Low-Input MNase Accessibility of Chromatin (Low-Input MACC)

An understanding of the dynamic structural properties of chromatin requires techniques that allow the profiling of regions of both open and closed chromatin as well as the assessment of nucleosome occupancy. The recently developed MNase accessibility (MACC) technique allows for the simultaneous measurement of chromatin opening and compaction, as well as nucleosome occupancy, on a genome-wide scale in a single assay. This article presents a low-input MACC procedure that considerably extends the utility of the original MACC assay. Low-input MACC generates high-quality data using very low cell numbers (as few as 50 cells per titration point), making it ideal for samples obtained after fluorescence-activated cell sorting or dissection, or in clinical settings. Moreover, low-input MACC has significantly improved several steps of the initial method, offering a more rapid and robust methodology. © 2019 by John Wiley & Sons, Inc.