Many-to-one binding by intrinsically disordered protein regions

Area of Science:

• Biochemistry
• Structural Biology
• Molecular Biology

Background:

• Intrinsically disordered proteins (IDPs) and regions (IDRs) lack stable tertiary structures.
• Disordered binding regions (DBRs) within IDPs mediate crucial protein-protein interactions.
• IDPs play vital roles in cellular processes due to their dynamic nature.

Purpose of the Study:

• To investigate the binding mechanisms of multiple DBRs to a single protein partner.
• To characterize the diversity of binding site interactions in many-to-one binding scenarios.
• To understand how IDP flexibility facilitates adaptation to different binding pockets.

Main Methods:

• Collected DBR-protein complexes from the Protein Data Bank.
• Analyzed protein-protein interaction data focusing on many-to-one binding.
• Classified binding profiles into independent and overlapping categories.
• Examined sequence and structural features of DBRs and binding sites.

Main Results:

• Identified two main binding profiles: independent and overlapping.
• Overlapping profiles were further categorized as 'similar' or 'intersecting' binding sites.
• Similar binding sites involved nearly identical residue interactions.
• Intersecting binding sites shared common and divergent interaction residues.
• Demonstrated how IDP flexibility enables adaptation to these distinct binding modes.

Conclusions:

• DBRs exhibit diverse binding strategies to a single protein partner.
• IDP flexibility is key to accommodating varied binding site architectures.
• This adaptability underlies the functional versatility of intrinsically disordered proteins.