Expression, purification, crystallization and X-ray data collection for RAS and its mutants

This article expands on crystal structure data for human H-RAS with mutations at position Y137, briefly described in a paper on the effects of phosphorylation of Y137 by ABL kinases (Tyrosine phosphorylation of RAS by ABL allosterically enhances effector binding, published in the FASEB Journal [1]). The crystal structures of the Y137E mutant (phosphorylation mimic) and of the Y137F mutant (without the hydroxyl group where phosphorylation occurs) were deposited in the Protein Data Bank with PDB codes 4XVQ (H-RASY137E) and 4XVR (H-RASY137F). This article includes details for expression and purification of RAS and its mutants with no affinity tags, in vitro exchange of guanine nucleotides, protein crystallization, X-ray data collection and structure refinement.