Enzymatic addition of several adenine nucleotides to the 3′ end of mRNA molecules as part of the processing that primary RNA transcripts undergo prior to transport from the nucleus to the cytoplasm. The added segment is referred to as a “poly-A tail.” Histone mRNAs lack poly-A tails. See Chronology, 1971, Darnell et al.; posttranscriptional processing.
Subjects: Genetics and Genomics.