Fig. 1

Construction and transfection of the ETAs. A short flexible linker (GGGGSGGGGS) and activation domain of VP16 (vp16AD) were fused with the C terminus of the natural proteins, ACE2 (aa 1–341), ACE1 (aa 1–733), or XYR1 (aa 1–920). The C-terminal last encoding codon of each natural protein was fused to the linker and then fused to the activation domain of VP16 by Seamless Cloning and Assembly Kit (TransGen, Beijing, China). ETAs were used to replace the natural regulators in T. reesei RUT C30. Transformants T_ACE2VP, T_ACE1VP, and T_XYR1VP were obtained after xylose-induced marker rescue