ITPR1 and Huntington disease: To confirm that HAP1A activates SOCE by increasing IP3R1 activity in the present HD model, YAC128 MSN cultures that overexpressed HAP1A-pLenti-GFP or pLenti-GFP as a control and p49-dTomato or p30-dTomato corresponding to GST-tagged IP3R1 sponge or a control fragment were used for the Ca2+ measurements that were performed according to the protocol that is shown in Figure 6C.