The regulation of yeast gene expression by multiple control elements.

Abstract

The effective employment of biological systems for production of commercially useful chemicals often requires a thorough understanding of how the desired system is regulated. In the past we have looked to procaryotic systems for models of how control is exerted; they have served us well. However, it is becoming abundantly clear that the procaryotic paradigm does not extend to eucaryotic systems. For these, new models must be developed and new paradigms constructed. My purpose is the development of such a model in the simple eucaryotic microorganism, Saccharomyces cerevisiae. This yeast is perhaps the oldest commercially cultured organism in existence. It is also one of the most well studied genetic systems available. Our model is the metabolism of two main nitrogen sources, allantoin and arginine. We selected two systems instead of one to gain some insight into the spectrum of regulatory mechanisms that operate in eucaryotic cells. Our choice also presents the added opportunity of assessing the means used to integrate the expression of separately controlled, but functionally related genes.