1932

Abstract

The 3′-ends of both prokaryotic and eukaryotic mRNA are polyadenylated, but the poly(A) tracts of prokaryotic mRNA are generally shorter, ranging from 15 to 60 adenylate residues and associated with only 2–60% of the molecules of a given mRNA species. The sites of polyadenylation of bacterial mRNA are diverse and include the 3′-ends of primary transcripts, the sites of endonucleolytic processing in the 3′ untranslated and intercistronic regions, and sites within the coding regions of mRNA degradation products. The diversity of polyadenylation sites suggests that mRNA polyadenylation in prokaryotes is a relatively indiscriminate process that can occur at all mRNA's 3′-ends and does not require specific consensus sequences as in eukaryotes. Two poly(A) polymerases have been identified in . They are encoded by unlinked genes, neither of which is essential for growth, suggesting significant functional overlap. Polyadenylation promotes the degradation of a regulatory RNA that inhibits the replication of bacterial plasmids and may play a similar role in the degradation of mRNA. However, under certain conditions, poly(A) tracts may lead to mRNA stabilization. Their ability to bind S1 ribosomal protein suggests that poly(A) tracts may also play a role in mRNA translation.

Loading

Article metrics loading...

/content/journals/10.1146/annurev.biochem.66.1.173
1997-07-01
2024-06-13
Loading full text...

Full text loading...

/content/journals/10.1146/annurev.biochem.66.1.173
Loading
/content/journals/10.1146/annurev.biochem.66.1.173
Loading

Data & Media loading...

  • Article Type: Review Article
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error