NCR-sensitive amino acid permeases

To study the specific regulation of the synthesis of NCR-sensitive amino acid transporters, Saccharomyces cerevisiae cells are grown with proline or urea as the sole source of nitrogen, i.e., in the absence of NCR (see section 6.3). 

Taken together, these results show that specific induction of several permease- as well as enzyme-genes in Saccharomyces cerevisiae is a complex mechanism involving distinct combinations of specific and pleiotropic, positive and negative regulatory proteins (Fig. 4). 

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