Polyuridylation, also called oligouridylation, is the addition of several

uridine Uridine (symbol U or Urd) is a glycosylated pyrimidine analog containing uracil attached to a ribose ring (or more specifically, a ribofuranose) via a β-N1- glycosidic bond. The analog is one of the five standard nucleosides which make up nuc ...

nucleotides to the 3' end of an

RNA Ribonucleic acid (RNA) is a polymeric molecule that is essential for most biological functions, either by performing the function itself (non-coding RNA) or by forming a template for the production of proteins (messenger RNA). RNA and deoxyrib ...

. Cytoplasmic poly(U) polymerases can add uridine nucleotides to both coding and non-coding RNAs. This addition may occur throughout a variety of RNA types including mRNAs, small RNAs,

miRNAs Micro ribonucleic acid (microRNA, miRNA, μRNA) are small, single-stranded, non-coding RNA molecules containing 21–23 nucleotides. Found in plants, animals, and even some viruses, miRNAs are involved in RNA silencing and post-trans ...

, siRNAs, guide RNAs, or piRNAs. Polyuridylation has been shown to play a role in gene regulation as an evolutionarily conserved process in

eukaryotes The eukaryotes ( ) constitute the domain of Eukaryota or Eukarya, organisms whose cells have a membrane-bound nucleus. All animals, plants, fungi, seaweeds, and many unicellular organisms are eukaryotes. They constitute a major group of ...

. One group of RNAs that can be polyuridylated are histone mRNAs that lack a

poly(A) tail Polyadenylation is the addition of a poly(A) tail to an RNA transcript, typically a messenger RNA (mRNA). The poly(A) tail consists of multiple adenosine monophosphates; in other words, it is a stretch of RNA that has only adenine bases. In euka ...

. Polyuridylation of a histone mRNA promotes its degradation, involving the exosome. Other RNAs in ''

Arabidopsis ''Arabidopsis'' (rockcress) is a genus in the family Brassicaceae. They are small flowering plants related to cabbage and mustard. This genus is of great interest since it contains thale cress (''Arabidopsis thaliana''), one of the model organ ...

'' and

mouse A mouse (: mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus'' ...

have been seen to be polyuridinylated after cleavage.

References

RNA {{molecular-biology-stub