Small Heat Shock Proteins Collaborate with FAIM to Prevent Accumulation of Misfolded Protein Aggregates

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Updated: Aug 25, 2025

Coupled Assays for Monitoring Protein Refolding in Saccharomyces cerevisiae
13:52

Coupled Assays for Monitoring Protein Refolding in Saccharomyces cerevisiae

Published on: July 9, 2013

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Hiroaki Kaku1, Allison R Balaj1, Thomas L Rothstein1

  • 1Department of Investigative Medicine, Western Michigan University Homer Stryker M.D. School of Medicine, Kalamazoo, MI 49007, USA.

International Journal of Molecular Sciences
|October 14, 2022
PubMed

Insights

Fas Apoptosis Inhibitory Molecule (FAIM) protects cells from stress by preventing protein aggregation, working alongside small heat shock proteins (sHSPs). This interaction is crucial for mitigating neurodegenerative disease hallmarks like amyloid-beta aggregates.

Area of Science:

  • Cellular stress response
  • Protein aggregation mechanisms
  • Neurodegenerative disease pathology

Background:

  • Environmental insults cause cytotoxic protein aggregation, linked to neurodegenerative diseases.
  • Fas Apoptosis Inhibitory Molecule (FAIM) previously shown to protect cells from stress-induced death by preventing protein aggregation.
  • Small heat shock proteins (sHSPs) also mitigate protein aggregation.

Purpose of the Study:

  • Investigate FAIM protein dynamics during cellular stress.
  • Determine FAIM's role in preventing amyloid-beta (Aβ) aggregate formation, a hallmark of Alzheimer's disease (AD).

Main Methods:

  • Analysis of FAIM protein localization to detergent-insoluble fractions upon cellular stress.
  • Observation of small heat shock protein (sHSP) behavior under stress conditions.
  • In vitro amyloid-beta aggregation assays with FAIM and HSP27.

Main Results:

  • FAIM protein predominantly shifts to the detergent-insoluble fraction following cellular stress.
  • Similar insoluble fraction shifts observed for sHSPs like HSP27.
  • FAIM is recruited to sHSP-containing complexes post-stress.
  • Combined FAIM and HSP27 show enhanced prevention of amyloid-beta aggregation in vitro.

Conclusions:

  • FAIM functions in concert with sHSPs to prevent protein aggregation.
  • FAIM and sHSPs, particularly HSP27, play a synergistic role in inhibiting amyloid-beta aggregation.
  • Findings offer new insights into FAIM-sHSP interactions and their implications for Alzheimer's disease pathogenesis.
Keywords:
fas apoptosis inhibitory molecule (FAIM)protein aggregatessmall heat shock proteins (sHSPs)

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