Transcriptional coregulator of NF-kappa-B which facilitates binding of NF-kappa-B proteins to target kappa-B genes in a redox-state-dependent manner. May be required for efficient terminal myeloid maturation of hematopoietic cells. Has quercetin 2,3-dioxygenase activity (in vitro).
Subcellular locations: Nucleus, Cytoplasm
Predominantly localized in dot-like subnuclear structures. Cytoplasmic localization of PIR seems to positively correlate with melanoma progression.
Highly expressed in a subset of melanomas. Detected at very low levels in most tissues (at protein level). Expressed in all tissues, with highest level of expression in heart and liver.