Step-wise formation of eukaryotic double-row polyribosomes and circular translation of polysomal mRNA.

ABSTRACT: The time course of polysome formation was studied in a long-term wheat germ cell-free translation system using sedimentation and electron microscopy techniques. The polysomes were formed on uncapped luciferase mRNA with translation-enhancing 5' and 3' UTRs. The formation of fully loaded polysomes was found to be a long process that required many rounds of translation and proceeded via several phases. First, short linear polysomes containing no more than six ribosomes were formed. Next, folding of these polysomes into short double-row clusters occurred. Subsequent gradual elongation of the clusters gave rise to heavy-loaded double-row strings containing up to 30-40 ribosomes. The formation of the double-row polysomes was considered to be equivalent to circularization of polysomes, with anti

SUBMITTER: Kopeina GS 

PROVIDER: S-EPMC2377419 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature