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


Schaffer A. E. , Breuss M. W. , Caglayan A. O. , Al-Sanaa N., Al-Abdulwahed H. Y. , Kaymakcalan H., et al.

NATURE GENETICS, cilt.50, ss.1093-1107, 2018 (SCI İndekslerine Giren Dergi)

  • Cilt numarası: 50 Konu: 8
  • Basım Tarihi: 2018
  • Doi Numarası: 10.1038/s41588-018-0166-0
  • Dergi Adı: NATURE GENETICS
  • Sayfa Sayısı: ss.1093-1107

Özet

Neuronal migration defects, including pachygyria, are among the most severe developmental brain defects in humans. Here, we identify biallelic truncating mutations in CTNNA2, encoding alpha N-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 alpha N-catenin paralog, alpha E-catenin, acts as a switch regulating the balance between beta-catenin and Arp2/3 actin filament activities(1). Loss of alpha N-catenin did not affect beta-catenin signaling, but recombinant alpha N-catenin interacted with purified actin and repressed ARP2/3 actin-branching activity. The actin-binding domain of alpha N-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.