Yeast mutant, rna 1, affects the entry into polysomes of ribosomal RNA as well as messenger RNA.

The entry of newly labeled ribosomal subunits and mRNA into polysomes was examined in the yeast mutant rna1. The entry of both types of RNA into polysomes is inhibited rapidly at the restrictive temperature. Analysis of the labeling of the ATP pool and the kinetics of synthesis and processing of mRNA at the restrictive temperature leads to the conclusion that the primary defect in the mutant affects transport of both ribosomes and messenger across the nuclear membrane.