Figure 2.

(A) Mapping by yeast two-hybrid analysis of the regions needed in CHMP1B for interaction with IST1. Binding to CHMP1A was used as a positive control; the regions of VPS4 required for interaction with IST1. LIP5 was used as a positive control (B); and the regions of IST1 required for interaction with CHMP1A, CHMP1B, VPS4, or LIP5 (C). Error bars indicate the SD from the mean of triplicate measurements. (D) Micrographs showing that endogenous hIST1 is recruited to aberrant endosomes in the presence of YFP-VPS4 E228Q. Left, images acquired with YFP (pseudocolored in green); middle, images acquired with Alexa594 (pseudocolored in red); and right, overlaid images. A higher magnification of the boxed areas is shown in all panels and DNA is shown in blue. Bar, 10 μm.