The Relationship Between Protein Interactions and PTMs

Proteins are the main executors of cellular activities, and their function relies on their precise spatial structure and regulation. Proteins regulate their functions mainly through interactions and post-translational modifications.

 

Protein Interaction

Protein interaction refers to the stable or temporary structures formed between protein molecules through non-covalent bonds (such as electrostatic forces, hydrogen bonds, Van der Waals forces, etc.). These interactions are vital to the structure, stability, function, and regulation of proteins. For example, the secondary structure of proteins (α-helix and β-sheet) is maintained by hydrogen bonds; while the tertiary and quaternary structures of proteins are maintained by various non-covalent bonds. Additionally, protein complexes formed through protein-protein interactions can perform various biological functions.

 

Post-Translational Modification

Post-translational modification refers to a series of enzymatic reactions that chemically modify proteins after their synthesis, such as phosphorylation, acetylation, ubiquitination, etc. Post-translational modifications can change the charge, shape, stability, affinity, and other physicochemical properties of proteins, thereby affecting their function and activity.

 

The Relationship Between Protein Interaction and Post-Translational Modification

Protein interaction and post-translational modification influence each other and jointly regulate the function of proteins. On the one hand, post-translational modifications can change the structure of proteins, affecting protein-protein interactions. For instance, phosphorylation can introduce a negative charge, alter the charge distribution of proteins, and affect the structure of proteins and their interactions with other proteins. On the other hand, protein-protein interactions can also affect post-translational modifications of proteins. For example, the activity of certain enzymes requires the formation of complexes with other proteins to catalyze post-translational modifications of proteins.

 

Protein interaction and post-translational modification are two crucial steps in the regulation of protein function. Their mutual influence and interaction are significant for understanding life activities.