Increased production of secreted proteins by recombinant eukaryotic cells
Described herein are methods for increasing the amount of protein secreted by a cell. In one case, a cell is provided which contains a heterologous nucleic acid encoding a protein having unfolded protein response modulating activity and a heterologous nucleic acid encoding a protein of interest to be secreted. In one case, the protein having unfolded protein response modulating activity is selected from the proteins selected from the group consisting of HAC1, PTC2 and IRE1. The protein of interest can be any secreted protein such as a therapeutic or an industrial enzyme. For example the protein can be selected from the group consisting of lipase, cellulase, endo-glucosidase H, protease, carbohydrase, reductase, oxidase, isomerase, transferase, kinase, phosphatase, alpha-amylase, glucoamylase, lignocellulose hemicellulase, pectinase and ligninase.
1. A cell containing a heterologous yeast or filamentous fungal nucleic acid encoding a protein comprising a DNA binding domain consisting of:
a) at least 95% sequence identity to the DNA binding domain of amino acid sequence of SEQ ID NO: 5; or
b) at least 95% sequence identity to the DNA binding domain of amino acid sequence of SEQ ID NO:19, and
a heterologous nucleic acid encoding a protein of interest to be secreted.
2. The cell of claim 1 wherein said protein of interest is selected from the group consisting of lipase, cellulase, endo-glucosidase H, protease, carbohydrase, reductase, oxidase, isomerase, transferase, kinase, phosphatase, alpha-amylase, glucoamylase, lignocellulose hemicellulase, pectinase and ligninase.
3. The cell of claim 1 , wherein the protein comprising a DNA binding domain is constitutively produced.
4. The cell of claim 1 , wherein the protein comprising a DNA binding domain is encoded by a nucleic acid isolated from a cell selected from the group consisting of Aspergillus, Trichoderma, Saccharomyces, Schizosaccharomyces, Kluyveromyces, Pichia, Hansenula, Fusarium, Neurospora , and Penicillium.
5. The cell of claim 1 , wherein the protein comprising a DNA binding domain is encoded by a nucleic acid isolated from filamentous fungi.
6. The cell of claim 5 , wherein said fungi is Trichoderma reesei.
7. The cell of claim 1 wherein the DNA binding domain of SEQ ID NO:5 comprises amino acid residues 84-147 of SEQ ID NO: 5.
8. The cell of claim 1 , where in the DNA binding domain of SEQ ID NO:19 comprises amino acid residues 45-109 of SEQ ID No:19.