Synonyms:KIAA0191, PAPD3, Terminal uridylyltransferase 4, TUT4, TUTase 4, ZCCHC11 Background:Uridylyltransferase that mediates the terminal uridylation of mRNAs with short(less than 25 nucleotides) poly(A) tails, hence facilitating global mRNA decay(PubMed:25480299). Involved in microRNA(miRNA)-induced gene silencing through uridylation of deadenylated miRNA targets. Also acts as a suppressor of miRNA biogenesis by mediating the terminal uridylation of some miRNA precursors, including that of let-7(pre-let-7), miR107, miR-143 and miR-200c. Uridylated miRNAs are not processed by Dicer and undergo degradation. Degradation of pre-let-7 contributes to the maintenance of embryonic stem(ES) cell pluripotency(By similarity). Does not bind RNA directly, but recruited to RNA targets by RNA-binding protein LIN28A. Also catalyzes the 3' uridylation of miR-26A, a miRNA that targets IL6 transcript. This abrogates the silencing of IL6 transcript, hence promoting cytokine expression(By similarity). May also suppress Toll-like receptor-induced NF-kappa-B activation via binding to T2BP. Does not play a role in replication-dependent histone mRNA degradation. Due to functional redundancy between ZCCHC6 and ZCCHC11, the identification of the specific role of each of these proteins is difficult.