Loss of non-motor kinesin KIF26A causes congenital brain malformations via dysregulated neuronal migration and axonal growth as well as apoptosis

Dev Cell. 2022 Oct 24;57(20):2381-2396.e13. doi: 10.1016/j.devcel.2022.09.011. Epub 2022 Oct 12.

Abstract

Kinesins are canonical molecular motors but can also function as modulators of intracellular signaling. KIF26A, an unconventional kinesin that lacks motor activity, inhibits growth-factor-receptor-bound protein 2 (GRB2)- and focal adhesion kinase (FAK)-dependent signal transduction, but its functions in the brain have not been characterized. We report a patient cohort with biallelic loss-of-function variants in KIF26A, exhibiting a spectrum of congenital brain malformations. In the developing brain, KIF26A is preferentially expressed during early- and mid-gestation in excitatory neurons. Combining mice and human iPSC-derived organoid models, we discovered that loss of KIF26A causes excitatory neuron-specific defects in radial migration, localization, dendritic and axonal growth, and apoptosis, offering a convincing explanation of the disease etiology in patients. Single-cell RNA sequencing in KIF26A knockout organoids revealed transcriptional changes in MAPK, MYC, and E2F pathways. Our findings illustrate the pathogenesis of KIF26A loss-of-function variants and identify the surprising versatility of this non-motor kinesin.

Keywords: apoptosis; cerebral cortex; congenital brain malformation; corpus callosum; development; genetics; kinesin; migration; organoid.

Publication types

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

MeSH terms

  • Animals
  • Apoptosis
  • Brain / metabolism
  • Focal Adhesion Protein-Tyrosine Kinases / metabolism
  • Humans
  • Kinesins* / genetics
  • Mice
  • Neurons* / metabolism

Substances

  • Kinesins
  • Focal Adhesion Protein-Tyrosine Kinases