Positive nitrogen regulatory protein. Required for the activation of transcription of a number of genes (including the allantoin pathway genes) in response to the replacement of glutamine by glutamate as source of nitrogen. Binds the nitrogen upstream activation sequence of GLN1, the gene encoding glutamine synthetase. URE2 may catalytically inactivate GLN3 in response to an increase in the intracellular concentration of glutamine. the 9aaTAD motif is a transactivation domain present in a large number of yeast and animal transcription factors. Present with 589 molecules/cell in log phase SD medium.