FIG. 5.

The cap structure and the poly(A) tail synergistically activate cell-free translation in extracts deficient in Pat1p. Extracts from wild-type cells (WT) and from cells deficient in Pat1p (pat1Δ) were assayed for their ability to translate LUC mRNA carrying a cap structure (CapLUC) or a poly(A) tail (LUCpA) or both (CapLUCpA) under the same conditions, in which protein synthesis responded linearly to the mRNA concentrations. Luciferase production was determined by luminescence. Activities were measured under noncompetitive conditions in nuclease-treated extracts and under competitive conditions in the presence of endogenous RNA in untreated extracts. Five repeat experiments were performed. Error bars represent variations (about 15 to 20%) between individual experiments. RLU, relative light units.