A Designed Peptide Targets Two Types of Modifications of p53 with Anti-cancer Activity

Area of Science:

• Biochemistry
• Molecular Biology
• Cancer Research

Background:

• Cancer-related proteins are regulated by multiple post-translational modifications (PTMs), but current therapies target only single PTMs.
• The p53 tumor suppressor is a critical target for cancer therapy, regulated by complex PTMs.
• A novel protein complex, the 'suppresome', was discovered to regulate p53.

Purpose of the Study:

• To investigate the role of Morn3 in mediating composite PTMs on p53.
• To develop a peptide-based strategy targeting Morn3 to simultaneously control multiple PTMs on p53.
• To evaluate the therapeutic potential of targeting composite PTMs for cancer treatment.

Main Methods:

• Identification of Morn3 as a key component of the p53 suppressome.
• Biochemical assays to determine Morn3's recruitment of PTM enzymes (sirtuin deacetylase, ubiquitin ligase).
• In vivo assays and chemico-biological interventions to validate Morn3's function and test the designed peptide (Morncide).

Main Results:

• Morn3 was found to recruit sirtuin deacetylase and ubiquitin ligase, mediating composite PTMs on p53.
• The designed Morn3-targeting peptide, Morncide, successfully activated p53.
• Morncide demonstrated tumor suppression in vivo.

Conclusions:

• Morn3 plays a crucial role in the composite PTM regulation of p53.
• Targeting Morn3 offers a novel strategy for simultaneously modulating multiple PTMs on p53.
• Morncide represents a promising therapeutic candidate for cancer treatment by activating p53 and suppressing tumor growth.