What techniques/analyses do the researchers adopt to test their hypothesis(es)?
The authors employ a range of different methodologies to investigate the different structural conformations of the Q23 and Q78 HTT protein species including cryo electron microscopy (cryoEM), small-angle X-ray scattering (SAXS), deuterium exchange and cross-linking mass spectrometry (MS) analyses. HTT phosphorylation motifs were mapped by MS and then further probed via western blot analyses. Effects of phosphorylation state and polyglutamine tract expansion are then assessed in PRC2 activity assays and immunoprecipitation analysis.