Seeking allosteric networks in PDZ domains

Area of Science:

• Biochemistry
• Structural Biology
• Computational Biology

Background:

• Postsynaptic density-95/Discs large/Zonula occludens 1 (PDZ) domains are a model system for studying single-domain protein allostery.
• Decades of research have yielded contradictory results regarding the existence and location of allosteric networks within PDZ domains.

Purpose of the Study:

• To review theoretical and experimental approaches used to investigate allosteric networks in PDZ domains.
• To compare proposed allosteric networks in two specific PDZ domains: PSD-95 (third domain) and PTP-BL (second domain).

Main Methods:

• Statistical correlation analysis of amino acid residue covariation.
• Theoretical modeling and experimental techniques to probe energetic networks.
• Comparative analysis of allosteric network models.

Main Results:

• Different methodologies provide conflicting data on the structural localization of allosteric networks in PDZ domains.
• Contradictions exist between proposed allosteric networks for PSD-95 and PTP-BL PDZ domains.
• The existence of allosteric networks in PDZ domains has been questioned by some studies.

Conclusions:

• Significant discrepancies exist between various methods used to study allostery in PDZ domains.
• Further research is required to resolve the contradictions and fully understand allosteric mechanisms in PDZ domains.