hide
Free keywords:
-
Abstract:
The rates of mRNA synthesis and degradation determine
cellular mRNA levels and can be monitored
by comparative dynamic transcriptome analysis
(cDTA) that uses nonperturbing metabolic RNA labeling.
Here we present cDTA data for 46 yeast strains
lacking genes involved in mRNA degradation and
metabolism. In these strains, changes in mRNA
degradation rates are generally compensated by
changes in mRNA synthesis rates, resulting in a buffering
of mRNA levels. We show that buffering of
mRNA levels requires the RNA exonuclease Xrn1.
The buffering is rapidly established when mRNA
synthesis is impaired, but is delayed when mRNA
degradation is impaired, apparently due to Xrn1-
dependent transcription repressor induction. Cluster
analysis of the data defines the general mRNA degradation
machinery, reveals different substrate preferences
for the two mRNA deadenylase complexes
Ccr4-Not and Pan2-Pan3, and unveils an interwoven
cellular mRNA surveillance network.