RPS23RG1 Is Required for Synaptic Integrity and Rescues Alzheimer's Disease-Associated Cognitive Deficits

Biol Psychiatry. 2019 Aug 1;86(3):171-184. doi: 10.1016/j.biopsych.2018.08.009. Epub 2018 Aug 25.


Background: Although synaptic impairment is a prerequisite to cognitive deficiencies in Alzheimer's disease (AD), mechanisms underlying the dysregulation of essential synaptic scaffolding components and their integrity remain elusive. RPS23RG1 is a newly identified protein implicated in AD. However, the physiological function of RPS23RG1 has yet to be determined.

Methods: We investigated the role of RPS23RG1 in maintaining synaptic structure and function in cell cultures and in Rps23rg1 knockout mice and determined whether targeting RPS23RG1-mediated pathways has therapeutic potential in APP/PS1 AD model mice.

Results: Deletion of the Rps23rg1 gene resulted in severe memory deficits and impairment of postsynaptic structure and function, with marked reductions in postsynaptic densities-93 and -95 (PSD-93 and PSD-95) levels. RPS23RG1 interacted with PSD-93/PSD-95 through its intracellular domain, consequently sequestering PSD-93/PSD-95 from murine double minute 2-mediated ubiquitination and degradation, thereby maintaining synaptic function. Restoration of PSD-93/PS-D95 levels reversed synaptic and memory deficits in Rps23rg1 knockout mice. We further observed attenuated RPS23RG1 expression in human AD, which positively correlated with PSD-93/PSD-95 levels. Importantly, an RPS23RG1-derived peptide comprising a unique PSD-93/PSD-95 interaction motif rescued synaptic and cognitive defects in Rps23rg1 knockout and AD mouse models.

Conclusions: Our results reveal a role for RPS23RG1 in maintaining synaptic integrity and function and provide a new mechanism for synaptic dysfunction in AD pathogenesis. This demonstrates that RPS23RG1-mediated pathways show good therapeutic potential in AD intervention.

Keywords: Alzheimer’s disease; PSD-93; PSD-95; RPS23RG1; Synaptic plasticity; Ubiquitination.

Publication types

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

MeSH terms

  • Alzheimer Disease / genetics
  • Alzheimer Disease / metabolism
  • Alzheimer Disease / physiopathology
  • Animals
  • Cognitive Dysfunction / genetics
  • Cognitive Dysfunction / metabolism*
  • Cognitive Dysfunction / physiopathology
  • Disease Models, Animal
  • Disks Large Homolog 4 Protein / metabolism*
  • Gene Expression Regulation
  • Gene Knockdown Techniques
  • Hippocampus / metabolism
  • Humans
  • Maze Learning
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Neuronal Plasticity*
  • Ribosomal Proteins / genetics
  • Ribosomal Proteins / metabolism*


  • Disks Large Homolog 4 Protein
  • RPS23 protein, human
  • RPS23R1 protein, mouse
  • Ribosomal Proteins