Genome-wide CRISPR screen reveals v-ATPase as a drug target to lower levels of ALS protein ataxin-2

Cell Rep. 2022 Oct 25;41(4):111508. doi: 10.1016/j.celrep.2022.111508.

Abstract

Mutations in the ataxin-2 gene (ATXN2) cause the neurodegenerative disorders amyotrophic lateral sclerosis (ALS) and spinocerebellar ataxia type 2 (SCA2). A therapeutic strategy using antisense oligonucleotides targeting ATXN2 has entered clinical trial in humans. Additional ways to decrease ataxin-2 levels could lead to cheaper or less invasive therapies and elucidate how ataxin-2 is normally regulated. Here, we perform a genome-wide fluorescence-activated cell sorting (FACS)-based CRISPR-Cas9 screen in human cells and identify genes encoding components of the lysosomal vacuolar ATPase (v-ATPase) as modifiers of endogenous ataxin-2 protein levels. Multiple FDA-approved small molecule v-ATPase inhibitors lower ataxin-2 protein levels in mouse and human neurons, and oral administration of at least one of these drugs-etidronate-is sufficient to decrease ataxin-2 in the brains of mice. Together, we propose v-ATPase as a drug target for ALS and SCA2 and demonstrate the value of FACS-based screens in identifying genetic-and potentially druggable-modifiers of human disease proteins.

Trial registration: ClinicalTrials.gov NCT04494256.

Keywords: ALS; CP: Neuroscience; FACS; SCA2; TDP-43; ataxin-2; bisphosphonate; etidronate; genetic screens; small-molecule therapy; v-ATPase.

Publication types

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

MeSH terms

  • Amyotrophic Lateral Sclerosis* / drug therapy
  • Amyotrophic Lateral Sclerosis* / genetics
  • Amyotrophic Lateral Sclerosis* / metabolism
  • Animals
  • Ataxin-2 / genetics
  • Ataxin-2 / metabolism
  • Etidronic Acid
  • Humans
  • Mice
  • Oligonucleotides, Antisense / genetics
  • Pharmaceutical Preparations
  • Spinocerebellar Ataxias* / drug therapy
  • Spinocerebellar Ataxias* / genetics
  • Vacuolar Proton-Translocating ATPases* / metabolism

Substances

  • Ataxin-2
  • Vacuolar Proton-Translocating ATPases
  • Pharmaceutical Preparations
  • Etidronic Acid
  • Oligonucleotides, Antisense

Associated data

  • ClinicalTrials.gov/NCT04494256