Method of synthesizing a suppressor TRNA, DNA construct and use thereof for producing a protein including a non-natural amino acid
There are provided a DNA construct comprising non-eukaryote-derived suppressor tRNA gene containing no internal promoter functioning in a eukaryotic cell, and a eukaryote-derived or bacteriophage-derived promoter linked at the 5′ end of the tRNA gene, a method for synthesizing a suppressor tRNA by using the DNA construct, and a process for producing a non-natural amino acid-incorporated protein by using the same.
1. A DNA construct comprising a suppressor tRNA gene from a non-eukaryotic origin, wherein said tRNA gene contains no internal promoter sequence, has a eukaryotic promoter linked to the 5′ end of said tRNA gene, and functions in a eukaryotic cell, wherein said tRNA gene is a tRNA gene from an archaebacteria and said eukaryotic promoter is a pol III type III promoter.
2. The DNA construct of claim 1 , wherein said tRNA gene is a pyrrolysine tRNA gene from archaebacteria origin.
3. The DNA construct of claim 1 , further comprising a transcription terminator sequence linked to the 3′ end of said tRNA gene.
4. The DNA construct of claim 1 , wherein said pol III type III promoter is a promoter of a U6 snRNA gene.
5. The DNA construct of claim 4 , wherein said promoter of the U6 snRNA gene has the nucleotide sequence set forth in SEQ ID NO: 3 or a nucleotide sequence that is at least 90% identical thereto, and induces transcription by RNA polymerase III in a mammalian cell.
6. A method of synthesizing a suppressor tRNA comprising expressing the DNA construct of claim 1 in a eukaryotic cell.
7. A recombinant eukaryotic cell that is transformed or transfected by the DNA construct of claim 1 .