Synaptic Dysfunction in Human Neurons With Autism-Associated Deletions in PTCHD1-AS

P Joel Ross; Wen-Bo Zhang; Rebecca S F Mok; Kirill Zaslavsky; Eric Deneault; Lia D'Abate; Deivid C Rodrigues; Ryan K C Yuen; Muhammad Faheem; Marat Mufteev; Alina Piekna; Wei Wei; Peter Pasceri; Rebecca J Landa; Andras Nagy; Balazs Varga; Michael W Salter; Stephen W Scherer; James Ellis

doi:10.1016/j.biopsych.2019.07.014

Synaptic Dysfunction in Human Neurons With Autism-Associated Deletions in PTCHD1-AS

Biol Psychiatry. 2020 Jan 15;87(2):139-149. doi: 10.1016/j.biopsych.2019.07.014. Epub 2019 Jul 29.

Authors

P Joel Ross¹, Wen-Bo Zhang², Rebecca S F Mok³, Kirill Zaslavsky³, Eric Deneault⁴, Lia D'Abate⁵, Deivid C Rodrigues¹, Ryan K C Yuen⁵, Muhammad Faheem⁴, Marat Mufteev³, Alina Piekna¹, Wei Wei¹, Peter Pasceri¹, Rebecca J Landa⁶, Andras Nagy⁷, Balazs Varga⁸, Michael W Salter⁹, Stephen W Scherer¹⁰, James Ellis¹¹

Affiliations

¹ Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada.
² Neurosciences and Mental Health Program, The Hospital for Sick Children, Toronto, Ontario, Canada.
³ Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
⁴ Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada; The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Ontario, Canada.
⁵ Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada; The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
⁶ Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, Maryland; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.
⁷ Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada; Lunenfeld-Tenenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
⁸ Lunenfeld-Tenenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
⁹ Neurosciences and Mental Health Program, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Physiology, University of Toronto, Toronto, Ontario, Canada.
¹⁰ Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada; The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada; McLaughlin Centre, University of Toronto, Toronto, Ontario, Canada.
¹¹ Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada. Electronic address: jellis@sickkids.ca.

Abstract

Background: The Xp22.11 locus that encompasses PTCHD1, DDX53, and the long noncoding RNA PTCHD1-AS is frequently disrupted in male subjects with autism spectrum disorder (ASD), but the functional consequences of these genetic risk factors for ASD are unknown.

Methods: To evaluate the functional consequences of PTCHD1 locus deletions, we generated induced pluripotent stem cells (iPSCs) from unaffected control subjects and 3 subjects with ASD with microdeletions affecting PTCHD1-AS/PTCHD1, PTCHD1-AS/DDX53, or PTCHD1-AS alone. Function of iPSC-derived cortical neurons was assessed using molecular approaches and electrophysiology. We also compiled novel and known genetic variants of the PTCHD1 locus to explore the roles of PTCHD1 and PTCHD1-AS in genetic risk for ASD and other neurodevelopmental disorders. Finally, genome editing was used to explore the functional consequences of deleting a single conserved exon of PTCHD1-AS.

Results: iPSC-derived neurons from subjects with ASD exhibited reduced miniature excitatory postsynaptic current frequency and N-methyl-D-aspartate receptor hypofunction. We found that 35 ASD-associated deletions mapping to the PTCHD1 locus disrupted exons of PTCHD1-AS. We also found a novel ASD-associated deletion of PTCHD1-AS exon 3 and showed that exon 3 loss altered PTCHD1-AS splicing without affecting expression of the neighboring PTCHD1 coding gene. Finally, targeted disruption of PTCHD1-AS exon 3 recapitulated diminished miniature excitatory postsynaptic current frequency, supporting a role for the long noncoding RNA in the etiology of ASD.

Conclusions: Our genetic findings provide strong evidence that PTCHD1-AS deletions are risk factors for ASD, and human iPSC-derived neurons implicate these deletions in the neurophysiology of excitatory synapses and in ASD-associated synaptic impairment.

Keywords: Autism spectrum disorder; Excitatory synapses; Genetics; Induced pluripotent stem cells; Long noncoding RNA; Neurons.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Autism Spectrum Disorder* / genetics
Autistic Disorder* / genetics
Humans
Induced Pluripotent Stem Cells*
Male
Membrane Proteins
Neurons
Synapses

Substances

Membrane Proteins
PTCHD1 protein, human

Abstract

Publication types

MeSH terms

Substances

Grants and funding