Fig. 1

The rad51^sa23805 allele leads to loss of Rad51 protein and causes DNA damage sensitivity. (A) Western blot showing the expression of Rad51 in testes extracts of WT and mutant zebrafish. β-Actin was used as a loading control. (B) Representative Rad51 immunostained embryos derived from a rad51^+/− in-cross. Secondary only (i), Abcam primary (ii), AnaSpec primary (iii). (Magnification, 65×.) (C) Chromosome spreads of 24-hpf WT and mutant embryos treated with 1 µg/mL DEB for 20 h taken using a 100× oil-immersion objective. White arrows indicate characteristic damage (chromosome breaks and radial structures) in response to cross-linking agents (i). Quantification of the damage (ii). Mann–Whitney test, P = 0.0004, n^+/+ = 25, n^−/− = 26. (D) Comparison of the response of 48-hpf WT and mutant embryos to irradiation (i). (Magnification, 15×.) The black arrow indicates the small head and eye phenotype, which is quantified in ii. Two-tailed Fisher’s exact test pooling WT and heterozygotes as control group, P < 0.001, n = 67. (E) Immunostaining for pH2AX in WT and mutant embryos with pictures of representative embryos taken with a 63× water-immersion objective (i) and quantification of foci (ii). White arrows indicate example foci. Two-tailed Student’s t test, P < 0.0001, n^+/+ = 8, n^−/− = 11.