HILPDA is a PPARγ target gene in
adipocytes. (a and b) Top 20 of most highly induced genes following gene
expression profiling of (a) SGBS and (b) hMADS adipocytes treated with 0.5
μM rosiglitazone or dimethylsulfoxide control for 6 hours. Fold change
was calculated by dividing gene expression values of rosiglitazone-treated
adipocytes by values of control-treated adipocytes. (c) Undifferentiated 3T3-L1
fibroblasts and fully differentiated 3T3-L1 adipocytes were exposed to 10
μM rosiglitazone or dimethylsulfoxide control for 24 hours and
subsequently analyzed for Hilpda mRNA (left) and HILPDA
protein (right). Gene expression levels of control-treated fibroblasts were set
at one. (d) Pparg and Hilpda mRNA expression
in 3T3-L1 adipocytes that had been treated with siCtrl or siRNA against
Pparg (siPparg) from the start of
differentiation and analyzed at day 5. (e) PPARG and
HILPDA mRNA expression in SGBS adipocytes that had been
treated with siCtrl or siRNA against Pparg
(siPPARG) from the start of differentiation and analyzed at
day 5. (f) Fully differentiated 3T3-L1 adipocytes were trypsinized, replated at
70% confluency, incubated with siCtrl or siPparg, and analyzed
for the gene expression levels of Pparg and
Hilpda after 72 hours. Gene expression levels of
siCtrl-treated adipocytes were set at one. Data are mean ± standard
error of the mean. Asterisks indicate significant differences according to
Student t test relative to (c) control-treated fibroblasts or
adipocytes or relative to (d–f) siCtrl-treated adipocytes;
**P < 0.01. Adip., adipocytes; Fibr.,
fibroblasts.