Fig. 2.

Multiple point mutations to guanine. The ratio between the fluorescence level of the synthetic 5^′-UTRs from k ₂₆ to k ₃₈ and that of k ₁ are reported. The number of adenines or guanines in the upstream region is given below the leader sequence name (from k ₂₇ to k ₃₈). The subscripts −1, −2, and −3 indicate that an adenine is present in the extended Kozak sequence only at the corresponding position. Subscript i represents intermixed (see main text). Asterisks, p-value <0.05 vs. k ₁