Genes responsive to the addition of spermidine or spermine to a polyamine-deficient Saccharomyces cerevisiae mutant

The naturally occurring polyamines putrescine, spermidine or spermine are ubiquitous in all cells. Although polyamines have prominent regulatory roles in cell division and growth, precise molecular and cellular functions are not well established in vivo. In this work we have performed a microarray experiment in a polyamine mutant (delta-spe3 delta-fms1) strain to investigate the responsiveness of yeast genes to supplementation with spermidine and spermine. Expression analysis identified genes responsive to the addition of either excess spermidine (10-5 M) or spermine (10-5 M) compared to a control culture containing 10-8 M spermidine. 247 genes were up-regulated >2-fold, and 11 genes were up-regulated more than 10-fold after spermidine addition. Functional categorization of the genes showed induction of transport related genes, and genes involved in methionine, arginine, lysine, NAD and biotin biosynthesis. 268 genes were down-regulated more than 2-fold, and 6 genes were down-regulated more than 8-fold after spermidine addition. A majority of the down-regulated genes are involved in nucleic acid metabolism and various stress responses. In contrast, only few genes (18) were significantly responsive to spermine. Thus, results from global gene expression profiling demonstrate a more major role for spermidine in modulating gene expression in yeast than spermine.

13

Chattopadhyay MK, Chen W, Poy G, Cam M, Stiles D, Tabor H