Promoter and signal sequence from filamentous fungus can drive recombinant protein production in the yeast Kluyveromyces lactis.

Cross-recognition of promoters from filamentous fungi in yeast can have important consequences towards developing fungal expression systems, especially for the rapid evaluation of their efficacy. A truncated 510bp inducible Trichoderma reesei cellobiohydrolase I (cbh1) promoter was tested for the expression of green fluorescent protein (GFP) in Kluyveromyces lactis after disrupting its native β-galactosidase (lac4) promoter. The efficiency of the CBH1 secretion signal was also evaluated by fusing it to the lac4 promoter of the yeast, which significantly increased the secretion of recombinant protein in K. lactis compared to the native α-mating factor secretion signal. The fungal promoter is demonstrated to have potential to drive heterologous protein production in K. lactis; and the small sized T. reesei cbh1 secretion signal can mediate the protein secretion in K. lactis with high efficiency.