Deadenylation of the unstable mRNA encoded by the yeast MFA2 gene leads to decapping followed by 5'-->3' digestion of the transcript. Journal Article uri icon



  • The first step in the decay of some eukaryotic mRNAs is the shortening of the poly(A) tail. To examine how the transcript body was degraded after deadenylation, we followed the decay of a pulse of newly synthesized MFA2 transcripts while utilizing two strategies to trap intermediates in the degradation pathway. First, we inserted strong RNA secondary structures, which can slow exonucleolytic digestion and thereby trap decay intermediates, into the MFA2 5' UTR. Following deadenylation, fragments of the MFA2 mRNA trimmed from the 5' end to the site of secondary structure accumulated as full-length mRNA levels decreased. In addition, in cells deleted for the XRN1 gene, which encodes a major 5' to 3' exonuclease in yeast, the MFA2 transcript is deadenylated normally but persists as a full-length mRNA lacking the 5' cap structure. These results define a mRNA decay pathway in which deadenylation leads to decapping of the mRNA followed by 5'-->3' exonucleolytic degradation of the transcript body. Because the poly(A) tail and the cap structure are found on essentially all mRNAs, this pathway could be a general mechanism for the decay of many eukaryotic transcripts.

publication date

  • April 1, 1994

has restriction

  • gold

Date in CU Experts

  • February 21, 2014 11:14 AM

Full Author List

  • Muhlrad D; Decker CJ; Parker R

author count

  • 3

Other Profiles

International Standard Serial Number (ISSN)

  • 0890-9369

Electronic International Standard Serial Number (EISSN)

  • 1549-5477

Additional Document Info

start page

  • 855

end page

  • 866


  • 8


  • 7