Global view on the metabolism of RNA poly(A)-tails in yeast Saccharomyces cerevisiae
The polyadenosine tail (poly[A]-tail) is a universal modification of eukaryotic messenger RNAs (mRNAs) and non-coding RNAs (ncRNAs). In budding yeast, Pap1-synthesized mRNA poly(A)-tails enhance export and translation, whereas the Trf4/5-mediated polyadenylation of ncRNAs facilitates degradation by the exosome. Using Direct RNA Sequencing, we decipher the extent of poly(A)-tail dynamics in yeast defective of all relevant exonucleases, deadenylases, and poly(A)-polymerases. Predominantly ncRNA poly(A)-tails are 20-60 As long. Poly(A)-tails of newly made mRNAs are 50 adenosine long on average with a upper limit of 200 As. Extensive exonucleolysis by Trf5-assisted nuclear exosome and cytoplasmic deadenylases trim mRNA poly(A)-tails to the lengths of 40 adenosines on average. Surprisingly PAN2/3 and CCR4-NOT deadenylase complexes have a large pool of non-overlapping substrates mainly defined by expression level. Finally, we demonstrate that mRNA poly(A)-tail length strongly responds to growth conditions such as heat and nutrient deprivation.
Steps to reproduce
For experimental procedures please refer to material and methods for details. This dataset only contains Northern and qPCR analysis, for Direct RNA Sequencing datasets refer to the publication for accession numbers.