Murine knockin model for progranulin-deficient frontotemporal dementia with nonsense-mediated mRNA decay

Proc Natl Acad Sci U S A. 2018 Mar 20;115(12):E2849-E2858. doi: 10.1073/pnas.1722344115. Epub 2018 Mar 6.


Frontotemporal dementia (FTD) is the most common neurodegenerative disorder in individuals under age 60 and has no treatment or cure. Because many cases of FTD result from GRN nonsense mutations, an animal model for this type of mutation is highly desirable for understanding pathogenesis and testing therapies. Here, we generated and characterized GrnR493X knockin mice, which model the most common human GRN mutation, a premature stop codon at arginine 493 (R493X). Homozygous GrnR493X mice have markedly reduced Grn mRNA levels, lack detectable progranulin protein, and phenocopy Grn knockout mice, with CNS microgliosis, cytoplasmic TDP-43 accumulation, reduced synaptic density, lipofuscinosis, hyperinflammatory macrophages, excessive grooming behavior, and reduced survival. Inhibition of nonsense-mediated mRNA decay (NMD) by genetic, pharmacological, or antisense oligonucleotide-based approaches showed that NMD contributes to the reduced mRNA levels in GrnR493X mice and cell lines and in fibroblasts from patients containing the GRNR493X mutation. Moreover, the expressed truncated R493X mutant protein was functional in several assays in progranulin-deficient cells. Together, these findings establish a murine model for in vivo testing of NMD inhibition or other therapies as potential approaches for treating progranulin deficiency caused by the R493X mutation.

Keywords: frontotemporal dementia; lysosome; neurodegeneration; nonsense-mediated mRNA decay; progranulin.

Publication types

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

MeSH terms

  • Animals
  • Disease Models, Animal
  • Fibroblasts / drug effects
  • Frontotemporal Dementia / etiology*
  • Frontotemporal Dementia / genetics
  • Gene Knock-In Techniques
  • Granulins
  • Humans
  • Intercellular Signaling Peptides and Proteins / genetics*
  • Intercellular Signaling Peptides and Proteins / metabolism
  • Lysosomes / genetics
  • Lysosomes / metabolism
  • Mice, Inbred C57BL
  • Mutation*
  • Nonsense Mediated mRNA Decay / drug effects*
  • Oligonucleotides, Antisense / pharmacology
  • Progranulins
  • RNA, Messenger


  • GRN protein, human
  • Granulins
  • Grn protein, mouse
  • Intercellular Signaling Peptides and Proteins
  • Oligonucleotides, Antisense
  • Progranulins
  • RNA, Messenger