Multiway real-time PCR gene expression profiling in yeast Saccharomyces cerevisiae reveals altered transcriptional response of ADH-genes to glucose stimuli
1 TATAA Biocenter, Odinsgatan 28, 411 03 Göteborg, Sweden
2 Stem Cell Center, Lund University, BMC B10, 221 84 Lund, Sweden
3 Deparment of Cell and Molecular Biology, Göteborg University, BOX 462, 405 30 Göteborg, Sweden
4 Department of Analytical Chemistry, University of A Coruna, A Zapateira s/n, E-15071 A Coruna, Spain
5 Center for Applied Scientific Computing, Lawrence Livermore National Laboratory, Box 808, L-365, Livermore, CA 94551, USA
6 MultiD Analyses AB, Odinsgatan 28, 411 03 Göteborg, Sweden
7 Institute of Biotechnology, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4, 142 20, Czech Republic
8 Department of Clinical Neuroscience and Rehabilitation, Institute of Neurosciences and Physiology, Sahlgrenska Academy at Göteborg University, Medicinaregatan 9A, 413 90 Göteborg, Sweden
BMC Genomics 2008, 9:170 doi:10.1186/1471-2164-9-170Published: 16 April 2008
The large sensitivity, high reproducibility and essentially unlimited dynamic range of real-time PCR to measure gene expression in complex samples provides the opportunity for powerful multivariate and multiway studies of biological phenomena. In multiway studies samples are characterized by their expression profiles to monitor changes over time, effect of treatment, drug dosage etc. Here we perform a multiway study of the temporal response of four yeast Saccharomyces cerevisiae strains with different glucose uptake rates upon altered metabolic conditions.
We measured the expression of 18 genes as function of time after addition of glucose to four strains of yeast grown in ethanol. The data are analyzed by matrix-augmented PCA, which is a generalization of PCA for 3-way data, and the results are confirmed by hierarchical clustering and clustering by Kohonen self-organizing map. Our approach identifies gene groups that respond similarly to the change of nutrient, and genes that behave differently in mutant strains. Of particular interest is our finding that ADH4 and ADH6 show a behavior typical of glucose-induced genes, while ADH3 and ADH5 are repressed after glucose addition.
Multiway real-time PCR gene expression profiling is a powerful technique which can be utilized to characterize functions of new genes by, for example, comparing their temporal response after perturbation in different genetic variants of the studied subject. The technique also identifies genes that show perturbed expression in specific strains.