How Abl ‘shape-shifts’ in drug-resistant CML

In analyzing the structure of these allosteric mutants, Dr Kalodimos and his colleagues discovered the mutants altered Abl’s shape to activate it and did not interfere with how imatinib plugs into the kinase domain.

This finding points the way to new treatments to overcome such resistance, according to Dr Kalodimos.

“There is now a new generation of drugs that bind to the allosteric pocket to inhibit its activity,” he said. “These could be combined with [imatinib] to overcome allosteric mutations to shift Abl into an inhibited state.”

Dr Kalodimos said that treatment strategy could also be applied to other forms of leukemia that have uncontrolled Bcr-Abl activity. And this new basic understanding of Abl regulation will yield insight into similar enzymes in which allosteric regulation controls a kinase domain.