Construction of mammalian cell lines with indicator genes driven by regulated promoters

The regulation of gene expression is a central feature of cell growth and differentiation. An important question is how information received at the cell surface is ultimately transmitted to the nucleus and how it causes changes in the pattern of gene expression. To study the molecular basis of this process, we have established cell lines carrying marker genes under the control of known regulatory promoter elements. These cell lines are being used to investigate the effects of activating normal cellular second messenger systems or of microinjecting proteins hypothesized to function in signal transduction, such as oncogene products or subunits of enzymes.