A Binary Bivalent Supramolecular Assembly Platform Based on Cucurbit[8]uril and Dimeric Adapter Protein 14-3-3

Area of Science:

• Biochemistry
• Supramolecular Chemistry
• Structural Biology

Background:

• Protein interactions often rely on multivalent binding events.
• Dimeric 14-3-3 adapter proteins are key in phosphorylation-dependent protein binding.
• Understanding these interactions is crucial for molecular recognition and drug development.

Purpose of the Study:

• To develop a cucurbit[8]uril (Q8)-based supramolecular system for protein assembly.
• To create a binary and bivalent protein assembly platform using Q8 and 14-3-3 proteins.
• To investigate the molecular mechanisms of Q8-induced protein complex formation.

Main Methods:

• Fusion of a phenylalanine-glycine-glycine (FGG) tripeptide motif to an estrogen receptor α (ERα) 14-3-3 binding epitope.
• Utilizing cucurbit[8]uril (Q8) for selective binding and induction of ERα epitope dimerization.
• Analysis of the Q8-induced ternary complex using X-ray crystallography.

Main Results:

• A novel Q8-based supramolecular system was successfully developed.
• Q8-induced dimerization of the ERα epitope enhanced its affinity for 14-3-3 proteins via a binary bivalent binding mode.
• Crystal structure elucidated the intricate supramolecular interactions within the ternary complex.

Conclusions:

• The developed Q8-supramolecular system serves as an effective binary and bivalent protein assembly platform.
• This system offers a novel strategy for modulating protein-protein interactions.
• The findings provide molecular insights into supramolecular binding events involving proteins, peptides, and macrocycles.