Autor: |
Fermi B; Dipartimento di Bioscienze, Università degli Studi di Parma, Parco Area delle Scienze 23/A, 43124, Parma, Italy., Bosio MC; Dipartimento di Bioscienze, Università degli Studi di Parma, Parco Area delle Scienze 23/A, 43124, Parma, Italy.; Dipartimento di Bioscienze, Università degli Studi di Milano, Via Celoria 26, 20133, Milan, Italy., Dieci G; Dipartimento di Bioscienze, Università degli Studi di Parma, Parco Area delle Scienze 23/A, 43124, Parma, Italy. giorgio.dieci@unipr.it. |
Abstrakt: |
In Saccharomyces cerevisiae, the large majority of the genes coding for cytoplasmic ribosomal proteins (RPs) depend on the general regulatory factor Rap1 for their transcription, but a small cohort of them relies on Abf1 regulatory activity. A recent study showed that unlike Rap1, whose association with RP gene promoters is not affected by environmental changes causing RP gene repression/reactivation, Abf1 association with both RP gene and ribosome biogenesis (Ribi) gene promoters dynamically responds to changes in growth conditions. This observation changes the paradigm of general regulatory factors as relatively static DNA-binding proteins constitutively bound to highly active promoters, and point to Abf1, which binds hundreds of non-RPG promoters within the yeast genome, as a possible key regulatory switch in nutrient- and stress-dependent transcriptional modulation. Moreover, the frequent presence of Abf1 binding sites in the promoters of mitochondrial RP genes evokes the possibility that Abf1 might orchestrate still unexplored levels of co-regulation involving growth-related gene networks in yeast cells. |