Peptidic transition state analogues as PRMT inhibitors

Area of Science:

• Biochemistry
• Enzymology
• Drug Discovery

Background:

• Protein arginine N-methyltransferases (PRMTs) are crucial enzymes utilizing S-adenosyl-l-methionine (AdoMet) for protein methylation.
• PRMTs are implicated in various physiological and pathological processes, making them attractive therapeutic targets.
• Developing specific PRMT inhibitors is challenging due to conserved active sites across the nine PRMT family members.

Purpose of the Study:

• To extend a methodology for creating peptide-based transition state mimicking inhibitors of PRMTs.
• To synthesize and evaluate histone H4 tail peptide-based inhibitors targeting arginine residues.

Main Methods:

• A novel approach covalently links an adenosine moiety (mimicking AdoMet) to arginine residues within substrate-derived peptides.
• Histone H4 tail peptides with adenosine linked to Arg3 were synthesized.
• Inhibition assays were performed using PRMT1 and PRMT6.

Main Results:

• The synthesized histone H4-based transition state mimics demonstrated low micromolar IC50 values against PRMT1 and PRMT6.
• This indicates successful application of the methodology to generate effective PRMT inhibitors.
• The approach shows potential for broader application across the PRMT family.

Conclusions:

• The developed methodology is effective for creating peptide-based transition state mimics for PRMT inhibition.
• These inhibitors show potent activity against specific PRMTs, offering a path towards selective targeting.
• This work advances the development of PRMT-targeted therapeutics by addressing specificity challenges.