FIGURE 1.

Generation of Cdk13^tm1a mice. (A) Scheme of Cdk13^tm1a allele. The Cdk13^tm1a allele consists of strong splicing acceptor (SA), β-galactosidase gene (lacZ) and neomycine resistance gene (neo) both with poly A sites (pA), being surrounded by two FRT sites within intron 2, having two and one lox P sites within intron 2 and 4. (B) PCR genotyping from E12.5 embryos using specific primers distinguishing Cdk13^tm1a, mutant (KO, upper bands) and Cdk13⁺, wild-type, allele (WT, lower bands). (C) Brain extracts were prepared from E14.5 embryos of Cdk13^+/+, Cdk13^tm1a/+ and Cdk13^tm1a/tm1a mice and protein levels of Ser2 and Ser5 of RNAPII, CDK13 and γ-catenin (CTNNG) were evaluated by Western blotting. The short and long expositions for CDK13 are presented to demonstrate residual expression of CDK13 in Cdk13^tm1a/tm1a embryos.