Activates genes required for amino acid biosynthesis and acts as a master transcriptional regulator during amino acid starvation (PubMed:29432178). Binds variations of the DNA sequence 5'-GAT[AC]GC-3' (PubMed:29432178). Translation is induced by amino acid starvation (PubMed:29432178). Translational repression during nutrient-rich conditions is dependent on several uORFs (upstream open reading frames) present in the 5'-UTR of the mRNA; these promote ribosome dissociation (PubMed:29432178). Translational induction occurs in conditions reducing translation machinery efficiency, leading to ribosomes scanning over the uORFs, and increased translation of the mRNA (By similarity). Decreases the mRNA level of genes involved in amino acid biosynthesis (PubMed:29432178). Increases the mRNA level of genes involved in the response to nitrogen starvation, including genes required for the mating response (PubMed:29432178). Decreases vegetative cell population growth rate in low nutrient conditions (PubMed:29432178). Functional homolog of the S. cerevisiae GCN4 and mammalian ATF4 bZIP transcription factors.