Question

How would you predict that NH4 in the environment affects transcription of the gene for glutamate dehydrogenase? 01. Negative control 2. Induction 3. Positive control 4 Repression

Answer 1

ans GLUTAMATE is an functional amino acid and plays important role in plant nutrition ,metabolism,and signal transdicion ..we can see in some roots gdh (glutamate dehydrogenase )is induced by ammonia .. let us look at one example:

Arabidopsis thaliana plantlets, and parallel studies were carried out on glutamine synthetase Both NADH-GDH and NAD-GDH activities increased during plant development whereas GS activity declined. Leaves deprived of light showed a considerable enhancement of NADH-GDH activity. In roots, both GDH activities were induced by ammonia whereas in leaves nitrogen assimilation was less important. It was demonstrated that the increase in GDH activity was the result of de-novo protein synthesis. High nitrogen levels were first assimilated by NADH-GDH, while GS was actively involved in nitrogen metabolism only when the enzyme was stimulated by a supply of energy, generated by NAD-GDH or by feeding sucrose. When methionine sulfoximine, an inhibitor of GS, was added to the feeding solution, NADH-GDH activity remained unaffected in leaves whereas NAD-GDH was induced