Acts as a negative regulator of G1 to S cell cycle phase progression by inhibiting cyclin-dependent kinases. Inhibitory effects are additive with GADD45 proteins but occurs also in the absence of GADD45 proteins. Acts as a repressor of the orphan nuclear receptor NR4A1 by inhibiting AB domain-mediated transcriptional activity. May be involved in the hormone-mediated regulation of NR4A1 transcriptional activity. May play a role in mitochondrial protein synthesis.
Subcellular locations: Mitochondrion, Nucleus
Using N-terminally tagged constructs, has been found in the nucleus . C-terminally tagged constructs are targeted exclusively to mitochondria . This discrepancy may be explained by masking of a potential N-terminal mitochondrial targeting signal by the tag .
Widely expressed. Highly expressed in the thyroid gland, heart, lymph nodes, trachea and adrenal tissues. Expressed at lower level in liver skeletal muscle, kidney, pancreas, testis, ovary and stomach. Barely detectable in adrenal adenoma and papillary thyroid cancer.