790","DOI":"10.1002\/acn3.51868","article-title":"Seizure Reduction in TSC2-Mutant Mouse Model by an mTOR Catalytic Inhibitor","volume":"10","author":"Dhamne","year":"2023","journal-title":"Ann. Clin. Transl. Neurol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.ejmg.2014.12.015","article-title":"Multiple Congenital Anomalies in Two Boys with Mutation in HCFC1 and Cobalamin Disorder","volume":"58","author":"Morin","year":"2015","journal-title":"Eur. J. Med. Genet."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1573","DOI":"10.1007\/s11011-021-00823-3","article-title":"PTZ Kindling Model for Epileptogenesis, Refractory Epilepsy, and Associated Comorbidities: Relevance and Reliability","volume":"36","author":"Singh","year":"2021","journal-title":"Metab. Brain Dis."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1016\/j.pnpbp.2003.09.026","article-title":"Anticonvulsant and Antiepileptogenic Effects of GABAA Receptor Ligands in Pentylenetetrazole-Kindled Mice","volume":"28","author":"Hansen","year":"2004","journal-title":"Prog. Neuropsychopharmacol. Biol. Psychiatry"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"759","DOI":"10.1016\/j.neuroscience.2004.11.031","article-title":"Pentylenetetrazole Induced Changes in Zebrafish Behavior, Neural Activity and c-Fos Expression","volume":"131","author":"Baraban","year":"2005","journal-title":"Neuroscience"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Afrikanova, T., Serruys, A.-S.K., Buenafe, O.E.M., Clinckers, R., Smolders, I., de Witte, P.A.M., Crawford, A.D., and Esguerra, C.V. (2013). Validation of the Zebrafish Pentylenetetrazol Seizure Model: Locomotor versus Electrographic Responses to Antiepileptic Drugs. PLoS ONE, 8.","DOI":"10.1371\/journal.pone.0054166"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Milder, P.C., Zybura, A.S., Cummins, T.R., and Marrs, J.A. (2022). Neural Activity Correlates with Behavior Effects of Anti-Seizure Drugs Efficacy Using the Zebrafish Pentylenetetrazol Seizure Model. Front. Pharmacol., 13.","DOI":"10.3389\/fphar.2022.836573"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"109594","DOI":"10.1016\/j.jneumeth.2022.109594","article-title":"Optimization of a Locomotion-Based Zebrafish Seizure Model","volume":"375","author":"Shaw","year":"2022","journal-title":"J. Neurosci. Methods"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Szep, D., Dittrich, B., Gorbe, A., Szentpeteri, J.L., Aly, N., Jin, M., Budan, F., and Sik, A. (2023). A Comparative Study to Optimize Experimental Conditions of Pentylenetetrazol and Pilocarpine-Induced Epilepsy in Zebrafish Larvae. PLoS ONE, 18.","DOI":"10.1371\/journal.pone.0288904"},{"key":"ref_27","first-page":"e53297","article-title":"High Throughput Danio Rerio Energy Expenditure Assay","volume":"107","author":"Williams","year":"2016","journal-title":"J. Vis. Exp."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1016\/j.neuro.2008.09.011","article-title":"Locomotion in Larval Zebrafish: Influence of Time of Day, Lighting and Ethanol","volume":"30","author":"MacPhail","year":"2009","journal-title":"Neurotoxicology"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1016\/j.toxlet.2017.05.021","article-title":"Toxicant Induced Behavioural Aberrations in Larval Zebrafish Are Dependent on Minor Methodological Alterations","volume":"276","author":"Fraser","year":"2017","journal-title":"Toxicol. Lett."},{"key":"ref_30","first-page":"bio051367","article-title":"Abnormal Expression of GABAA Receptor Sub-Units and Hypomotility upon Loss of Gabra1 in Zebrafish","volume":"9","author":"Yu","year":"2020","journal-title":"Biol. Open"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"100790","DOI":"10.1016\/j.diff.2024.100790","article-title":"Characterization of the Zebrafish Gabra1sa43718\/Sa43718 Germline Loss of Function Allele Confirms a Function for Gabra1 in Motility and Nervous System Development","volume":"138","author":"Paz","year":"2024","journal-title":"Differentiation"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Hoyberghs, J., Bars, C., Ayuso, M., Van Ginneken, C., Foubert, K., and Van Cruchten, S. (2021). DMSO Concentrations up to 1% Are Safe to Be Used in the Zebrafish Embryo Developmental Toxicity Assay. Front. Toxicol., 3.","DOI":"10.3389\/ftox.2021.804033"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"134490","DOI":"10.1016\/j.scitotenv.2019.134490","article-title":"DMSO Effects Larval Zebrafish (Danio Rerio) Behavior, with Additive and Interaction Effects When Combined with Positive Controls","volume":"709","author":"Christou","year":"2020","journal-title":"Sci. Total Env."