To define the interactome of huntingtin protein (HTT) in human neurons, we assessed interactors of HTT with coimmunoprecipitation experiments with huntingtin antibody or polyqlutamine antibody (it only recognizes mutant huntingtin protein with abnormal polyqlutamine expansion) in striatal neurons differentiated from control and patient-derived iPSC lines (HD-iPSCs). GFP antibody used as a negative control.