The invention relates to expression constructs comprising the coding nucleic acid sequence for a shuttle peptide construct that can be processed by yeast cells. Also disclosed are adequate expression vectors containing such constructs, methods for the recombinant production of target proteins, which are carried out with the aid thereof, hosts transformed therewith, shuttle peptides and nucleic acid sequences coding therefor, nucleic acid sequences that code for such shuttle peptides and are fused with a foreign protein, hydrophobin proteins produced by means of such shuttle peptides, and the use of hydrophobins for coating objects such as leather.