Phenotype Image Detail

Image

Caption

Defective meiotic recombination and crossover formation in infertile Setx^tm1.1Mfl/Setx^tm1.1Mfl males. A. Initiation and repair of programmed DNA double strand breaks (DSB) as shown by gammaH2AX staining of spermatocytes spreads of wild-type (WT) and mutant adult mice. At pachytene, gammaH2AX staining is restricted to the XY chromosomes (circle) in WT spermatocytes, whereas some gammaH2AX foci remained on asynapsed autosomes indicating persistence of unrepaired DSB in mutants. Normal gammaH2AX staining of the XY chromosomes (circle) was observed in both WT and mutant pachytene stage spermatocytes. Scale bar, 20 um. XY, sex chromosomes. B. Persistence of Rad51 foci at pachytene stage in mutant spermatocytes indicating the presence of unrepaired DSBs (compare 1 and 2). Scale bar, 20 um. C. Quantitation of Rad51 foci revealed a 6-fold increase in the number of Rad51 foci at pachytene stage in mutant as compared to WT (Student's t-test, n = 50), indicates * p<0.05. D. Formation of chiasmata at pachytene stage in WT spermatocytes as marked by Mlh1 staining. No Mlh1 foci were detected in mutant pachytene cells indicating that crossovers do not occur in the mutants. 1 and 2 represent magnification of autosomes. Scale bar, 20 um. SCP3 or SCP1 were used to identify the meiotic stages. E. Defect in senataxin leads to R-loop structures accumulation in germ cells. Staining with S9.6 antibody (R-loops) on adult spermatocytes revealed an increased formation of R-loops in mutant germ cells. Scale bar, 20 um. F. Number of pachytene spermatocytes showing none-faint, medium, and strong R-loop staining intensities for WT and mutants.

Copyright

This image is from Becherel OJ, PLoS Genet 2013 Apr;9(4):e1003435, and is displayed under the terms of the Creative Commons Attribution 4.0 International License. J:223053

Associated Alleles

Symbol	Name
Setx^tm1.1Mfl	senataxin; targeted mutation 1.1, Martin F Lavin

Associated Genotypes

Allelic Composition	Genetic Background
Setx^tm1.1Mfl/Setx^tm1.1Mfl	Not Specified