Kin4 catalytic kinase activity is required for Kin4–Lte1 interaction. (A) Representative frames and fluorescence intensity line traces of cells expressing KIN4-GFP LTE1-3Cherry. Line profiles above the images represent the fluorescence intensities (FI) in arbitrary units (A.U.), measured for the indicated rectangular area, for Kin4-GFP (green lines) and Lte1-3Cherry (red lines). Note that FI is not comparable between cells. Cell boundaries in each graph are indicated as M and D, and bud neck region as BN. Bar, 5 µm. (B) LTE1 and LTE1-9Myc strains carrying KIN4-6HA (WT), KIN4-6HA elm1Δ, and KIN4-T209A-6HA were subjected to immunoprecipitation using anti-Myc beads. (C) Interaction between Lte1-9Myc and Kin4-6HA was investigated in RTS1 (WT, wild type) and rts1Δ cells upon immunoprecipitation of Lte1-9Myc with anti-Myc beads. (D) Localization of Kin4-GFP and Kin4-T209A-GFP in strains carrying LTE1-3Cherry (no overexpression) and Gal1-LTE1-3Cherry (overexpression), growing in galactose-containing medium. Bars, 5 µm.