STXBP1 encephalopathies: Clinical spectrum, disease mechanisms, and therapeutic strategies

J Neurochem. 2021 Apr;157(2):165-178. doi: 10.1111/jnc.15120. Epub 2020 Aug 4.

Abstract

Mutations in Munc18-1/STXBP1 (syntaxin-binding protein 1) are linked to various severe early epileptic encephalopathies and neurodevelopmental disorders. Heterozygous mutations in the STXBP1 gene include missense, nonsense, frameshift, and splice site mutations, as well as intragenic deletions and duplications and whole-gene deletions. No genotype-phenotype correlation has been identified so far, and patients are treated by anti-epileptic drugs because of the lack of a specific disease-modifying therapy. The molecular disease mechanisms underlying STXBP1-linked disorders are yet to be fully understood, but both haploinsufficiency and dominant-negative mechanisms have been proposed. This review focuses on the current understanding of the phenotypic spectrum of STXBP1-linked disorders, as well as discusses disease mechanisms in the context of the numerous pathways in which STXBP1 functions in the brain. We additionally evaluate the available animal models to study these disorders and highlight potential therapeutic approaches for treating these devastating diseases.

Keywords: Munc18-1; STXBP1; encephalopathy; epilepsy; synapse; therapeutic approaches.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Anticonvulsants / therapeutic use*
  • Brain / metabolism
  • Brain Diseases / genetics
  • Brain Diseases / metabolism*
  • Humans
  • Munc18 Proteins / genetics
  • Munc18 Proteins / metabolism*
  • Mutation / genetics
  • Neurodevelopmental Disorders / drug therapy*
  • Neurodevelopmental Disorders / genetics

Substances

  • Anticonvulsants
  • Munc18 Proteins
  • STXBP1 protein, human