(A) Tetrad dissection of heterozygous diploid Y1F CTD strain (Y1F). Y1F CTD in haploid tetrads marked with NAT resistance and is present in all small-size tetrads. Yeast spot assay comparing growth of WT, CONS, and two Y1F clones, with serial fivefold dilutions, on rich or synthetic complete (SC) medium at 30°C, or on rich medium at indicated temperature, for indicated number of days. (B) Cell-cycle assay showing unsynchronized cells stained with propidium iodide, the two peaks representing cells in G1/G0 and G2, respectively. (C) Western blot analysis of cell lysates derived from WT and Y1F strains using antibodies recognizing the N-terminus of Rpb1 (y80), unphosphorylated consensus repeats (8WG16), Ser2P (3E10 and H5), Ser5P (3E8), Tyr1P (3D12) and GAPDH as indicated. (D) Western blot analysis of an Rpb1 co-IP (using y-80), probing for Ctk1 interaction (using 3HA tagged Ctk1 and HA antibody) with RNAP II (normalized to Rpb3). 5% inputs shown. All results shown are representative of three independent experiments.