The essential role of CCT2 in the regulation of aggrephagy

Jie Luo1, Ze-Sen Feng1, Ji-Xin Tang1

  • 1Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Diseases of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.

PubMed

Insights

The chaperonin CCT2 acts as an autophagy receptor, selectively targeting aggregated proteins for degradation via aggrephagy. This discovery offers new insights into cellular protein quality control and potential therapeutic strategies for diseases linked to protein aggregation.

Area of Science:

  • Cellular Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Protein aggregation is implicated in various human diseases.
  • Autophagy, specifically aggrephagy, degrades protein aggregates.
  • The selective mechanisms of aggrephagy are not fully understood.

Purpose of the Study:

  • To investigate the role of CCT2 in regulating aggrephagy.
  • To elucidate the mechanism of selective protein aggregate recognition by CCT2.

Main Methods:

  • Mini-review of existing literature on CCT2 and aggrephagy.
  • Analysis of CCT2's function as a molecular chaperone and autophagy receptor.

Main Results:

  • CCT2, a subunit of the TRiC complex, functions as an autophagy receptor.
  • CCT2 selectively targets solid protein aggregates for degradation via an ubiquitination-independent mechanism.
  • CCT2 exhibits a functional switch from chaperone to autophagy receptor.

Conclusions:

  • CCT2 plays a critical role in the selective degradation of protein aggregates.
  • CCT2-mediated aggrephagy offers a novel pathway for cellular protein quality control.
  • Targeting CCT2-mediated aggrephagy may hold therapeutic potential for neurodegenerative diseases.

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