Heterogeneous Nuclear Ribonucleoprotein A1 (HNRPA1)

Heterogeneous nuclear ribonucleoprotein A1  belongs to the A/B subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs). This protein is exported from the nucleus, probably bound to mRNA, and is immediately re-imported. Its M9 domain acts as both a nuclear localization and nuclear export signal. The encoded protein is involved in the packaging of pre-mRNA into hnRNP particles, transport of poly A mRNA from the nucleus to the cytoplasm, and may modulate splice site selection. It is also thought have a primary role in the formation of specific myometrial protein species in parturition. Multiple alternatively spliced transcript variants have been found for this gene but only two transcripts are fully described. These variants have multiple alternative transcription initiation sites and multiple polyA sites.