Decoding the Post-translational Modification Crosstalk: Functional Implications of Phosphorylation, Acetylation, and...

Area of Science:

• Biochemistry
• Proteomics
• Molecular Biology

Background:

• Post-translational modifications (PTMs) significantly expand proteome function by altering protein structure and interactions.
• Understanding the physicochemical impact of PTMs on protein hydropathy is crucial but remains mechanistically limited.

Purpose of the Study:

• To quantitatively evaluate PTM-induced physicochemical changes using an extended hydropathy scale.
• To determine the effect and magnitude of hydropathy shifts at modification sites.

Main Methods:

• Extension of the Protocol for Assigning a Residue's Character on a Hydropathy (PARCH) scale.
• Systematic evaluation of PTM-induced physicochemical changes.
• Quantification of hydropathy shifts and mapping of local protein environment perturbations.

Main Results:

• Phosphorylation consistently increases hydropathy (hydrophilicity) due to the charged phosphate group.
• N-lysine acetylation shows context-dependent hydropathy effects, often increasing hydrophobicity.
• Methylation exhibits complex, non-uniform hydropathy signatures, with potential for increased water exposure.

Conclusions:

• The PARCH scale provides a quantitative tool to decipher PTM-induced hydropathy landscape changes.
• This offers a predictive foundation for understanding PTMs' structural, hydropathy, and functional consequences.