Robustness analysis of HOG pathway related genes in budding yeast

We applied a novel genetic screening method, named “genetic tug-of-war” (gTOW) to estimate the upper limit of gene copy numbers in Saccharomyces cerevisiae. The study involved 29 HOG pathway related genes which included kinases, phosphatases and transcription factors to cover different set of players in the signal transduction system. In addition a phenotypic profiling was conducted in four different growth conditions with three outputs: lag phase, growth phase and efficiency of growth. A number of interesting hits were identified, including PBS2 which had low numbers of gene copies. It will be of interest to expand the study to encompass the entire known signal transduction system in yeast to search for sensitive nodes