Mapping PTBP2 binding in human brain identifies SYNGAP1 as a target for therapeutic splice switching

Nat Commun. 2023 May 6;14(1):2628. doi: 10.1038/s41467-023-38273-3.

Abstract

Alternative splicing of neuronal genes is controlled partly by the coordinated action of polypyrimidine tract binding proteins (PTBPs). While PTBP1 is ubiquitously expressed, PTBP2 is predominantly neuronal. Here, we define the PTBP2 footprint in the human transcriptome using brain tissue and human induced pluripotent stem cell-derived neurons (iPSC-neurons). We map PTBP2 binding sites, characterize PTBP2-dependent alternative splicing events, and identify novel PTBP2 targets including SYNGAP1, a synaptic gene whose loss-of-function leads to a complex neurodevelopmental disorder. We find that PTBP2 binding to SYNGAP1 mRNA promotes alternative splicing and nonsense-mediated decay, and that antisense oligonucleotides (ASOs) that disrupt PTBP binding redirect splicing and increase SYNGAP1 mRNA and protein expression. In SYNGAP1 haploinsufficient iPSC-neurons generated from two patients, we show that PTBP2-targeting ASOs partially restore SYNGAP1 expression. Our data comprehensively map PTBP2-dependent alternative splicing in human neurons and cerebral cortex, guiding development of novel therapeutic tools to benefit neurodevelopmental disorders.

Publication types

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

MeSH terms

  • Alternative Splicing / genetics
  • Brain / metabolism
  • Heterogeneous-Nuclear Ribonucleoproteins / genetics
  • Heterogeneous-Nuclear Ribonucleoproteins / metabolism
  • Humans
  • Induced Pluripotent Stem Cells* / metabolism
  • Nerve Tissue Proteins* / genetics
  • Nerve Tissue Proteins* / metabolism
  • Polypyrimidine Tract-Binding Protein / genetics
  • Polypyrimidine Tract-Binding Protein / metabolism
  • RNA Splicing
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • ras GTPase-Activating Proteins / genetics

Substances

  • Nerve Tissue Proteins
  • RNA, Messenger
  • SYNGAP1 protein, human
  • ras GTPase-Activating Proteins
  • PTBP1 protein, human
  • Heterogeneous-Nuclear Ribonucleoproteins
  • Polypyrimidine Tract-Binding Protein
  • PTBP2 protein, human