TDP-43 knock-in mouse model of amyotrophic lateral sclerosis

1. A TDP-43 knock-in mouse model of amyotrophic lateral sclerosis (ALS) whose genome comprises a heterozygous mutation encoding an N390D substitution in the Tardbp (TDP-43) gene, wherein the expression of the TDP-43 protein is elevated in the spinal cord but not in other tissues of the mouse as compared to a wild-type (+/+) mouse, wherein the mouse exhibits ALS-like phenotypes, TDP-43 proteinopathies, and/or motor neuron degeneration.

2. The TDP-43 knock-in mouse of claim 1 , wherein the ALS-like phenotypes comprise kyphosis.

3. The TDP-43 knock-in mouse of claim 1 , wherein the mouse is male.

4. The TDP-43 knock-in mouse of claim 1 , wherein the ALS-like phenotypes comprise motor dysfunction.

5. The TDP-43 knock-in mouse of claim 1 , wherein the ALS-like phenotypes comprise one or more of the following phenotypes:

(a) motor dysfunction,

(b) abnormal hind limb-clasping,

(c) kyphosis,

(d) shorter life span than the wild type, and

(e) weight loss.

6. A body part isolated from the TDP-43 knock-in mouse of claim 1 .

7. The body part of claim 6 , which is selected from the group consisting of a cell, a tissue, and an organ.

8. The TDP-43 knock-in mouse of claim 1 , wherein the substitution is at nucleotide A of position 1168 of the TDP-43 coding sequence.

9. The mouse of claim 8 , wherein the nucleotide A at position 1168 of the TDP-43 gene coding sequence is substituted with the nucleotide G.

10. The TDP-43 knock-in mouse of claim 1 , whose spinal cord exhibits one or more of the following molecular and cellular pathology as compared to the wild type:

(a) an increased total TDP-43 protein at pre-symptomatic and post-symptomatic ages and progressively elevated with age,

(b) an enhanced cleavage of TDP-43,

(c) an increased fraction of insoluble TDP-43/TDP-34/TDP-28,

(d) mislocalization of TDP-43 from nuclei to cytoplasm of spinal cord motor neurons,

(e) accumulation of ubiquitinated TDP-43 proteins in spinal cord motor neurons, and

(f) a loss of spinal cord motor neurons.

11. An embryo that is an offspring of the mouse of claim 1 , wherein the embryo is heterozygous for the mutation.

12. An embryonic stem cell (ESC) isolated from the embryo of claim 11 .

13. An isolated spinal cord motor neuron that is differentiated from the ESC of claim 12 .

14. The isolated spinal cord motor neuron of claim 13 , which exhibits a higher amount of TDP-43 than a wild-type (+/+) spinal cord motor neuron.

15. The isolated spinal cord motor neuron of claim 13 , which exhibits one or more of the following molecular and cellular pathobgy as compared to a wild-type (+/+) motor neuron:

(a) a higher amount of TDP-43,

(b) a greater amount of TDP-43 in the cytosol,

(c) a reduced survival rate, and

(d) a reduced axon length.

16. The embryo of claim 11 , wherein the embryo is an offspring resulting from a cross between the TDP-43 knock-in mouse of claim 1 and a genetically modified mouse whose genome comprises an Hb9:GFP transgene.

17. An ESC isolated from the embryo of claim 16 .

18. An isolated spinal cord motor neuron differentiated from the ESC of claim 17 .

19. A method for identifying a candidate agent for alleviating and/or suppressing ALS-TDP pathogenesis, comprising:

(a) applying a test agent to the isolated spinal cord motor neuron of claim 15 , and

(b) assaying the effect of the test agent on alleviating and/or suppressing at least one of the TDP-43 proteinopathies and motor neuron degeneration as compared to a wild-type (+/+) motor neuron,

wherein alleviation and/or suppression of the at least one of the TDP-43 proteinopathies and motor neuron degeneration as compared to the wild type (+/+) motor neuron is indicative of a candidate agent for alleviating and/or suppressing the ALS-TDP pathogenesis.

20. A method for identifying a candidate agent for alleviating and/or suppressing ALS-TDP pathogenesis, comprising:

(a) administering a test agent to the TDP-43 knock-in mouse of claim 1 and

(b) assaying the effect of the test agent on at least one of the ALS-like phenotypes,

wherein alleviation and/or suppression of the at least one of the ALS-like phenotypes as compared to a control is indicative of a candidate agent for alleviating and/or suppressing ALS-TDP pathogenesis.