Figure 9From: Retinoid X receptor and peroxisome proliferator-activated receptor-gamma agonists cooperate to inhibit matrix metalloproteinase gene expressionLG268 and rosiglitazone induce SUMOylation of their respective receptors and the unliganded partner. LG268 and rosiglitazone treatment increases SUMOylation of (a) peroxisome proliferator-activated receptor-gamma (PPARγ) and (b) retinoid X receptor (RXR). SW-1353 cells were treated with 1 hour of 50 nM LG268, 50 nM rosiglitazone, or both for pretreatment and then 1 hour of 1 ng/mL interleukin-1-beta (IL-1β) for stimulation. Cells were harvested in 1× radioimmunoprecipitation assay lysis buffer, and total protein was quantified. Two thousand micrograms of total cell protein and 4 μg of anti-SUMO1 antibody were used in each immunoprecipitation reaction. Immunoprecipitated proteins were resolved using PAGE; after transfer, Western blotting was performed with anti-PPARγ or anti-RXR antibody at a dilution of 1:2,000. Bands were visualized using enhanced chemiluminescence and overnight autorad exposure. IgG bands are displayed as a loading control. (a) Single arrowhead denotes high-molecular weight/2 × SUMO1-PPARγ band. (b) Double arrowhead denotes high-molecular weight/2 × SUMO1-RXR band; single arrowhead denotes low-molecular weight/1 × SUMO1-RXR band. Lane reference numbers 1P to 8P and 1R to 8R are displayed to facilitate description in the text. IP, immunoprecipitation; LG268, LG100268; Rosi, rosiglitazone; SUMO, small ubiquitin-like modifier; WB, Western blotting.Back to article page