Terminal uridylyltransferase 1, U6 snRNA-specific (TUT1)

Terminal uridylyltransferase 1, U6 snRNA-specific (TUT1) is a multifunctional enzyme that acts as both a terminal uridylyltransferase and a non-canonical nuclear poly(A) polymerase. TUT1 localizes to nuclear speckles and is best known for catalyzing the uridylylation of U6 small nuclear RNA (snRNA), a critical RNA species in the spliceosome for mRNA splicing. This enzyme adds oligo-uridines to the 3′ end of newly transcribed U6 snRNA, restoring its characteristic terminal structure and ensuring proper maturation and function in pre-mRNA splicing. Beyond this, TUT1 has context-dependent poly(A) polymerase activity, particularly in the oxidative stress response, where it mediates polyadenylation and 3′ end cleavage of specific mRNAs by facilitating CPSF (cleavage and polyadenylation specificity factor) complex assembly on target RNAs. Structurally, TUT1 contains zinc finger (ZF), RNA recognition motif (RRM), and KA-1 domains along with its catalytic core, allowing multivalent, transient binding to RNA substrates. Its activities help coordinate post-transcriptional gene regulation and have been implicated in cellular stress responses as well as in disease states such as cancer, notably lung cancer where it is upregulated[1][2][3]. No drugs or direct small-molecule inhibitors are currently annotated as interacting with TUT1, and there are no clear biomarkers or safety concerns described in the current literature[3]. TUT1 is a member of terminal nucleotidyltransferases, both as a uridylyltransferase (U6 snRNA-specific) and a regulatory poly(A) polymerase for specific transcripts[2][3]. The enzyme is essential for the correct processing of U6 snRNA and also contributes to alternative polyadenylation of oxidative stress response genes[2][3].

Other names

Speckle targeted PIP5K1A-regulated poly(A) polymeraseStar-PAPRBM21RNA-binding protein 21U6-TUTasePAPD2TENT1RNA uridylyltransferaseSTARPAPnuclear speckle-targeted PIPK1A-regulated poly(A) polymerasepoly(A) polymerase associated domain containing 2U6 snRNA-specific terminal uridylyltransferase 1FLJ22347FLJ22267FLJ21850RNA-binding motif protein 21up-regulated in lung cancer 6