Zebrafish models of candidate human epilepsy-associated genes provide evidence of hyperexcitability
Christopher Mark LaCoursiere,
Jeremy F.P. Ullmann,
Hyun Yong Koh,
Laura Turner,
Cristina M. Baker,
Barbara Robens,
Wanqing Shao,
Alexander Rotenberg,
Christopher M. McGraw,
Annapurna H. Poduri
Affiliations
Christopher Mark LaCoursiere
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
Jeremy F.P. Ullmann
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
Hyun Yong Koh
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Departments of Neuroscience and Pediatrics, Division of Neurology and Developmental Neuroscience, BCM, Houston, TX 77030, USA
Laura Turner
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
Cristina M. Baker
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, 7034 Trondheim, Norway
Barbara Robens
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
Wanqing Shao
Research Computing, Department of Information Technology, Boston Children’s Hospital, Boston, MA 02115, USA
Alexander Rotenberg
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, Boston, MA 02115, USA; Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
Christopher M. McGraw
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, Boston, MA 02115, USA; Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
Annapurna H. Poduri
F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, Boston, MA 02115, USA; Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Corresponding author
Summary: Hundreds of novel candidate human epilepsy-associated genes have been identified thanks to advancements in next-generation sequencing and large genome-wide association studies, but establishing genetic etiology requires functional validation. We generated a list of >2,200 candidate epilepsy-associated genes, of which 48 were developed into stable loss-of-function (LOF) zebrafish models. Of those 48, evidence of seizure-like behavior was present in 5 (arfgef1, kcnd2, kcnv1, ubr5, and wnt8b). Further characterization provided evidence for epileptiform activity via electrophysiology in kcnd2 and wnt8b mutants. Additionally, arfgef1 and wnt8b mutants showed a decrease in the number of inhibitory interneurons in the optic tectum of larval animals. Further, RNA sequencing (RNA-seq) revealed convergent transcriptional abnormalities between mutant lines, consistent with their developmental defects and hyperexcitable phenotypes. These zebrafish models provide strongest experimental evidence supporting the role of ARFGEF1, KCND2, and WNT8B in human epilepsy and further demonstrate the utility of this model system for evaluating candidate human epilepsy genes.
