A quantitative dissection of the DNA-binding properties of pathogenic GATA1 mutants

Transcription factors are modulated by a precisely coordinated set of conditions, including cell context, target sequences and their accessibility, and co-factor recruitment. Disruption to any of these conditions can dramatically affect transcription factor activity, but quantitatively characterizing the consequences of individual mutations-either in the transcription factors themselves or in their target sequences-has remained a technical challenge. Zambo et al. present an innovation on their native holdup assay that measures DNA-protein binding activity under physiologic or near-physiologic conditions and use mutant GATA1-ATP2B4 binding as an illustrative example. This technique holds promise for uncovering the molecular mechanisms underlying genetically-driven diseases.