ACBD5–VAPB binding, but not ACBD4–VAPB interaction, is sensitive to phosphatase treatment. (A) FLAG-ACBD4/5 was expressed in COS-7 cells, and lysates were treated with or without λPP. FLAG-ACBD4/5 was immunoprecipitated, and endogenous bound VAPB was detected by immunoblotting using FLAG/VAPB antibodies. Constructs with mutations in the FFAT-like motif (mFFAT) were used as a negative control. (B) Schematic overview of replacement of the ACBD4 FFAT-like motif region (bold) by that of ACBD5. (C) Myc-ACBD5 phospho mutants were expressed in COS-7 cells and immunoprecipitated to detect endogenous bound VAPB using Myc/VAPB antibodies. Source data are available for this figure: SourceData FS1.