FIGURE 7.

Fbxw24 knockout increased RAD51 and p‐CHK2 foci in female germ cells. (A and B) Immunofluorescence and quantification showed that RAD51 foci significantly increased in the Fbxw24‐KO zygotene or pachytene germ cells. DNA in blue, RAD51 in green, and SYCP3 in red. (C and D) Western blots and quantification show that the RAD51 level significantly increased in the Fbxw24‐KO 16.5 DPC genital ridge. (E) RAD51 antibody immunoprecipitation and UB46 western blots demonstrate that RAD51 can be ubiquitinated, while Fbxw24 knockout substantially reduced RAD51 ubiquitination level. Further, exogenous FBXW24 protein (1 μg) supplementation increased RAD51 ubiquitination level and reduced RAD51 level close to WT. (F and G) Immunofluorescence and quantification showed that the p‐CHK2 foci significantly increased in the Fbxw24‐KO zygotene or pachytene germ cells. DNA in blue, p‐CHK2 in green, SYCP3 in red. (H and I) Western blots and quantification show that the p‐CHK2 level significantly increased in the Fbxw24‐KO 16.5 DPC genital ridge. (J) p‐CHK2 antibody immunoprecipitation and UB46 western blots demonstrate that RAD51 can be ubiquitinated, while Fbxw24 knockout substantially reduced p‐CHK2 ubiquitination level. Further, exogenous FBXW24 protein (1μg) supplementation increased p‐CHK2 ubiquitination level and reduced RAD51 level close to WT. α‐tubulin or GAPDH was used as a loading control. *, p < 0.05; **, p < 0.01. AU, arbitrary unit