TAL effector-mediated DNA modification
Materials and Methods related to gene targeting (e.g., gene targeting with transcription activator-like effector nucleases; “TALENS”) are provided.
1. A nucleic acid molecule encoding a first transcription activator-like (TAL) effector endonuclease monomer, wherein the first TAL effector endonuclease monomer comprises:
(i) a FokI endonuclease domain, and
(ii) a TAL effector domain comprising a plurality of TAL effector repeat sequences, wherein the plurality of TAL effector repeat sequences of the first TAL effector endonuclease monomer, in combination, bind to a first nucleotide sequence in a target DNA sequence in a cell,
wherein the first TAL effector endonuclease monomer is capable of forming a dimer with a second TAL effector endonuclease monomer comprising a FokI endonuclease domain and a TAL effector domain having a plurality of TAL effector repeat sequences that, in combination, bind to a second nucleotide sequence in the target DNA sequence, wherein the dimer is formed between the FokI domain of the first TAL effector endonuclease monomer and the FokI domain of the second TAL effector endonuclease monomer when the TAL effector domain of the first TAL effector endonuclease monomer is bound to the first nucleotide sequence and the TAL effector domain of the second TAL effector endonuclease monomer is bound to the second nucleotide sequence, wherein the first nucleotide sequence and the second nucleotide sequence are different and are separated by a spacer sequence, and wherein the dimer cleaves the target DNA sequence within the cell.
2. The nucleic acid molecule of claim 1 , wherein the target DNA sequence is in a promoter region.
3. A vector comprising the nucleic acid molecule of claim 1 .
4. The vector of claim 3 , wherein the vector is a viral vector.
5. The nucleic acid molecule of claim 1 , wherein the TAL effector domain comprises 15 or more DNA binding repeats.
6. The nucleic acid molecule of claim 1 , wherein each DNA binding repeat comprises a repeat variable-diresidue (RVD) that determines recognition of a base pair in the target DNA sequence, wherein each DNA binding repeat is responsible for recognizing one base pair in the target DNA sequence, and wherein the RVD comprises one or more of:
HD for recognizing C;
NG for recognizing T;
NI for recognizing A;
NN for recognizing G;
NS for recognizing A;
HG for recognizing T;
IG for recognizing T;
NK for recognizing G;
HA for recognizing C;
ND for recognizing C;
HI for recognizing C;
HN for recognizing G; and
NA for recognizing G.
7. The nucleic acid molecule of claim 6 , wherein each DNA binding repeat comprises a RVD that determines recognition of a base pair in the target DNA sequence, wherein each DNA binding repeat is responsible for recognizing one base pair in the target DNA sequence, and wherein the RVD comprises one or more of:
HA for recognizing C;
ND for recognizing C;
HI for recognizing C;
FIN for recognizing G;
NA for recognizing G; and
NK for recognizing G;
and one or more of:
HD for recognizing C;
NG for recognizing T;
NI for recognizing A;
NN for recognizing G or A;
NS for recognizing A or C or G or T;
HG for recognizing T; and
IG for recognizing T.
8. The nucleic acid molecule of claim 1 , wherein the spacer sequence is 12 to 30 nucleotides in length.
9. The nucleic acid molecule of claim 1 , wherein the spacer sequence is 18 nucleotides in length.
10. The nucleic acid molecule of claim 1 , wherein the nucleic acid molecule is an mRNA.
11. The nucleic acid molecule of claim 1 , wherein the nucleic acid molecule is in a vector.