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UBE2O ubiquitinates PTRF/CAVIN1 and inhibits the secretion of exosome-related PTRF/CAVIN1

Xiaotong Cen1,2, Qing Chen1,2, Bin Wang1,2

  • 1Key Laboratory of Biological Targeting Diagnosis, Therapy and Rehabilitation of Guangdong Higher Education Institutes, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510799, China.

Cell Communication and Signaling : CCS
|November 29, 2022
PubMed
Abstract

Insights

Ubiquitin-conjugating enzyme E2O (UBE2O) inhibits exosome secretion and Polymerase I and Transcript Release Factor (PTRF) secretion by ubiquitinating PTRF. This finding offers a potential new strategy for cancer treatment by targeting exosome release.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Cancer Research

Background:

  • Exosomes are key mediators of intercellular communication, playing roles in various physiological and pathological processes.
  • Polymerase I and Transcript Release Factor (PTRF), also known as Caveolin-associated Protein-1 (CAVIN1), is crucial for caveolae formation and exosome secretion.
  • PTRF within exosomes is a potential biomarker for malignancies like glioma and renal cell carcinoma, but its secretion regulation remains unclear.

Discussion:

  • This study elucidates the regulatory mechanism of exosome-related PTRF secretion, identifying UBE2O as a key inhibitor.
  • The interaction between UBE2O, PTRF, and SDPR (CAVIN2) highlights a complex regulatory network influencing exosome biogenesis and release.
  • Understanding these molecular interactions provides insights into exosome pathway dysregulation in cancer.

Key Insights:

  • Ubiquitin-conjugating enzyme E2O (UBE2O) directly interacts with and ubiquitinates PTRF, inhibiting PTRF's role in exosome secretion.
  • UBE2O decreases overall exosome secretion and consequently downregulates the secretion of PTRF within exosomes.
  • Serum Deprivation Protein Response (SDPR) promotes PTRF expression in exosomes, yet UBE2O's inhibitory effect on PTRF secretion persists.

Outlook:

  • Targeting UBE2O to modulate exosome release and PTRF secretion presents a novel therapeutic strategy for cancers where PTRF is a biomarker.
  • Further research into the UBE2O-SDPR-PTRF axis could uncover additional therapeutic targets for cancer treatment.
  • Investigating the precise role of UBE2O in other cancer types and its therapeutic potential warrants further exploration.
Keywords:
Exosome secretionPTRF/CAVIN1SDPR/CAVIN2UBE2OUbiquitination

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