Figure 3.
Complementation of cdk8-2 growth and aggregation defects. (A) Expression of the myc-Cdk8 and myc-Cdk8kd proteins was confirmed by western blotting. Samples were collected from vegetatively growing cells of each strain and resolved on a 12% SDS-PAGE gel, transferred to a nitrocellulose membrane and probed with the antibodies indicated. The blot was reprobed with an α-actin antibody to control for loading. (B) Complementation of slow-growth phenotype. Growth in HL-5 medium was assessed by counting cell number. The cdk8-2 and cdk8-2[myc-cdk8kd] strain eventually grew to a density of 2 x 107 cells/ml after 7-8days (data not shown). (C) Complementation of aggregation phenotype. Cells were developed on filters at 3 x 106 cells/ml at 22°C. Photographs were taken after 4 days. The scale bar in the bottom right hand panel represents 200 μm. (D) Complementation of spore viability defect. Fruiting bodies formed after developing with cAMP pulsing were harvested and spores assessed for viability as in Figure 2. Results showing statistically significant difference from Ax2bsR are marked with a * (p < 0.05 by student t-test).