Ribosomes in a stacked array: Elucidation of the step in translation elongation at which they are stalled during S-adenosyl-l-methionine-induced translation arrest of CGS1 mRNA

Background: S-Adenosyl-L-methionine arrests ribosomes on CGS1 mRNA at the pre-translocation step, and ribosomes stack behind it. Results: Puromycin reactivity of stacked ribosomes was intermediate between ribosomes at the pre- and post-translocation steps. Conclusion: Ribosomes are stacked at nine-codon intervals, and the majority are stalled at an early step of translocation. Significance: This study is the first report of ribosomal states in a stacked array.