The N-terminal half of talin2 is sufficient for mouse development and survival.

Using a talin2 gene-trapped embryonic stem cell clone, we have developed a talin2 mutant mouse line that expresses the N-terminal half (1-1295) of talin2 fused with beta-galactosidase. The homozygous mutant mice appear to be normal and healthy. In the testis, talin2 expresses as a shorter form with a unique 30 residues at N-terminus linking to a common C-terminus from 1122 to 2453 of the long form. The resulting talin2 in the mutant testis only contains 204 residues of the wild-type testis talin2. However, it did not seem to affect the morphology of testis or reproduction of male mice. In fact, male and female mutant mice are fertile. Utilizing the expression of talin2(1-1295)/beta-galactosidase fusion protein, we have examined the distribution of talin2 in tissues. In contrast to talin1, talin2 expression is more restricted in tissues and cell types.