Much Anticipated—The Bioactive Conformation of Epothilone and Its Binding to Tubulin

Filled pockets: Epothilones initiate apoptosis in eukaryotic cells by inducing extensive polymerization of αβ-tubulin. Until recently, little was known about the binding mode of epothilones within the tubulin binding cavity. The structure of the epothilone A/tubulin complex (see picture) determined by electron crystallography has dramatically reversed the situation.