1. Academic Validation
  2. Biallelic loss of human CTNNA2, encoding αN-catenin, leads to ARP2/3 complex overactivity and disordered cortical neuronal migration

Biallelic loss of human CTNNA2, encoding αN-catenin, leads to ARP2/3 complex overactivity and disordered cortical neuronal migration

  • Nat Genet. 2018 Aug;50(8):1093-1101. doi: 10.1038/s41588-018-0166-0.
Ashleigh E Schaffer 1 2 Martin W Breuss 3 Ahmet Okay Caglayan 4 5 Nouriya Al-Sanaa 6 Hind Y Al-Abdulwahed 6 Hande Kaymakçalan 7 Cahide Yılmaz 8 Maha S Zaki 9 Rasim O Rosti 3 Brett Copeland 3 Seung Tae Baek 3 Damir Musaev 3 Eric C Scott 3 Tawfeg Ben-Omran 10 Ariana Kariminejad 11 Hulya Kayserili 12 Faezeh Mojahedi 13 Majdi Kara 14 Na Cai 3 Jennifer L Silhavy 3 Seham Elsharif 14 Elif Fenercioglu 15 Bruce A Barshop 16 Bulent Kara 17 Rengang Wang 3 Valentina Stanley 3 Kiely N James 3 Rahul Nachnani 3 Aneesha Kalur 18 Hisham Megahed 9 Faruk Incecik 19 Sumita Danda 20 Yasemin Alanay 21 Eissa Faqeih 22 Gia Melikishvili 23 Lobna Mansour 24 Ian Miller 25 Biayna Sukhudyan 26 Jamel Chelly 27 William B Dobyns 28 Kaya Bilguvar 4 Rami Abou Jamra 29 Murat Gunel 4 Joseph G Gleeson 30
Affiliations

Affiliations

  • 1 Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA. [email protected].
  • 2 Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA. [email protected].
  • 3 Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA.
  • 4 Departments of Neurosurgery, Neurobiology, and Genetics, Yale University School of Medicine, New Haven, CT, USA.
  • 5 Department of Medical Genetics, Istanbul Bilim University, Istanbul, Turkey.
  • 6 Department of Pediatrics, Johns Hopkins Aramco Healthcare, Dhahran, Saudi Arabia.
  • 7 Department of Pediatrics, Istanbul Bilim University, Istanbul, Turkey.
  • 8 Department of Pediatrics, Yıldırım Beyazıt University, Ankara, Turkey.
  • 9 Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt.
  • 10 Clinical and Metabolic Genetics Section, Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar.
  • 11 Kariminejad-Najmabadi Pathology and Genetic Center, Tehran, Iran.
  • 12 Department of Medical Genetics, Koç University School of Medicine, Istanbul, Turkey.
  • 13 Mashhad Medical Genetic Counseling Center, Mashhad, Iran.
  • 14 University of Tripoli, Tripoli Children's Hospital, Tripoli, Libya.
  • 15 L.E.S. Mikrogen Genetic Diseases Diagnosis Center, Istanbul, Turkey.
  • 16 Department of Pediatrics, Biochemical Genetics Program, University of California, San Diego, San Diego, CA, USA.
  • 17 Department of Pediatric Neurology, Kocaeli University, Kocaeli, Turkey.
  • 18 Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA.
  • 19 Department of Pediatric Neurology, Cukurova University, Adana, Turkey.
  • 20 Department of Clinical Genetics, Christian Medical College and Hospital, Vellore, India.
  • 21 Pediatric Genetics Unit, Department of Pediatrics, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey.
  • 22 Section of Medical Genetics, Department of Pediatrics, King Fahad Medical City, Children's Hospital, Riyadh, Saudi Arabia.
  • 23 Department of Pediatrics, MediClubGeorgia, Tbilisi, Georgia.
  • 24 Pediatric Department, Neuropediatric Unit, Cairo University Children's Hospital, Cairo, Egypt.
  • 25 Neurology Department, Nicklaus Children's Hospital, Miami, FL, USA.
  • 26 Arabkir Joint Medical Center and Institute of Child and Adolescent Health, Yerevan, Armenia.
  • 27 Institut Cochin, Université Paris-Descartes, CNRS (UMR 8104), Paris, France.
  • 28 Departments of Pediatrics and Neurology, University of Washington, Seattle, WA, USA.
  • 29 Institute of Human Genetics, University of Leipzig Hospitals and Clinics, Leipzig, Germany.
  • 30 Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA. [email protected].
Abstract

Neuronal migration defects, including pachygyria, are among the most severe developmental brain defects in humans. Here, we identify biallelic truncating mutations in CTNNA2, encoding αN-catenin, in patients with a distinct recessive form of pachygyria. CTNNA2 was expressed in human cerebral cortex, and its loss in neurons led to defects in neurite stability and migration. The αN-catenin paralog, αE-catenin, acts as a switch regulating the balance between β-catenin and Arp2/3 actin filament activities1. Loss of αN-catenin did not affect β-catenin signaling, but recombinant αN-catenin interacted with purified actin and repressed ARP2/3 actin-branching activity. The actin-binding domain of αN-catenin or ARP2/3 inhibitors rescued the neuronal phenotype associated with CTNNA2 loss, suggesting ARP2/3 de-repression as a potential disease mechanism. Our findings identify CTNNA2 as the first catenin family member with biallelic mutations in humans, causing a new pachygyria syndrome linked to actin regulation, and uncover a key factor involved in ARP2/3 repression in neurons.

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