Vector comprising multiple homologous nucleotide sequences
The invention relates to vectors comprising two or more homologous nucleotide sequences and methods for generating them. The invention concerns substituting bases in the homologous nucleotide sequences with different bases that do not alter the encoded amino acid sequence. The invention allows for the reduction of intramolecular recombination between homologous nucleotide sequences, in particular in mammalian cells. The invention further relates to nucleotide sequences containing substituted bases.
1. A method for generating a stable modified vaccinia Ankara (MVA) virus vector comprising:
providing a vector or vectors containing two nucleotide sequences of at least 800 nucleotides each, encoding proteins with at least 75% identity within a stretch of at least 150 contiguous amino acids;
substituting at least 400 nucleotides in one or both of the nucleotide sequence(s) to generate two divergent sequences;
wherein the 400 substituted nucleotides do not alter the amino acids encoded by the two divergent sequences; and
generating a stable MVA vector comprising the two divergent sequences stably inserted into the MVA genome and that expresses the encoded amino acid sequences,
wherein the two divergent sequences share stretches of identity of no more than 9 contiguous nucleotides;
wherein the two nucleotide sequences encode a full length RSV-F protein and a truncated RSV-F protein.
2. The method of claim 1 , wherein the two divergent sequences comprise the sequences of SEQ ID NO:1 and SEQ ID NO:2.
3. The method of claim 1 , wherein the two divergent sequences encode the amino acid sequences of SEQ ID NO:3 and SEQ ID NO:4.
4. A method for generating a stable modified vaccinia Ankara (MVA) virus vector comprising:
providing two nucleotide sequences of at least 800 nucleotides each, encoding proteins with at least 75% identity within a stretch of at least 150 contiguous amino acids;
substituting at least 400 nucleotides in one or both of the nucleotide sequence(s) to generate two divergent sequences;
wherein the 400 substituted nucleotides do not alter the amino acids encoded by the two divergent sequences; and
generating a stable MVA vector comprising the two divergent sequences stably inserted into the MVA genome and that expresses the encoded amino acid sequences,
wherein the two divergent sequences share stretches of identity of no more than 9 contiguous nucleotides;
wherein the two nucleotide sequences encode a full length RSV-F protein and a truncated RSV-F protein.
5. The method of claim 4 , wherein the two divergent sequences comprise the sequences of SEQ ID NO:1 and SEQ ID NO:2.
6. The method of claim 4 , wherein the two divergent sequences encode the amino acid sequences of SEQ ID NO:3 and SEQ ID NO:4.
7. A method for generating a stable modified vaccinia Ankara (MVA) virus vector comprising
providing first and second nucleotide sequences of at least 800 nucleotides each, encoding proteins with at least 75% identity within a stretch of at least 150 contiguous amino acids;
wherein one of the two nucleotide sequences has at least 400 nucleotides different from the other nucleotide sequence and wherein the different nucleotides do not alter the amino acids encoded by the first and second nucleotide sequences and wherein the two nucleotide sequences share stretches of identity of no more than 9 contiguous identical nucleotides; and
inserting the first and second nucleotide sequences into an MVA vector to generate a stable MVA vector that expresses the encoded amino acid sequences;
wherein the two nucleotide sequences are a full length RSV-F gene and a truncated RSV-F gene.
8. The method of claim 7 , wherein the two divergent sequences comprise the sequences of SEQ ID NO:1 and SEQ ID NO:2.
9. The method of claim 7 , wherein the two divergent sequences encode the amino acid sequences of SEQ ID NO:3 and SEQ ID NO:4.