RNA recognition motif (RRM) found in peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1alpha, or PPARGC-1-alpha) and similar proteins
This subgroup corresponds to the RRM of PGC-1alpha, also termed PPARGC-1-alpha, or ligand effect modulator 6, a member of a family of transcription coactivators that plays a central role in the regulation of cellular energy metabolism. As an inducible transcription coactivator, PGC-1alpha can interact with a broad range of transcription factors involved in a wide variety of biological responses, such as adaptive thermogenesis, skeletal muscle fiber type switching, glucose/fatty acid metabolism, and heart development. PGC-1alpha stimulates mitochondrial biogenesis and promotes oxidative metabolism. It participates in the regulation of both carbohydrate and lipid metabolism and plays a role in disorders such as obesity, diabetes, and cardiomyopathy. PGC-1alpha is a multi-domain protein containing an N-terminal activation domain region, a central region involved in the interaction with at least a nuclear receptor, and a C-terminal domain region. The N-terminal domain region consists of three leucine-rich motifs (L1, NR box 2 and 3), among which the two last are required for interaction with nuclear receptors, potential nuclear localization signals (NLS), and a proline-rich region overlapping a putative repression domain. The C-terminus of PGC-1alpha is composed of two arginine/serine-rich regions (SR domains), a putative dimerization domain, and an RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain). PGC-1alpha could interact favorably with single-stranded RNA.