Fig. 1
ATAD3A binds to Drp1 in HD. a Affinity purification followed by tandem mass spectrometry analysis was conducted to identify Drp1-interacting proteins in striatal neuronal cells derived from HD patient-iPS or normal subject-iPS cells (also see Supplementary Fig. 1A). The molecular and cellular functions of the Drp1 interactors in HD patient-derived neuronal cells are shown. b Upper: cellular location of the Drp1 interactors in HD neuronal cells. In particular, 32% of proteins are located on the mitochondria. ATAD3A ranked as a top candidate. Lower: Among mitochondrial candidates, mitochondrial nucleoid organization and energy production are enriched, and each account for up to 25% of all mitochondrial candidates. Immunoprecipitation (IP) of total protein lysates was performed in HdhQ7 and HdhQ111 cells (c), in wildtype striatal cells exposed to 3-NP (5 mM for 4 h) (d), in striatal extracts of YAC128 mice (6 months old) or R6/2 mice (12 weeks old) or age-matched wildtype mice (e), and in fibroblasts of HD patient (HD1, GM4208, 35 years old, Male) or normal subject (Con1, Huf1) (f). Data are mean ± SEM. Student t test. n = 3. g Total protein lysates of frozen postmortem caudate nucleus of normal subjects and HD patients with different disease severity (grade 1 to grade 4, slight to severe) were subject to IP analysis. Nor: normal subject 5214; G1: HD 4283, grade 1; G2: HD 4557, grade 2; G3: HD 3573, grade 3; G4: HD 2903, grade 4. Patient information shown in Supplementary Fig. 1F. The data below the blots indicate the relative density of Drp1 in ATAD3A immunoprecipitates (Drp1/ATAD3A in IP analysis). h GST-Drp1 (2 µg) and ATAD3A-Flag (2 µg) purified proteins were incubated in vitro for 30 mins. Left: IP with anti-Flag antibodies followed by western blot with the indicated antibodies. Right: GST pull down analysis. All shown representative blots are from at least 3 independent experiments
