Tetracycline-controlled (TetON) gene expression system for the smut fungus .

is a biotrophic phytopathogenic fungus that causes corn smut disease. As a well-established model system, is genetically fully accessible with large omics datasets available and subject to various biological questions ranging from DNA-repair, RNA-transport, and protein secretion to disease biology. For many genetic approaches, tight control of transgene regulation is important. Here we established an optimised version of the Tetracycline-ON (TetON) system for . We demonstrate the Tetracycline concentration-dependent expression of fluorescent protein transgenes and the system's suitability for the induced expression of the toxic protein . The Golden Gate compatible vector system contains a native minimal promoter from the encoding gene, with ten copies of the tet-regulated operator (tetO) and a codon optimised Tet-repressor (tetR*) which is translationally fused to the native transcriptional corepressor Mql1 (UMAG_05501). The metabolism-independent transcriptional regulator system is functional both, in liquid culture as well as on solid media in the presence of the inducer and can become a useful tool for toxin-antitoxin studies, identification of antifungal proteins, and to study functions of toxic gene products in .