{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T17:37:29Z","timestamp":1779125849934,"version":"3.51.4"},"reference-count":46,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,9,25]],"date-time":"2025-09-25T00:00:00Z","timestamp":1758758400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Neurosci."],"abstract":"<jats:sec><jats:title>Introduction<\/jats:title><jats:p>Microtubules are essential components of the neuronal cytoskeleton. The <jats:italic>\u03b1<\/jats:italic>- and <jats:italic>\u03b2<\/jats:italic>-tubulins, variably expressed in the central nervous system, play key roles in neurogenesis and brain development. Pathogenic variants in <jats:italic>TUBB2A<\/jats:italic> have recently been identified as an ultra-rare cause of pediatric neurodevelopmental disorders (NDDs). However, the neurological and behavioral manifestations, genotype\u2013phenotype correlations, and underlying disease mechanisms remain poorly understood due to the limited number of reported families.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>We describe a cohort of families presenting with microcephaly, global developmental delay, speech impairment, seizures and\/or EEG abnormalities, movement disorders and severe behavioral disorders. Clinical assessments and brain imaging studies were conducted over a 10-year follow-up period. Genetic analysis was performed via whole-exome sequencing (WES), and structural modeling was used to investigate the functional impact of the identified variants.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>WES revealed a novel recurrent heterozygous pathogenic variant in <jats:italic>TUBB2A<\/jats:italic> (NM_001069.3:c.1172G\u202f&amp;gt;\u202fA; NP_001060.1:p.Arg391His), identified as the cause of disease in multiple affected individuals from unrelated families. Comparative analysis with previously reported <jats:italic>TUBB2A de novo<\/jats:italic> variants confirmed that this novel recurrent mutation affects a highly conserved Arg391 residue within the longitudinal E-site heterodimer interface. Computational modeling demonstrated that the variant disrupts <jats:italic>\u03b1<\/jats:italic>\/<jats:italic>\u03b2<\/jats:italic>-tubulin heterodimer formation, impairing binding stability at this critical interaction site.<\/jats:p><\/jats:sec><jats:sec><jats:title>Discussion<\/jats:title><jats:p>Our findings expand the phenotypic and genotypic spectrum of <jats:italic>TUBB2A<\/jats:italic>-related disorders and identify Arg391 as a mutational hotspot linked to severe brain developmental disorders due to aberrant tubulin dynamics, highlighting the disruption of the <jats:italic>\u03b1<\/jats:italic>\/<jats:italic>\u03b2<\/jats:italic>-tubulin heterodimer formation as the disease mechanism associated to this novel hotspot variant. These results provide new insights into disease mechanisms and offer a foundation for potential future therapeutic approaches aimed at stabilizing <jats:italic>\u03b1<\/jats:italic>\/<jats:italic>\u03b2<\/jats:italic>-tubulin interactions.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fncel.2025.1664953","type":"journal-article","created":{"date-parts":[[2025,9,25]],"date-time":"2025-09-25T11:53:06Z","timestamp":1758801186000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["A mutational hotspot in TUBB2A associated with impaired heterodimer formation and severe brain developmental disorders"],"prefix":"10.3389","volume":"19","author":[{"given":"Gabriele","family":"Di Pasquale","sequence":"first","affiliation":[]},{"given":"Jacopo","family":"Colella","sequence":"additional","affiliation":[]},{"given":"Carola P.","family":"Di Cataldo","sequence":"additional","affiliation":[]},{"given":"Miguel A.","family":"Soler","sequence":"additional","affiliation":[]},{"given":"Sara","family":"Fortuna","sequence":"additional","affiliation":[]},{"given":"Emma","family":"Mizrahi-Powell","sequence":"additional","affiliation":[]},{"given":"Mathilde","family":"Nizon","sequence":"additional","affiliation":[]},{"given":"Benjamin","family":"Cogn\u00e8","sequence":"additional","affiliation":[]},{"given":"Valentina","family":"Turchetti","sequence":"additional","affiliation":[]},{"given":"Giuseppe D.","family":"Mangano","sequence":"additional","affiliation":[]},{"given":"Francesco F.","family":"Comisi","sequence":"additional","affiliation":[]},{"given":"Corrado","family":"Cecchetti","sequence":"additional","affiliation":[]},{"given":"Alessandra","family":"Giliberti","sequence":"additional","affiliation":[]},{"given":"Rosaria","family":"Nardello","sequence":"additional","affiliation":[]},{"given":"Piero","family":"Pavone","sequence":"additional","affiliation":[]},{"given":"Raffaele","family":"Falsaperla","sequence":"additional","affiliation":[]},{"given":"Gabriella","family":"Di Rosa","sequence":"additional","affiliation":[]},{"given":"Gilad D.","family":"Evrony","sequence":"additional","affiliation":[]},{"given":"Maurizio","family":"Delvecchio","sequence":"additional","affiliation":[]},{"given":"Mariasavina","family":"Severino","sequence":"additional","affiliation":[]},{"given":"Andrea","family":"Accogli","sequence":"additional","affiliation":[]},{"given":"Alessandro","family":"Vittori","sequence":"additional","affiliation":[]},{"given":"Vincenzo","family":"Salpietro","sequence":"additional","affiliation":[]}],"member":"1965","published-online":{"date-parts":[[2025,9,25]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"19","DOI":"10.1016\/j.softx.2015.06.001","article-title":"GROMACS: High performance molecular simulations through multi-level parallelism from laptops to supercomputers","volume":"1","author":"Abraham","year":"2015","journal-title":"SoftwareX"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"178","DOI":"10.1111\/cge.12141","article-title":"Polymicrogyria with dysmorphic basal ganglia? Think tubulin!","volume":"85","author":"Amrom","year":"2014","journal-title":"Clin. Genet."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"1676","DOI":"10.1093\/brain\/awu082","article-title":"The wide spectrum of tubulinopathies: what are the key features for the diagnosis?","volume":"137","author":"Bahi-Buisson","year":"2014","journal-title":"Brain"},{"key":"ref4","doi-asserted-by":"publisher","first-page":"129","DOI":"10.1146\/annurev.physchem.51.1.129","article-title":"Generalized born models of macromolecular solvation effects","volume":"51","author":"Bashford","year":"2000","journal-title":"Annu. Rev. Phys. Chem."},{"key":"ref5","doi-asserted-by":"publisher","first-page":"1554","DOI":"10.1016\/j.celrep.2012.11.017","article-title":"Mutations in the \u03b2-tubulin gene TUBB5 cause microcephaly with structural brain abnormalities","volume":"2","author":"Breuss","year":"2012","journal-title":"Cell Rep."},{"key":"ref6","doi-asserted-by":"publisher","first-page":"58","DOI":"10.1016\/j.mcn.2017.03.002","article-title":"Tubulins and brain development - the origins of functional specification","volume":"84","author":"Breuss","year":"2017","journal-title":"Mol. Cell. Neurosci."},{"key":"ref7","doi-asserted-by":"publisher","first-page":"258","DOI":"10.1093\/hmg\/ddw383","article-title":"Uner Tan syndrome caused by a homozygous TUBB2B mutation affecting microtubule stability","volume":"26","author":"Breuss","year":"2017","journal-title":"Hum. Mol. Genet."},{"key":"ref8","doi-asserted-by":"publisher","first-page":"33","DOI":"10.1136\/jmedgenet-2019-106740","article-title":"Defining the phenotypical spectrum associated with variants in TUBB2A","volume":"58","author":"Brock","year":"2021","journal-title":"J. Med. Genet."