Patent ID: 7820384

Claim:
A method for enhancing expression levels of a protein of interest in a host cell comprising i) operably linking a nucleic acid sequence encoding a ubiquitin like molecule (UBL) molecule selected from the group consisting of RUB, HUB, APG8, APG12, URM1, and ISG15 to a nucleic acid sequence encoding said protein of interest thereby generating a construct encoding a fusion protein, wherein the carboxy terminus of said UBL molecule is directly attached to the amino terminus of said protein of interest in said fusion protein, and wherein the carboxy terminal amino acids of said related-to ubiquitin (RUB), homologous-to-ubiquitin (HUB), autophagy 8 (APG8), autophagy 12 (APG12), ubiquitin-related modifier 1 (URM1), and interferon stimulated gene 15 (ISG15) are Gly-Gly, Tyr-Tyr, Phe-Gly, Phe-Gly, Gly-Gly, and Gly-Gly, respectively; and ii) introducing said nucleic acid into said host cell, whereby the presence of said UBL molecule in said fusion protein increases the expression level of said protein of interest in said host cell.