Tales of poly(A): a review

Gene. 1990 Jul 16;91(2):151-8. doi: 10.1016/0378-1119(90)90082-3.

Abstract

Until recently, evidence to support a translational role for the 3'-poly(A) tract of eukaryotic mRNAs has been mostly indirect, including: a correlation between the adenylation status of individual mRNAs and their translatability in vivo or in vitro, the demonstration that exogenously added poly(A) is a potent competitive inhibitor of the translation of poly(A)+mRNA, but not poly(A)-mRNAs in vitro, and a correlation between the abundance and stability of poly(A)-binding proteins (PABPs) and the rate of translational initiation in vivo. However, more recent studies demonstrate directly that poly(A)+mRNAs can initiate translation more efficiently than poly(A)-mRNAs, and indicate that this effect is: (i) targeted to the formation of 80S initiation complexes, and (ii) likely to be mediated by the cytoplasmic PABP. We suggest that the 3'-poly(A) tail should be considered a translational enhancer which may stimulate translational initiation in much the same way that transcriptional enhancers are thought to stimulate transcriptional initiation.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Animals
  • Carrier Proteins / metabolism
  • Cytoplasm / metabolism
  • Gene Expression Regulation
  • Models, Genetic
  • Poly A / genetics*
  • Poly A / metabolism
  • Protein Biosynthesis*
  • RNA, Messenger / genetics*
  • RNA, Messenger / metabolism

Substances

  • Carrier Proteins
  • RNA, Messenger
  • Poly A