},{"key":"ref9","doi-asserted-by":"publisher","first-page":"601","DOI":"10.1038\/s10038-020-0739-5","article-title":"Novo mutations of TUBB2A cause infantile-onset epilepsy and developmental delay","volume":"65","author":"Cai","year":"2020","journal-title":"J. Hum. Genet."},{"key":"ref10","doi-asserted-by":"publisher","first-page":"536","DOI":"10.1093\/brain\/aws338","article-title":"Overlapping cortical malformations and mutations in TUBB2B and TUBA1A","volume":"136","author":"Cushion","year":"2013","journal-title":"Brain"},{"key":"ref11","doi-asserted-by":"publisher","first-page":"634","DOI":"10.1016\/j.ajhg.2014.03.009","article-title":"De novo mutations in the beta-tubulin gene TUBB2A cause simplified gyral patterning and infantile-onset epilepsy","volume":"94","author":"Cushion","year":"2014","journal-title":"Am. J. Hum. Genet."},{"key":"ref12","doi-asserted-by":"publisher","first-page":"104932","DOI":"10.1016\/j.ejmg.2024.104932","article-title":"Penetrance, variable expressivity and monogenic neurodevelopmental disorders","volume":"69","author":"de Masfrand","year":"2024","journal-title":"Eur. J. Med. Genet."},{"key":"ref13","doi-asserted-by":"publisher","first-page":"e59744","DOI":"10.1371\/journal.pone.0059744","article-title":"A general and robust ray-casting-based algorithm for triangulating surfaces at the nanoscale","volume":"8","author":"Decherchi","year":"2013","journal-title":"PLoS One"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"1551","DOI":"10.3724\/abbs.2023130","article-title":"Cryo-EM of \u03b1-tubulin isotype-containing microtubules revealed a contracted structure of \u03b14A\/\u03b22A microtubules","volume":"55","author":"Diao","year":"2023","journal-title":"Acta Biochim. Biophys. Sin. Shanghai"},{"key":"ref15","doi-asserted-by":"publisher","first-page":"2725","DOI":"10.1002\/ajmg.a.38352","article-title":"De novo pathogenic variant in TUBB2A presenting with arthrogryposis multiplex congenita, brain abnormalities, and severe developmental delay","volume":"173","author":"Ejaz","year":"2017","journal-title":"Am. J. Med. Genet. A"},{"key":"ref16","doi-asserted-by":"publisher","first-page":"395","DOI":"10.1097\/RMR.0000000000000188","article-title":"Tubulinopathies","volume":"27","author":"Gon\u00e7alves","year":"2018","journal-title":"Top. Magn. Reson. Imaging"},{"key":"ref17","doi-asserted-by":"publisher","first-page":"995","DOI":"10.1038\/ejhg.2012.21","article-title":"Symmetric polymicrogyria and pachygyria associated with TUBB2B gene mutations","volume":"20","author":"Guerrini","year":"2012","journal-title":"Eur. J. Hum. Genet."},{"key":"ref18","doi-asserted-by":"publisher","first-page":"1268013","DOI":"10.3389\/fnmol.2024.1268013","article-title":"Allelic heterogeneity and abnormal vesicle recycling in PLAA-related neurodevelopmental disorders","volume":"17","author":"Iacomino","year":"2024","journal-title":"Front. Mol. Neurosci."},{"key":"ref19","doi-asserted-by":"publisher","first-page":"307","DOI":"10.1038\/s41580-020-0214-3","article-title":"The tubulin code and its role in controlling microtubule properties and functions","volume":"21","author":"Janke","year":"2020","journal-title":"Nat. Rev. Mol. Cell Biol."},{"key":"ref20","doi-asserted-by":"publisher","first-page":"67","DOI":"10.1016\/bs.irn.2023.08.004","article-title":"Involvement of brain metabolism in neurodevelopmental disorders","volume":"173","author":"Kotchetkov","year":"2023","journal-title":"Int. Rev. Neurobiol."},{"key":"ref21","doi-asserted-by":"publisher","first-page":"2817","DOI":"10.1093\/hmg\/ddq182","article-title":"TUBA1A mutations cause wide spectrum lissencephaly (smooth brain) and suggest that multiple neuronal migration pathways converge on alpha tubulins","volume":"19","author":"Kumar","year":"2010","journal-title":"Hum. Mol. Genet."