Genetic analysis of mutations affecting growth of Saccharomyces cerevisiae at low temperature

Abstract

A large number of genes control growth of the yeast Saccharomyces cerevisiae at low temperatures (<10°). Approximately 47% of the mutants selected for inability to grow at 4-5°C show increased sensitivity to cycloheximide. In 3 of 4 cases tested, supersensitivity to cycloheximide and inability to grow at the low temperature segregate together and thus appear to be effects of the same mutation. Since many cold sensitive mutants of bacteria have been found to have altered ribosomes and since cycloheximide resistance in yeast can be caused by ribosomal changes, this suggests that the mutants having low temperature sensitive growth may be defective in ribosome assembly processes at the low temperatures. Two of the lts loci, lts1 and lts3, have been located on chromosome VII and another two, lts4 and lts10 on chromosome IV. A mutation, cyh10, conferring cycloheximide resistance, but not cold sensitivity, has been located close to the centromere on chromosome II.