Figure 7.

Inhibition of the switch from apical to isotropic bud growth does not preserve bud cortex-associated cable assembly in the absence of actin cables. (A) GAL-CLN2–bearing wild-type (ABY2251) and tpm1-2 tpm2Δ (ABY 2252) cells either were (+Gal) or were not (-Gal) induced to overproduce Cln2p for 4 h at the indicated temperatures and observed by differential interference contrast microscopy or stained to show Tpm1p distribution. Arrows indicate bud tips with associated Tpm1p. (B) Wild-type (Y1239) or GAL-CLN2-bearing (ABY2251) cells induced for 4 h were grown at 18°C and stained for Myo2p. Tpm2Δ (ABY945), cdc10-1 tpm2Δ (ABY1637), and cdc12-6 tpm2Δ (AY1639) cells were grown at 35°C for 1 h before staining to show Myo2p distribution. One hundred cells of each strain with medium-sized and/or elongated buds were scored for the presence of Myo2p at the bud tip (black), at the bud tip and the neck (gray), at the bud neck (white), or not localized (blank). (C) Tpm1-2 tpm2Δ GAL-CLN2 cells (ABY2252) were subjected to the indicated conditions and stained to show Myo2p distribution. (D) Tpm1-2 tpm2Δ (ABY944) cells, tpm1-2 tpm2Δ GAL-CLN2 (ABY2252) cells grown 4 h in galactose, tpm1-2 tpm2Δ cdc10-1 (ABY1639) cells, and tpm1-2 tpm2Δ cdc12-6 (ABY1643) cells were shifted to 34.5°C for 2 or 60 min before restoration to 18°C for 1 min and Myo2p localized by immunofluorescence microscopy. One hundred medium-budded cells of each were scored for the presence of Myo2p at the bud tip (black), at the bud tip and neck (gray), at the bud neck (white), or not localized (blank).