Fig. 2
Contributions of S. cerevisiae Srv2/CAP domains to its synergistic depolymerization with Cofilin. a Domain diagram of Srv2 constructs used in this study. Blue asterisk indicates location of the Srv2-90 mutation. Black asterisk on Srv2ΔCARP indicates the location of its single cysteine, which was used for Cy5-labeling. b Rates (±sd) of pointed-end depolymerization in the presence of 1 μM Cof1 and/or 0.5 μM Srv2 or Srv2-90. Right: Magnified view. *statistical comparison by two-sample t test against Control (p < 0.05); †comparison with Cof1 (p < 0.05). ns no evidence for significance at p = 0.05. Srv2, Cof1 and Srv2-Cof1 data are the same as in Fig. 1e. Number of filament ends analyzed for each condition (left to right): 149, 28, 55, 38, 110 and 37. c Rates of pointed-end depolymerization in the presence of 1 μM Cof1 and/or 0.5 μM Srv2 or N-Srv2. *statistical comparison by two-sample t test against Srv2 + Cof1 (p < 0.05); †statistical comparison by two-sample t test against Srv2 (p < 0.05); ns no evidence for significance at p = 0.05 from Srv2 + Cof1 condition. Srv2−Cof1 data are the same as in Fig. 1e. Number of filament ends analyzed for each condition (left to right): 149, 106, 57 and 68. d Rates of pointed-end depolymerization in the presence of 1 μM Cof1, 1 μM Twf1 and 160 nM N-Srv2 alone or in stated combinations. *statistical comparison by two-sample t test against Cof1 + N-Srv2 (p < 0.05). ns no evidence for significance at p = 0.05. Number of filament ends analyzed for each condition (left to right): 68, 61, 77, 33, and 70. e Rates (±sd) of pointed-end depolymerization as a function of N-Srv2 concentration in presence of 1 μM Cof1. N = 32–262 filaments analyzed per concentration. Fit to the Michaelis−Menten equation (red) yielded KM = 50 ± 10 nM; kcat = 53 ± 8 subunits s−1. Inset: magnified view. Source data are provided as a Source Data file. All experiments were performed at least three independent times, and yielded similar results. Data shown are from one experiment.
