A family of poly(U) polymerases

The GLD-2 family of poly(A) polymerases add successive AMP monomers to the 39 end of specific RNAs, forming a poly(A) tail. Here, we identify a new group of GLD-2-related nucleotidyl transferases from Arabidopsis, Schizosaccharomyces pombe, Caenorhabditis elegans, and humans. Like GLD-2, these enzymes are template independent and add nucleotides to the 39 end of an RNA substrate. However, these new enzymes, which we refer to as poly(U) polymerases, add poly(U) rather than poly(A) to their RNA substrates.