Pirin (PIR)

Pirin is an Fe(II)-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.

Immunofluorescence studies indicated that pirin is localized in dot-like structures in the nucleus of mammalian cells. Antibodies against pirin recognized a single band in extracts of cells from several mammals, suggesting that pirin is conserved among mammals.