Targeting the c-Myc coiled coil with interfering peptides

Area of Science:

• Oncology
• Molecular Biology
• Protein-protein Interactions

Background:

• c-Myc is a frequently deregulated oncogene in human cancers.
• Inactivation of Myc can induce tumor regression, presenting a therapeutic opportunity.
• Myc's function relies on dimerization with Max, a key target for intervention.

Purpose of the Study:

• To develop novel interfering peptides targeting the Myc:Max interaction.
• To evaluate the efficacy of these peptides in disrupting Myc function and DNA binding.

Main Methods:

• Applied two strategies: a dominant-negative Max sequence and a peptide (Mip) from a genetic library.
• Fused peptides to acidic extensions to interact with Myc's DNA-binding region.
• Utilized a protein-fragment complementation assay for peptide selection.

Main Results:

• Both Max and Mip peptides effectively outcompeted the Myc:Max interaction.
• Interfering peptides successfully inhibited the DNA binding of the Myc:Max complex.
• Peptides showed increased thermal stability (T(m)) upon interaction with Myc.

Conclusions:

• The developed interfering peptides (Max and Mip) effectively inhibit human Myc:Max activity.
• These peptides are promising tools for analytical and therapeutic research targeting Myc in cancer.