Ribosomal movement impeded at a pseudoknot required for frameshifting.

Tu, C; Tzeng, T H; Bruenn, J A

Ribosomal movement impeded at a pseudoknot required for frameshifting.

Authors

Tu, C

Tzeng, T H

Bruenn, J A

Publisher

National Academy of Sciences

Description

Translational frameshifting sometimes occurs when ribosomes encounter a "shift" site preceding a region of unusual secondary structure, which in at least three cases is known to be a pseudoknot. We provide evidence that ribosomes have a decreased rate of movement through a pseudoknot required for frameshifting. These paused ribosomes are directly situated over the shift sequence. Ribosomal pausing appears to be necessary but not sufficient for frameshifting. IMAGES: