Figure 4
From: Multiple E3s promote the degradation of histone H3 variant Cse4
Ubr1 E3 regulates Cse4 turnover. (A) Ubr1 associates with Cse4 in vivo. A plasmid bearing HA-Cse4 or Flag-Ubr1 and/or a control vector were transformed into yeast cells. Proteins were extracted from the cells indicated and incubated with IgG beads coated with Flag or HA antibody. The samples were resolved by SDS-PAGE and visualized by western blotting using Flag or HA antibody as indicated. The identity of the bands is shown to the left of the panels. (B,C) Cse4 degradation in wild-type and ubr1Δ cells was determined and quantified as above. (D) Reduced Cse4 ubiquitylation in ubr1Δ cells. (E) Ubr1 is involved in the degradation of endogenously expressed Cse4-GFP. Expression shut-off analysis of Cse4 tagged with GFP at its normal chromosomal locus was carried out in wild-type and ubr1Δ cells. Cse4-GFP was immunoprecipitated by a GFP antibody and then analyzed by western blotting. (F) Quantitation of the data in E.
