Evidence for Ca²⁺-induced structural change in diluted GD3 ganglioside dispersions

•GD3 is involved in cancer malignancy and neurodegenerative disorders.•DSC and EPR spectroscopy data indicate that GD3 forms micelles in dilute dispersions.•In presence of Ca2+, GD3 shows athermotropic behavior and a molecular rigidity typical of a lamellar structure.•The Ca2+-induced structural change may be relevant to the GD3 pathophysiological roles.