Here you are: IMGT Web resources > IMGT Education

Polyadenylation (or Poly(A)) signal, site and tail

The polyadenylation or Poly(A) is the process required for the synthesis of messenger RNA (mRNA) in which an endonucleolityc RNA cleavage is coupled with synthesis of polyadenosine monophosphate (adenine base) on the newly formed 3' end. The sequence elements for polyadenylation include the polyadenylation signal (POLYA_SIGNAL) and the polyadenylation site (POLYA_SITE). In mRNA or cDNA the added stretch of polyadenosine monophosphate is the polyadenylation tail (POLYA_TAIL).

Polyadenylation signal

Polyadenylation site

Polyadenylation tail

Polyadenylation site
[1] Wahle E. and Keller W., Ann. Rev. Biochem., 61:419-440 (1992)
[2] Lefranc, M.-P. and Lefranc, G., The immunoglobulin FactsBook, Academic Press, London, 458 pages (2001) ISBN: 012441351X
[3] Manley J.-L. and Takagaki Y., Science, 274:1481-1482 (1996)