|Human, Mouse, Rat|
Application Methods: Chromatin IP, Immunoprecipitation, Western Blotting
Background: Reverse orientation c-erbA gene α (Rev-erbα, EAR-1, or NR1D1) is a widely expressed member of the orphan nuclear receptor family of proteins (1). Rev-erbα is highly expressed in adipose tissue, skeletal muscle, brain and liver, and regulates cellular proliferation and differentiation. Expression increases during differentiation in adipocytes and ectopic expression of Rev-erbα potentiates the adipocyte differentiation of 3T3-L1 cells (2). In addition, expression oscillates with circadian rhythm in liver cells and Rev-erbα regulates expression of BMAL1, ApoA-I and ApoC-III, all key regulators of circadian rhythm (3-7). Phosphorylation of Rev-erbα Ser55 and Ser59 by GSK-3β appears to stabilize Rev-erbα protein levels and is important for synchronizing and maintaining the circadian clock (8). Rev-erbα also regulates inflammation by targeting the NF-κB responsive genes IL-6 and COX-2 (9). Rev-erbα lacks the activation function 2 domain required for ligand-dependent activation of transcription by other members of the nuclear receptor family; thus it behaves as a constitutive repressor protein, recruiting the nuclear receptor co-repressor (N-CoR)/HDAC3 complex to target genes to repress transcription (10).
Application Methods: Western Blotting
Background: PPARγ coactivator-1α (PGC-1α) was originally identified as a transcriptional coactivator whose expression closely correlated with adaptive thermogenesis following exposure to cold temperatures (1). Named for its association with the nuclear receptor peroxisome-proliferator activated receptor (PPARγ), PGC-1α interacts with a diverse array of transcription factors to regulate numerous aspects of cell physiology (2). PGC-1α helps to regulate cell processes important in adaptive thermogenesis and energy metabolism, including the related functions of glucose uptake, gluconeogenesis, insulin secretion, and mitochondrial biogenesis (3). Long thought to be a potential therapeutic target for the treatment of type II diabetes, obesity, cardiomyopathy, or other metabolic disorders (reviewed in 4), a recent functional survey found no obvious differences in PPARγ activity associated with recognized PGC-1α variants (5).