Construction of a plasmid for heterologous protein expression with a constitutive promoter in Trichoderma reesei

•A new binary expression vector with rp2 promoter was constructed.•GFP fusion protein expression showed strong green fluorescence in T. reesei.•Heterologus protein expression of bgla from A. niger was successfully expressed and improved in T. reesei.

Trichoderma reesei is widely used as a host for homologus and heterologus protein expression because of its well-known capability of protein secretion, especially cellulases secretion. In this study, a binary vector which could be used for protein expression was constructed with a constitutive promoter of rp2 gene. This vector contained the expression cassette Prp2-target gene-Trp2 and hygromycin B selection marker based on pCAMBIA1300 for T-DNA random insertion. The feasibility of the promoter was determined by eGFP (enhanced green fluorescence protein) expression in T. reesei. For heterologus protein expression, the expression of bgla from Aspergillus niger in the transformant was 3 folds higher than that of the wild type strain. The results demonstrate that this constitutive promoter could be applied for protein expression and thus this protein express system may contribute to the industrial protein production.