Figure 3.

AUG-Stop Affects B-Dependent Downregulation of NIP5;1.

(A) Schematic representation of 5′-NIP5;1(−306):LUC RNA. The thick line represents the mRNA sequence and open boxes represent uORFs.

(B) Effect of B on translation in vitro. RNA carrying 5′-NIP5;1(−306):LUC with or without a mutation in AUGUAA was translated in WGE. Means ± sd of relative LUC activities under various B conditions are shown (n = 3). Asterisks indicate significant reductions in RNA carrying ⁻¹²²AUGUAA (P < 0.05).

(C) Effects of NaCl, KNO₃, and KH₂PO₄ at 500 μM on reporter expression in vitro. RNA carrying 5′-NIP5;1(−306):LUC with or without a mutation in AUGUAA was translated in WGE. Means ± sd of relative LUC activities are shown (n = 3)

(D) and (E) Primer extension (D) and toeprint (E) analyses in WGE with 300 µM B (+B) or without B supplementation (−B). Signals are enlarged under the main image of the AUGUAA lane, and their means ± sd (n = 3) of relative intensities are shown. Asterisks indicate significant differences (P < 0.05).

(F) Nucleotide sequence around ⁻¹²²AUG-stop. Positions of PE (magenta) and TP signals (green) are marked. Ribosome occupation of RNA having the AUG codon positioned at the P-site is shown.