Figure 1.
uORF attributes that affect mORF translation include the following: (1) The efficiency of initiation at the uORF start codon, impacted by the start codon context sequence, controls leaky scanning. (2) The length of the uORF and the time it takes to translate the uORF affect the ability of a ribosome to resume scanning and reinitiate at a downstream start site following translation termination at the uORF stop codon. (3) The distance between the uORF stop codon and downstream start codon impacts the ability of a ribosome sliding down the mRNA after termination at the uORF stop codon to reacquire the initiation factors and Met-tRNAMeti required to initiate at a downstream start site.