Figure 2

Delayed onset of meiosis in the absence of DNMT3L. Immunofluorescence analysis of testis cross-section from 10 dpp Dnmt3L^+/- and Dnmt3L^-/- mice using an antibody directed against γ-H2AX (green). A) (Top panel – left) Representative staining pattern obtained in Dnmt3L^+/- sections: a majority of tubules contain γ-H2AX positive cells. (Top panel- right) Only a few tubules containing positive cells can be detected in Dnmt3L^-/- sections. Below each panel are the corresponding DAPI (blue) counterstained images. B) Quantification of the number of tubules containing at least one positive γ-H2AX cell in Dnmt3L^+/- and Dnmt3L^-/- testes. The incidence of positive tubules per 100 tubules was determined from six to nine sections per male, with three males per genotype group. Results are presented as means ± SEM.