Strategy and validation of the conditional deletion of <i>Tardbp</i> gene.

<p>A) To delete exons 2 and 3 in the endogenous <i>Tardbp</i> we used a targeting vector with 6 Kb and 4 Kb homology arms, shown as black bars. The neomycin resistance was used for positive selection in embryonic stem cells and was flanked by two FRT sites to allow its removal upon FLP mediated recombination. A DTA cassette allowed negative selection of ES cells bearing random integration of the targeting vector. Upon homologous recombination in ES cells (Xs) the endogenous gene was replaced with the targeted cassette. FLP mediated recombination generated a conditional knockout where exons 2 and 3 were flanked by loxP sites. B) Southern Blot analysis of control (+/+) and targeted ES clones. A HindIII digest produced fragments of 7.3 Kb for the WT and 9.1 Kb for the targeted allele. C) Confirmation of neomycin cassette excision by PCR amplification.