Fig. 3.

Unopposed fusion mediates mitochondrial tubulation during starvation. (A, C, and D) MEFs were treated with the media indicated for 2.5 h (A) or 5 h (C and D) and lysed in ice-cold lysis buffer A, and samples were subjected to immunoblotting against Mfn1, Mfn2, Opa1, Drp1, and pS616-Drp1 as indicated (whole-cell lysates were probed in A and C; isolated mitochondria were probed in D). (B) At 16 h after transfection with the indicated YFP-tagged Drp1 constructs, cells were treated with full medium or starved in D-GSG for 2 h. Mitochondrial morphology was scored as described in Fig. 1 (n = 3).