},{"key":"ref22","doi-asserted-by":"publisher","first-page":"1880","DOI":"10.1001\/jama.2014.14604","article-title":"Clinical exome sequencing for genetic identification of rare mendelian disorders","volume":"312","author":"Lee","year":"2014","journal-title":"JAMA"},{"key":"ref23","doi-asserted-by":"publisher","first-page":"1006","DOI":"10.1016\/j.ajhg.2017.10.010","article-title":"Mutations in TUBB4B cause a distinctive sensorineural disease","volume":"101","author":"Luscan","year":"2017","journal-title":"Am. J. Hum. Genet."},{"key":"ref24","doi-asserted-by":"publisher","first-page":"3696","DOI":"10.1021\/acs.jctc.5b00255","article-title":"ff14SB: improving the accuracy of protein side chain and backbone parameters from ff99SB","volume":"11","author":"Maier","year":"2015","journal-title":"J. Chem. Theory Comput."},{"key":"ref25","doi-asserted-by":"publisher","first-page":"87","DOI":"10.1016\/j.semcdb.2022.07.009","article-title":"Tubulin mutations in human neurodevelopmental disorders","volume":"137","author":"Maillard","year":"2023","journal-title":"Semin. Cell Dev. Biol."},{"key":"ref26","doi-asserted-by":"publisher","first-page":"253","DOI":"10.1002\/dneu.22774","article-title":"Tubulin post-translational modifications control neuronal development and functions","volume":"81","author":"Moutin","year":"2021","journal-title":"Dev. Neurobiol."},{"key":"ref27","doi-asserted-by":"publisher","first-page":"5313","DOI":"10.1093\/hmg\/ddv250","article-title":"Recognizable cerebellar dysplasia associated with mutations in multiple tubulin genes","volume":"24","author":"Oegema","year":"2015","journal-title":"Hum. Mol. Genet."},{"key":"ref28","doi-asserted-by":"publisher","first-page":"275","DOI":"10.1146\/annurev-biophys-052118-115325","article-title":"Generalized born implicit solvent models for biomolecules","volume":"48","author":"Onufriev","year":"2019","journal-title":"Annu. Rev. Biophys."},{"key":"ref29","doi-asserted-by":"publisher","first-page":"765992","DOI":"10.3389\/fcell.2021.765992","article-title":"Kinetically stabilizing mutations in Beta tubulins create isotype-specific brain malformations","volume":"9","author":"Park","year":"2021","journal-title":"Front. Cell Dev. Biol."},{"key":"ref30","doi-asserted-by":"publisher","first-page":"a000984","DOI":"10.1101\/mcs.a000984","article-title":"An exome sequencing study of moebius syndrome including atypical cases reveals an individual with CFEOM3A and a TUBB3 mutation","volume":"3","author":"Patel","year":"2017","journal-title":"Cold Spring Harb Mol Case Stud"},{"key":"ref31","doi-asserted-by":"publisher","first-page":"1605","DOI":"10.1002\/jcc.20084","article-title":"UCSF chimera--a visualization system for exploratory research and analysis","volume":"25","author":"Pettersen","year":"2004","journal-title":"J. Comput. Chem."},{"key":"ref32","doi-asserted-by":"publisher","first-page":"W294","DOI":"10.1093\/nar\/gkae255","article-title":"PypKa server: online pKa predictions and biomolecular structure preparation with precomputed data from PDB and AlphaFold DB","volume":"52","author":"Reis","year":"2024","journal-title":"Nucleic Acids Res."},{"key":"ref33","doi-asserted-by":"publisher","first-page":"4442","DOI":"10.1021\/acs.jcim.0c00718","article-title":"PypKa: a flexible Python module for Poisson-Boltzmann-based pKa calculations","volume":"60","author":"Reis","year":"2020","journal-title":"J. Chem. Inf. Model."},{"key":"ref34","doi-asserted-by":"publisher","first-page":"127","DOI":"10.1177\/0883073816672998","article-title":"De novo TUBB2A variant presenting with anterior temporal pachygyria","volume":"32","author":"Rodan","year":"2017","journal-title":"J. Child Neurol."},{"key":"ref35","doi-asserted-by":"publisher","first-page":"744","DOI":"10.1016\/j.ejmg.2018.07.012","article-title":"Tubulin genes and malformations of cortical development","volume":"61","author":"Romaniello","year":"2018","journal-title":"Eur. J. Med. Genet."