AU-rich element RNA-binding protein 1 (AUF1) (AUF1)

AU-rich element RNA-binding protein 1 (AUF1), also known as Heterogeneous nuclear ribonucleoprotein D (hnRNP D), is a critical regulator of post-transcriptional gene expression [UniProt: Q14103]. It functions by binding to AU-rich elements (AREs) located in the 3' untranslated regions (UTRs) of various mRNAs, including those encoding cytokines, oncoproteins, and cell cycle regulators [NCBI Gene: 3184]. AUF1 exists as four isoforms (p37, p40, p42, and p45) that are generated through alternative splicing; these isoforms can either promote the rapid degradation of target mRNAs by recruiting the exosome or stabilize them, depending on the cellular context and the specific isoform involved [PMID: 11500481]. In cancer, AUF1 is frequently overexpressed and contributes to malignancy by stabilizing oncogenic transcripts such as c-Myc and Cyclin D1, while in inflammatory contexts, it regulates the half-life of pro-inflammatory cytokine mRNAs like TNF-alpha and IL-6 [PMID: 23533556]. Beyond mRNA turnover, AUF1 is also involved in telomere maintenance by binding to telomeric repeat sequences and interacting with telomerase [UniProt: Q14103]. Although no specific clinical drugs currently target AUF1, it is an active area of research for small molecule inhibitors and antisense therapies aimed at correcting mRNA dysregulation in cancer and chronic inflammation [PMID: 25448242].

Other names

Heterogeneous nuclear ribonucleoprotein D0HNRNPDhnRNP Dp37AUF1p40AUF1p42AUF1p45AUF1

AUF1 acts by binding to AU-rich elements (AREs) in the 3' untranslated regions of target mRNAs, where it recruits the exosome complex and other ribonucleases to facilitate rapid mRNA degradation [UniProt: Q14103]. Depending on the specific isoform (p37, p40, p42, or p45) and the cellular environment, it can also stabilize certain transcripts or modulate their translation, thereby controlling the expression of proteins involved in inflammation, cell cycle, and apoptosis [PMID: 23533556, PMID: 11500481].