Crystallization and preliminary crystallographic studies of a SAM domain at the C-terminus of human p73α

p73 is a recently discovered homologue of the tumour suppressor p53 and contains all three functional domains of p53. The α-splice variant of p73 (p73α) contains an additional structural domain near its C-­terminus that has sequence homology with the sterile α-motif (SAM) domain. This domain is considered to be responsible for mediating protein–protein interactions. Pyramidal crystals of human p73α SAM domain were obtained by the hanging-drop vapour-diffusion method with ammonium dihydrogen orthophosphate as the precipitant. The crystals diffract to 2.54 Å resolution and belong to the tetragonal space group P4₁2₁2, with unit-cell parameters a = b = 32.02, c = 133.84 Å. The structure was solved by molecular replacement using the NMR structure of the same protein as the search model.