Interplay of self-association and conformational flexibility in regulating protein function

Area of Science:

• Biochemistry
• Structural Biology
• Molecular Biology

Background:

• Homodimers are the most common protein self-association form, crucial for regulating enzymes, ion channels, transporters, and transcription factors.
• Conformational flexibility is increasingly recognized as a key regulator of homodimer function.

Purpose of the Study:

• To review and synthesize findings on the role of conformational flexibility in regulating homodimer function.
• To explore how protein self-association influences ligand binding and biological activity.

Main Methods:

• Review of existing literature and experimental findings.
• Analysis of protein structural dynamics and allosteric mechanisms.

Main Results:

• Intertwined homodimers exhibit significant conformational flexibility, enabling domain motion and regulation of subunit interfaces.
• This flexibility allows proteins to modulate recognition surfaces, impacting function across related family members.
• Homodimer formation can prime proteins by inducing mobility at ligand-binding sites, potentially via allosteric mechanisms.
• Induced mobility likely enhances ligand binding through conformational selection.

Conclusions:

• Conformational flexibility is a critical determinant of homodimer function, impacting protein-protein and protein-ligand interactions.
• Protein self-association itself can act as an allosteric regulator, pre-organizing proteins for function.
• Understanding these dynamics offers new insights into molecular machines and allosteric regulation.