CPG-free gene for a new secreted reporter protein
A synthetic gene devoid of CpG nucleotide derived by genetic engineering from copepod luciferases genes that code for a new secreted luciferase with a strong bioluminescent signal. This gene display advantageous properties to be used as a reporter genes in cell based assays.
1. An isolated nucleic acid molecule, the nucleic acid encoding a preprotein comprising:
a signal peptide; and
a protein having luciferase activity,
wherein, said nucleic acid molecule is devoid of CpG, and said protein having luciferase activity comprises an amino acid sequence having at least 95% identity to the amino acid sequence set forth as SEQ ID NO: 3.
2. The isolated nucleic acid molecule according to claim 1 , comprising the nucleic acid sequence set forth as SEQ ID NO: 1.
3. The isolated nucleic acid molecule according to claim 1 , wherein said protein having luciferase activity comprises the amino acid sequence having at least 95% identity to the amino acid sequence set forth as SEQ ID NO: 3 when the said protein is secreted from cells.
4. An expression vector, comprising the nucleic acid molecule according to claim 1 operatively linked to a promoter.
5. The expression vector according to claim 4 , wherein the promoter is devoid of CpG.
6. The expression vector according to claim 4 , wherein the promoter is an interferon inducible promoter.
7. The expression vector according to claim 4 , wherein the promoter is inducible by an alpha interferon, a beta interferon or a lambda interferon.
8. The expression vector according to claim 4 , wherein the promoter is an IL28 inducible promoter.
9. An isolated cell transformed with the nucleic acid molecule according to claim 1 .
10. The cell according to claim 9 , wherein the protein encoded by said nucleic acid molecule is secreted by the cell.
11. The cell according to claim 9 further comprising a reporter gene.
12. The cell according to claim 11 , wherein the reporter gene is a secreted embryonic alkaline phosphatase (SEAP) reporter gene.
13. The cell according to claim 12 , wherein the reporter gene is devoid of CpG.
14. A kit comprising:
the nucleic acid molecule according to claim 1 , an expression vector comprising the nucleic acid molecule, or an isolated cell transformed with the nucleic acid molecule or an expression vector comprising the nucleic acid molecule, and
a substrate of the protein having luciferase activity encoded by the nucleic acid molecule.
15. The kit according to claim 14 , wherein the nucleic acid molecule comprises the nucleic acid sequence set forth as SEQ ID NO: 1.
16. An isolated cell transformed with the expression vector according to claim 4 .
17. The isolated nucleic acid molecule according to claim 1 , wherein said protein having luciferase activity comprises an amino acid sequence having at least 98% identity to the amino acid sequence set forth as SEQ ID NO: 3.
18. The isolated nucleic acid molecule according to claim 1 , wherein said protein having luciferase activity comprises the amino acid sequence set forth as SEQ ID NO: 3.
19. The isolated nucleic acid molecule according to claim 1 , wherein the signal peptide comprises the sequence of amino acids 1-17 of SEQ ID NO: 2.
20. The isolated nucleic acid molecule according to claim 1 , wherein said preprotein comprises the amino acid sequence set forth as SEQ ID NO: 2.