The TOR-controlled transcription activators GLN3, RTG1, and RTG3 are regulated in response to intracellular levels of glutamine

• DOI: 10.1073/pnas.102687599
• Publication Date: 2002-07-26T14:46:49Z
• Authors: José L. Crespo; Ted Powers; Brian Fowler; Michael N. Hall
• Keywords: GATA transcription factor

The essential, rapamycin-sensitive TOR kinases regulate a diverse set of cell growth-related readouts in response to nutrients. Thus, the yeast proteins function as nutrient sensors, particular sensors nitrogen and possibly carbon. However, metabolite(s) that acts upstream is unknown. We investigated role glutamine, preferred source key intermediate metabolism, possible regulator TOR. show glutamine synthetase inhibitor l -methionine sulfoximine (MSX) specifically provokes depletion cells. MSX-induced starvation caused nuclear localization activation TOR-inhibited transcription factors GLN3, RTG1, RTG3, all which mediate synthesis. GLN3 required TOR-controlled, type 2A-related phosphatase SIT4. Other TOR-controlled factors, GAT1/NIL1, MSN2, MSN4, an unknown factor involved expression ribosomal protein genes, were not affected by starvation. These findings suggest pathway senses glutamine. Furthermore, affects only subset appears discriminate between different conditions elicit appropriate given condition.