Figure 2

uORF2b contributes to poor translatability of the AtbZip11 leader in the eif3h mutant. (a) Schematic of the arrangement of uORFs in the AtbZip11 leader. uORF2b was mutated by changing its start codon into a stop codon. (b) Translation efficiencies of the AtbZip11 leader lacking uORF2b in three different organs of two-week-old seedlings. The number of lines examined is indicated (n), as are p values derived from pairwise t-tests. For details see legend to Figure 1. (c) Summary of transgenic reporter gene translation assays on six different leader sequences. The number of transgenic lines examined is indicated for each leader, as is the number of uORFs per leader. The letters a and b indicate homogeneous subsets as determined by ANOVA/Tukey test. Thus, leaders that do not share the same letter (a, b) differ significantly in their dependence on the eIF3h protein. SE, standard error. (d) Reverse-transcriptase PCR analysis of FLUC mRNA levels in representative transgenic lines harboring TL-FLUC, AtbZip11-FLUC or AtbZip11/2b-FLUC transgenes. The EF1α mRNA was analyzed as a control for equal mRNA levels. The ethidium-bromide stained gels shown here are consistent with other repeat experiments performed with other subsaturating numbers of PCR cycles.