Transcriptional Regulation in Aspergillus
Tetsuo Kobayashi and Masashi Kato
from: Aspergillus: Molecular Biology and Genomics (Edited by: Masayuki Machida and Katsuya Gomi). Caister Academic Press, U.K. (2010)
Filamentous fungi utilize a variety of organic carbon sources and inorganic/organic nitrogen sources in natural environments. The recently completed genome sequencing of several Aspergillus species reveals that the species in this genus, A. oryzae in particular, have numerous metabolic genes, including those for enzymes involved in the degradation of complex polymers such as carbohydrates and proteins. The existence of such an array of metabolic genes confirms the immense historical contribution of Aspergillus in fermentation, food, and enzyme industries as a source of metabolites and enzymes. In general, genes involved in the degradation of complex polymers, catabolism, and biosynthesis of metabolites are regulated by the availability of carbon and nitrogen sources. As can be expected from the vast number of metabolic genes, which suggests the genus? ability to utilize a number of complex polymers and monomers in nature, it possesses a large number of transcription factors, especially those with Zn(II)2Cys6 DNA binding motif, a characteristic feature of Aspergillus. In this chapter, we first overview the organization of these transcription factors. Next, we describe several mechanisms of transcriptional regulation with special emphasis on the regulation of plant polysaccharide-degrading enzymes and the newly discovered physiological role of the Hap complex. Finally, we list the known Aspergillus transcription factors with brief descriptions read more ...