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Updated: May 12, 2026

Gene-targeted Random Mutagenesis to Select Heterochromatin-destabilizing Proteasome Mutants in Fission Yeast
Published on: May 15, 2018
Processing of intervening sequences: a new yeast mutant which fails to excise intervening sequences from precursor
Abstract:
By using conditional loss of suppression an an assay, we have been successful in screening for a yeast mutant which is defective in tRNA processing. The los1-1 mutation causes an accumulation of a subset of precursor tRNAs at the nonpermissive temperature. These pre-tRNAs are like those which accumulate in the yeast mutant ts 136 (rna1) in that they have transcribed intervening sequences. The mutations at los1-1 and rna1 complement and segregate independently of each other. The los1-1 mutation affects the expression of all 8 tyrosine-inserting suppressor loci, but does not seem to affect rRNA or mRNA synthesis.
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