Improving the production of foreign proteins
The present invention concerns a method for improving the expression levels of proteins, wherein hydrophobin fusion proteins are expressed, thereby inducing the formation of protein bodies, and wherein said hydrophobin fusions are co-expressed with a target protein or with a further fusion of the target protein.
1. A method for improving expression levels of target proteins, comprising; expressing intracellularly in eukaryotic host cells hydrophobin fusion proteins, thereby inducing formation of protein bodies, and co-expressing the hydrophobin fusion protein with a target protein or with a further fusion of the target protein within said protein bodies.
2. The method according to claim 1 , wherein the expression and the formation of the protein bodies takes place in an endoplasmic reticulum of the host cells.
3. The method of claim 1 , wherein the host cells are selected from plant cells, or from insect, mammalian, yeast, or fungal cells.
4. The method of claim 1 , wherein the hydrophobin is acquired from a filamentous fungi, and selected from the group consisting of HFBI, HFBII, HFBIII, SRHI, SC3, and HGFI.
5. The method of claim 1 , wherein the hydrophobin fusion protein is a fusion protein with a hydrophobin and Green Fluorescent Protein (GFP).
6. The method of claim 1 , wherein the target protein is selected from any heterologous protein, originating from bacteria or higher or lower eukaryotes.
7. The method of claim 1 , further comprising, forming a fusion of the target protein before co-expression.
8. The method of claim 7 , further comprising forming a fusion of the target protein with GFP before co-expression.
9. The method of claim 1 , further comprising storing the expressed protein products in the host cells prior to optional subsequent use.
10. The method of claim 1 , wherein the hydrophobin is acquired from a filamentous fungi, and comprises a polypeptide comprising an amino acid sequence having at least 40% similarity at the amino acid sequence level to one of HFBI, HFBII, HFBIII, SRHI, SC3, or HGFI.