Inter-lobe Motions Allosterically Regulate the Structure and Function of EGFR Kinase

Area of Science:

• Biochemistry
• Structural Biology
• Molecular Biology

Background:

• Protein kinases are crucial for cellular signaling and are key targets in drug discovery.
• Epidermal growth factor receptor (EGFR) kinase is a well-studied receptor tyrosine kinase involved in cancer and dimerization-driven activation.

Purpose of the Study:

• To analyze EGFR kinase crystal structures and molecular dynamics to understand the determinants of its structural configurations.
• To elucidate the relationship between inter-lobe arrangement, intermolecular interactions, and kinase activity.

Main Methods:

• Analysis of 206 available crystal structures of the EGFR kinase domain.
• Examination of molecular dynamics simulations to observe kinase behavior.
• Correlation of structural data with intermolecular interactions and crystal packing.

Main Results:

• The N- and C-terminal lobe arrangement critically regulates EGFR kinase structure, responding sensitively to intermolecular interactions and the crystal environment.
• A wide range of crystal forms correlates with diverse inter-lobe arrangements.
• Catalytically important motifs and bound ATP configurations are tightly linked to inter-lobe motion.
• Activating asymmetric dimer interactions promote an open-lobe arrangement, leading to a catalytically active state.

Conclusions:

• Intermolecular interactions and crystal environment are primary determinants of EGFR kinase structural states.
• The inter-lobe arrangement is a key regulator of EGFR kinase activity, enabling a catalytically active conformation upon dimerization.