Transcriptional Regulation of the Yeast GMP Synthesis Pathway by Its End Products

摘要: AMP and GMP are synthesized from IMP by specific conserved pathways. In yeast, whereas synthesis coregulated, we found that the pathway is specifically regulated. Transcription of IMD genes, encoding yeast homologs dehydrogenase, was repressed extracellular guanine. Only this first step GDP regulated, since latter steps, encoded GUA1 GUK1 guanine-insensitive. Use mutants affecting metabolism revealed guanine had to be transformed into allow repression genes. gene transcription also strongly activated mycophenolic acid (MPA), a inhibitor dehydrogenase activity. Serial deletions IMD2 promoter presence negative cis-element, required for regulation. Point mutations in response element enhanced expression, making it insensitive MPA. From these data, propose sequence mediates process, which addition, through or derivative, abolished