Previously, I purified the HTT N-HEAT_81-1643 domain and showed that the HTT N-HEAT_81-1643 domain also elutes early from a Superose 6 column 10/300 (https://zenodo.org/record/3462496#.XY4limYpA2x). One hypothesis we proposed that could explain the early elution volume is that the construct HTT N-HEAT_81-1643 forms a complex with nucleic acid material. Here we added an additional purification step with heparin resin to remove nucleic acid material from the sample. This strategy was successful for full length HTT+HAP40 samples in removing nucleic acid and other impurities from the samples (https://zenodo.org/record/2628064#.XYTL7WYpDcs) (performed by Dr. Rachel Harding). Purified HTT N-HEAT_81-1643 domain sample was used to perform a buffer screen and biophysical characterization with DSLS, DSF and DLS.

Dr. Harding is the recipient of the Huntington's Disease Society of America Berman Topper Career Development Fellowship which funds and supports this research, in addition to generous funding from the CHDI Foundation and the Huntington Society of Canada. The SGC is a registered charity (number 1097737) that receives funds from AbbVie, Bayer Pharma AG, Boehringer Ingelheim, Canada Foundation for Innovation, Eshelman Institute for Innovation, Genome Canada through Ontario Genomics Institute [OGI-055], Innovative Medicines Initiative (EU/EFPIA) [ULTRA-DD grant no. 115766], Janssen, Merck KGaA, Darmstadt, Germany, MSD, Novartis Pharma AG, Ontario Ministry of Research, Innovation and Science (MRIS), Pfizer, São Paulo Research Foundation-FAPESP, Takeda, and Wellcome.