Modulation of the complex regulatory network for methionine biosynthesis in fungi

In this study, C. albicans regulates its methionine biosynthetic pathways using the transcription factors Met4 and Cbf1. This circuitry appears more complex than that of filamentous fungi, which use orthologs of the Met4 transcription factor, but lack versions of Cbf1, but is considerably less complex than that of S. cerevisiae, which 2 requires two transcription complexes, involving Cbf1 and Met31/32 as DNA binding modules, and Met4 and the Met4 ortholog Met28 as co-activators, to regulate Met biosynthesis. Although C. albicans contains Met31/32 and Met28 orthologs, they do not appear to be linked to regulation of the methionine circuit. Thus, the phylogenetic progression from filamentous fungi to S. cerevisiae is characterized by increasing complexity of the regulators, although the structural elements of the pathways are fundamentally the same. Overall design: Liquid cultures of all strains were adjusted to OD600 at 0.8 in 10 mL liquid YPD medium and incubated at 30 degrees with shaking at 220 rpm. We conduted RNAseq profiling for 2 replicates.