Stable expression of AtCyp59 in Arabidopsis cells results in cell growth arrest and decrease in CTD phosphorylation. (A) Western blot analysis of transgenic, kanamycin resistant Arabidopsis calli expressing TAP tagged AtCyp59 (upper panel). For comparison transgenic calli expressing TAP-tagged PRH75 (lower panel) were analyzed in parallel. Both proteins were detected with anti-HA antibody. (B) Analysis of the phosphorylation status of the RNA pol II CTD in Arabidopsis calli expressing TAP-tagged AtCyp59. (Top panel) Analysis of the expression of AtCyp59 (lanes 1–3). For comparison, protein extract from callus expressing Arabidopsis U1 snRNP-specific protein 70K was loaded as a control (lane 4). The same protein extracts were analyzed with antibodies against the CTD (H14, second panel, and 8WG16, fourth panel). These two membranes were subsequently analyzed with antibodies against α-tubulin (panels below H14 and 8WG16 panels).
