Novel molecular mechanisms of iron sensing and homeostasis in filamentous fungi

点击翻译按钮获取中文摘要

Iron is essential for numerous cellular processes but toxic in excess. Moreover, adaptation to iron starvation is a crucial virulence determinant of pathogens including fungi. Due to the fundamental differences in the mechanism employed by host and pathogens to maintain iron homeostasis, iron metabolism is an attractive new target for improvement of antifungal therapy and diagnosis of fungal infections. However, a better understanding of the molecular basis of fungal iron homeostasis is required.In various fungi including the most common airborne fungal pathogen Aspergillus fumigatus, the key iron regulator HapX has been shown to be required for adaptation to iron starvation via its interaction with the CCAAT-binding complex (CBC). Recently, we found that HapX is in addition essential for iron resistance, which underlines that HapX senses the cellular iron status to coordinate the transcriptional response.The planned collaborative studies by geneticists, biochemists and structural biologists aim to explore in molecular depth the functions of the HapX/CBC complex as iron sensor, transcriptional repressor and activator, as well as promoter organizer. In vivo and in vitro analyses are combined with structural examinations of the involved protein/protein and protein/DNA complexes to elucidate these novel regulatory mechanisms in eukaryotes.