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1. The process of formation of poly(adenylic acid).
2. The covalent modification of a macromolecule (for example, mRNA) by the formation of a polyadenylyl moiety covalently linked to the macromolecule.
polyadenylationThe process by which a sequence of polyadenylic acids (adenosine ribonucleotides) is added to the end of a spliced RNA after its transcription from DNA, resulting in mature mRNA. This addition on the RNA molecule is sometimes referred to as a poly-A tail, and commonly contains several-hundred bases.
polyadenylationaddition of a sequence of ADENINE NUCLEOTIDES to the 3′-end of most eukaryotic RNA molecules, after their TRANSCRIPTION. The sequence is often called a.poly(A) tail.
the addition of up to 250 adenylate residues to the 3′ end of eukaryotic mRNAs to form a so-called poly(A) tail. The primary transcript is cleaved by a specific endonuclease that recognizes the sequence AAUAAA which is also referred to as a polyadenylation signal sequence. The poly(A) tail protects the mRNA from digestion with nuclease and greatly increases the efficiency of translation.