Lysine residue mutations in the Fus2p/Rvs161p amphiphysin-like dimer affect Cdc42p ZCF localization. (A) Representative images of prezygotes. GFP–CDC42 fus2Δ rvs161Δ (MY16013) cells were transformed with both a FUS2–mCherry₁₀₄ plasmid (pMR5821) and a Rvs161p–Flag₈₅ (pMR7155) or Rvs161p–Flag₈₅ and mCherry–fus2^con (pMR7158) or FUS2–mCherry₁₀₄ and GFP–rvs161^loop (pMR7157) and mated against a fus1Δfus2Δ (JY429) for 2.5 h at 30°, fixed with 2% formaldehyde, and imaged. (B) Quantification of Cdc42p ZCF localization. Fluorescence intensities across the ZCF were measured for all prezygotes, interpolated to account for differences in ZCF length, and plotted as a ratio of the center values to the mean of the two edges. Data were pooled from three independent experiments. n ≥ 54 for each strain. Bars, 2 µm.