insight into how mRNAs transition between mRNP states capable of translation or deadenylation and mRNA decapp- ing. A second, and related issue, is that an understanding of mRNA degradation will require a broader understanding of mRNP biogenesis, dynamics, and how the speciﬁc proteins bound to individual mRNAs act, either in isolation or in combination, to modulate translation and mRNA degradation. A third area of interest will be in determining the relationship between mRNA degradation and transcription. This issue is of interest since several observations suggest that transcription and mRNA degradation are coupled. For example, dcp1Δ strains were observed to have prolonged decay rates of reporter mRNAs without a corresponding in- crease in steady-state levels, suggesting alterations in tran- scription (Muhlrad and Parker 1999b). In addition, strains lacking the decapping activator Edc1 were unable to induce new transcription during a shift in carbon source (Schwartz et al. 2003). 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