PIR (gene)

Pirin is a protein that in humans is encoded by the PIR gene.
This gene encodes a member of the cupin superfamily. The encoded protein is a Fe-containing nuclear protein expressed in all tissues of the body and concentrated within dot-like subnuclear structures. Interactions with nuclear factor I/CCAAT box transcription factor as well as B cell lymphoma 3-encoded oncoprotein suggest the encoded protein may act as a transcriptional cofactor and be involved in the regulation of DNA transcription and replication. Alternatively spliced transcript variants have been described.

Interactions

PIR has been shown to interact with BCL3.

Pirin in Bacteria

The pir gene is conserved in both bacteria and eukaryotes. In Pseudomonas stutzeri this protein exhibited quercetinase activity. In Streptomyces ambofaciens, a strain known to produce the antibiotic spiramycin, the pirA gene regulates the AcdB enzyme that catalyzes one of the first steps of beta-oxidation. Loss of the pirA gene causes a metabolic imbalance that reduces the amount of antibiotic produced. AcdB produces oxygen free radicals that influence the activity of PirA. PirA of Streptomyces ambofaciens has been shown to regulate the response to oxidative stress by binding to CatR, the catalase A regulator, thereby linking oxidative stress to beta-oxidation regulation.