},{"key":"ref36","doi-asserted-by":"publisher","first-page":"721","DOI":"10.1016\/j.ajhg.2019.02.016","article-title":"Mutations in the neuronal vesicular SNARE VAMP2 affect synaptic membrane fusion and impair human neurodevelopment","volume":"104","author":"Salpietro","year":"2019","journal-title":"Am. J. Hum. Genet."},{"key":"ref37","doi-asserted-by":"publisher","first-page":"412","DOI":"10.2174\/1389202919666180330153316","article-title":"A review of copy number variants in inherited neuropathies","volume":"19","author":"Salpietro","year":"2018","journal-title":"Curr. Genomics"},{"key":"ref38","doi-asserted-by":"publisher","first-page":"33","DOI":"10.1159\/000512160","article-title":"Expanding the phenotype of TUBB2A-related Tubulinopathy: three cases of a novel, heterozygous TUBB2A pathogenic variant p.Gly98Arg","volume":"12","author":"Schmidt","year":"2021","journal-title":"Mol Syndromol"},{"key":"ref39","doi-asserted-by":"publisher","first-page":"2874","DOI":"10.1093\/brain\/awaa174","article-title":"Definitions and classification of malformations of cortical development: practical guidelines","volume":"143","author":"Severino","year":"2020","journal-title":"Brain"},{"key":"ref40","doi-asserted-by":"publisher","first-page":"1892","DOI":"10.1093\/hmg\/ddy096","article-title":"Defective kinesin binding of TUBB2A causes progressive spastic ataxia syndrome resembling sacsinopathy","volume":"27","author":"Sferra","year":"2018","journal-title":"Hum. Mol. Genet."},{"key":"ref41","doi-asserted-by":"publisher","first-page":"844","DOI":"10.1016\/j.str.2011.03.019","article-title":"A smoothed backbone-dependent rotamer library for proteins derived from adaptive kernel density estimates and regressions","volume":"19","author":"Shapovalov","year":"2011","journal-title":"Structure"},{"key":"ref42","doi-asserted-by":"publisher","first-page":"159","DOI":"10.3390\/molecules30010159","article-title":"Bluues_cplx: electrostatics at protein-protein and protein-ligand interfaces","volume":"30","author":"Soler","year":"2025","journal-title":"Molecules"},{"key":"ref43","doi-asserted-by":"publisher","first-page":"367","DOI":"10.1186\/1756-0500-5-367","article-title":"ACPYPE - AnteChamber PYthon parser interfacE","volume":"5","author":"Sousa da Silva","year":"2012","journal-title":"BMC. Res. Notes"},{"key":"ref44","doi-asserted-by":"publisher","first-page":"3803","DOI":"10.1007\/s12035-023-03302-1","article-title":"Insights on the role of \u03b1- and \u03b2-tubulin isotypes in early brain development","volume":"60","author":"Tantry","year":"2023","journal-title":"Mol. Neurobiol."},{"key":"ref45","doi-asserted-by":"publisher","first-page":"2207","DOI":"10.3390\/ijms18102207","article-title":"Tubulin post-translational modifications and microtubule dynamics","volume":"18","author":"Wloga","year":"2017","journal-title":"Int. J. Mol. Sci."},{"key":"ref46","doi-asserted-by":"publisher","first-page":"361","DOI":"10.1016\/j.ejpn.2012.12.006","article-title":"Description of a novel TUBA1A mutation in Arg-390 associated with asymmetrical polymicrogyria and mid-hindbrain dysgenesis","volume":"17","author":"Zanni","year":"2013","journal-title":"Eur. J. Paediatr. Neurol."}],"container-title":["Frontiers in Cellular Neuroscience"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fncel.2025.1664953\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,9,25]],"date-time":"2025-09-25T11:53:07Z","timestamp":1758801187000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fncel.2025.1664953\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,25]]},"references-count":46,"alternative-id":["10.3389\/fncel.2025.1664953"],"URL":"https:\/\/doi.org\/10.3389\/fncel.2025.1664953","relation":{},"ISSN":["1662-5102"],"issn-type":[{"value":"1662-5102","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,9,25]]},"article-number":"1664953"}}