CHN-1 interacts with UBC-13 and VPS-34. (A and D) Schematic diagram showing domains and truncations of CHN-1 (A) and VPS-34 (D), which were used to examine CHN-1–UBC-13 and CHN-1–VPS-34 interactions. (B, C, and E–H) The interaction between CHN-1 and UBC-13 (B and C), and CHN-1 and VPS-34 (E–H), were examined by yeast two-hybrid analyses (B, E, and G) and GST pulldown assays (C, F, and H). IB, immunoblot. The CHN-1–UBC-13 interaction occurs through the U-box domain of CHN-1 (B) and the SPA motif of UBC-13 (B and C). The CHN-1–VPS-34 interaction is mediated by the C2 domain of VPS-34 (E and F) and the TPR and helical (HH) domains of CHN-1 (G and H).