Fig. 4.

KIF3 regulates melanocyte pigmentation and forms a complex with Rab4A–rabenosyn-5–AP-3. (A) BF and IFM analysis of KIF3A or KIF3B-knockdown melanocytes. Black arrows indicate the loss of pigmentation. White arrows show the loss in KIF3A or PMEL staining, or clustering of EEA1 in KIF3A or KIF3B sh cells. White arrowheads point to the colocalization of PMEL with LAMP-2. Their colocalization coefficient (r) is indicated separately. Nuclei are stained with Hoechst 33258. The insets are a magnified view of the white boxed areas. Scale bars: 10 µm. (B,C) Immunoblotting analysis of melanosomal and lysosomal proteins, and PMEL fibrils in KIF3A or KIF3B-knockdown cells. Tubulin was used as a loading control. P1 and Mβ, full length and processed PMEL bands. *non-specific bands. Protein band intensities were quantified and are indicated on the gels. (D) Immunoprecipitation of Myc–KIF3A in HeLa cells. Both input and IP blots were probed as indicated.