Multiple mechanisms regulate expression of low temperature responsive (LOT) genes in Saccharomyces cerevisiae.

Using cDNA subtraction screening, we identified five Saccharomyces cerevisiae genes whose expressions is up-regulated when culture temperature was down-shifted from 30 to 10 degrees C. Among these LOT (low temperature-responsive) genes, three (LOT1, LOT2, and LOT3) were identical to FBA1, RPL2B, and NOP1, encoding a fructose biphosphate aldolase, a ribosomal protein L2B, and a nucleolar protein for rRNA processing, respectively. No functions were assigned for LOT5 and LOT6, which are identical to YKL183w and YLR011w, respectively. Northern hybridization analysis revealed that these genes are not uniformly regulated in response to the change of growth temperature. In addition, all the LOT genes, except for LOT1/FBA1, were induced by a low concentration of cycloheximide. The data indicate that multiple mechanisms, including translational functionality may be involved in the regulation of LOT gene expression in yeast.