Dry pulverization method overview. Tissue is placed in Covaris tissueTUBES with adapters and attached glass vials (step 1). To keep samples both cold and brittle to facilitate pulverization, tissues are briefly submerged in liquid nitrogen (step 2) between successive rounds of pulverization (step 3). Following the pulverization of samples to a powder, the tissueTUBEs are inverted and tissue powder is collected into attached Covaris glass vials (step 4). Tissue powder is fixed, washed and stored as a pellet at −80°C.