Dead End Homolog 1 (DND1)

The deduced 353-amino acid protein contains a single-strand RNA-binding domain in the N-terminus and shares 34% sequence identity with zebrafish Dnd1.

MicroRNAs (miRNAs) are short noncoding RNAs that bind to complementary sequences in the 3-prime UTRs of target mRNAs and inhibit their expression.Introduction of DND1 abolished the interaction between miR221 and the 3-prime UTR of p27 mRNA and countered the downregulation of p27 expression by miR221. DND1 bound a uridine-rich region in the 3-prime UTR of p27 mRNA that is near the miR221-binding site and prevented miR221 binding. At least 1 of the 2 uridine-rich regions in the p27 3-prime UTR and the RNA-binding domain of DND1 were required to rescue p27 expression.