Reprogramming of carbon metabolism by the transcriptional activators AcuK and AcuM in Aspergillus nidulans

Abstract

The ability of fungi to use carbon sources metabolized via the TCA cycle requires gluconeogenesis. In Aspergillus nidulans the AcuK and AcuM transcription factors regulate the expression of the gluconeogenic genes acuF, encoding phosphoenolpyruvate carboxykinase, and acuG, encoding fructose-1,6-bisphosphatase. Expressed proteins containing the AcuK/AcuM N-terminal DNA-binding domains bind together in vitro to motifs containing repeats of CGG separated by seven bases (CCGN7CCG) and the functionality of these sequences was verified in vivo by acuF-lacZ reporter studies. Chromatin immunoprecipitation analysis showed inter-dependent DNA binding of the proteins to the promoters of gluconeogenic g..