Molecular and Somatic Cell Genetics Analysis of Metal Metabolism in Cultured Cells

In this chapter we will discuss the use of molecular and somatic cell genetics techniques to define the mechanisms involved in normal and abnormal responses to metals. Although we will discuss specifically the cellular and molecular responses to Cd²⁺, Cu²⁺, and Zn²⁺, the approaches taken could be of general utility. These approaches employ somatic cell genetic techniques to select cells in which given responses are absent, enhanced, or otherwise altered and to construct hybrid cells for complementation analysis of hereditary defects. Further, molecular genetic techniques are utilized to isolate the genes and gene products involved in normal and abnormal states. It will be shown that the use of such tools allows one not only to define some of the molecular species involved in metal uptake, homeostasis, and detoxification, but also to determine which gene products are involved in modulation of the metabolism of one metal by another. In the following sections we will discuss the derivation of cells with altered metal responses, the molecular bases for the responses, and the use of these systems to define factors involved in metal response and metal interactions.