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Hagen, E.V., Harper, M.M.M., Zhang, Y., and Hamilton, T.J. (2025). Exploring the Impact of Acute Solvent Exposure on Larval Zebrafish Behaviour. Front. Behav. Neurosci., 19.","DOI":"10.3389\/fnbeh.2025.1717998"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1089\/zeb.2012.0861","article-title":"Towards a Comprehensive Catalog of Zebrafish Behavior 1.0 and Beyond","volume":"10","author":"Kalueff","year":"2013","journal-title":"Zebrafish"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"8023","DOI":"10.1074\/jbc.M900301200","article-title":"An ATP-Competitive Mammalian Target of Rapamycin Inhibitor Reveals Rapamycin-Resistant Functions of mTORC1","volume":"284","author":"Thoreen","year":"2009","journal-title":"J. Biol. Chem."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"dmm049080","DOI":"10.1242\/dmm.049080","article-title":"A Zebrafish-Centric Approach to Antiepileptic Drug Development","volume":"14","author":"Baraban","year":"2021","journal-title":"Dis. Model. Mech."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.neubiorev.2020.06.010","article-title":"Seizing the Moment: Zebrafish Epilepsy Models","volume":"116","author":"Gawel","year":"2020","journal-title":"Neurosci. Biobehav. Rev."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1016\/j.brainres.2012.02.022","article-title":"Distinct Models of Induced Hyperactivity in Zebrafish Larvae","volume":"1449","author":"Ellis","year":"2012","journal-title":"Brain Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"987","DOI":"10.1016\/0091-3057(91)90116-J","article-title":"Pentylenetetrazole Can Induce a Conditioned Place Preference","volume":"40","author":"Gauvin","year":"1991","journal-title":"Pharmacol. Biochem. Behav."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"734","DOI":"10.1134\/S1819712424700399","article-title":"Anxiogenic Effect of Pentylenetetrazole at a Subconvulsive Dose Is Accompanied by Decreased Cellular Proliferation and Neuronal NO-Synthase Expression in the Posterior Part of the Hippocampus","volume":"18","author":"Aniol","year":"2024","journal-title":"Neurochem. J."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"334","DOI":"10.1038\/s41583-024-00805-1","article-title":"mTOR and Neuroinflammation in Epilepsy: Implications for Disease Progression and Treatment","volume":"25","author":"Ravizza","year":"2024","journal-title":"Nat. Rev. Neurosci."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Boff, M.O., Xavier, F.A.C., Diz, F.M., Gon\u00e7alves, J.B., Ferreira, L.M., Zambeli, J., Pazzin, D.B., Previato, T.T.R., Erwig, H.S., and Gon\u00e7alves, J.I.B. (2025). mTORopathies in Epilepsy and Neurodevelopmental Disorders: The Future of Therapeutics and the Role of Gene Editing. Cells, 14.","DOI":"10.3390\/cells14090662"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"3568","DOI":"10.36922\/an.3568","article-title":"mTOR Inhibition in Epilepsy: A Literature Review","volume":"3","author":"Teng","year":"2024","journal-title":"Adv. Neurol."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1016\/j.bbapap.2007.08.015","article-title":"Role of mTOR in Physiology and Pathology of the Nervous System","volume":"1784","author":"Swiech","year":"2008","journal-title":"Biochim. Biophys. Acta"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"49","DOI":"10.2217\/fnl-2018-0001","article-title":"The mTOR Pathway in Treatment of Epilepsy: A Clinical Update","volume":"13","author":"Griffith","year":"2018","journal-title":"Future Neurol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1016\/j.bbrc.2018.12.047","article-title":"Asxl1 Ablation in Mouse Embryonic Stem Cells Impairs Neural Differentiation without Affecting Self-Renewal","volume":"508","author":"An","year":"2019","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1327","DOI":"10.1038\/s41375-018-0083-3","article-title":"A Novel ASXL1-OGT Axis Plays Roles in H3K4 Methylation and Tumor Suppression in Myeloid Malignancies","volume":"32","author":"Inoue","year":"2018","journal-title":"Leukemia"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"e58737","DOI":"10.7554\/eLife.58737","article-title":"mTOR Signaling Regulates the Morphology and Migration of Outer Radial Glia in Developing Human Cortex","volume":"9","author":"Andrews","year":"2020","journal-title":"eLife"}],"container-title":["Journal of Developmental Biology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2221-3759\/14\/1\/2\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,26]],"date-time":"2025-12-26T00:13:05Z","timestamp":1766707985000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2221-3759\/14\/1\/2"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12,25]]},"references-count":49,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,3]]}},"alternative-id":["jdb14010002"],"URL":"https:\/\/doi.org\/10.3390\/jdb14010002","relation":{},"ISSN":["2221-3759"],"issn-type":[{"value":"2221-3759","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,12,25]]}}}