Phenotype Image Detail

Image

Caption

Ablation of Kdm3a (Jmjd1a) arrests spermiogenesis and causes apoptosis of developing germ cells. A, Kdm3a deficiency blocked spermiogenesis at spermatid-elongating stages. Testis sections were prepared from 12-week-old wild-type (WT) and Kdm3a^tm1Jxu/Kdm3a^tm1Jxu (KO) mice and stained with periodic acid-Schiff and hematoxylin. The stages of seminiferous epithelium are indicated from I to XII. Note the abnormal head morphologies of elongating spermatids at stages X-XII and stages I-IV and the drastically reduced number of elongated spermatids at stages X-VII in KO testes (green boxes). Sg, spermatogonia; Pl, preleptotene; L, leptotene; Z, zygotene; P, pachytene; 2nd, secondary spermatocyte; RS, round spermatid; ES, elongating spermatid; SC, Sertoli cell; LC, Leydig cell. B, toluidine blue-stained semi-thin sections of WT and KO mouse testes. Developmental steps of spermatids are indicated. acr, acrosome; DS, dorsal side; VS, ventral side. C, detection of apoptotic cells in the testis sections of 12-week-old WT and KO mice by terminal deoxynucleotidyltransferase nick end-labeling assay. Apoptotic cells exhibit brown nuclei in this assay. The lower panels are the enlarged pictures of the boxed regions in the upper panels. The asterisk indicates the small apoptotic nuclei of the elongating spermatids. D, quantitative analysis of apoptotic germ cells in the seminiferous epithelium of WT and KO testes. Three 12-week-old mice per genotype group and two sections per testis were analyzed. Apoptotic cells in group a (pre-pachytene germ cells), group b (pachytene, diplotene and secondary spermatocytes), and group c (spermatids) were counted and recorded separately. Data are presented as the average number (No.) of apoptotic cells per cross-sectioned seminiferous tubule. The Total bar graphs represent the sum of groups a-c. *, p<0.05 by unpaired t test.

Copyright

This image is from Liu Z, J Biol Chem 2010 Jan 22;285(4):2758-70 and is displayed with the permission of the American Society for Biochemistry and Molecular Biology who owns the Copyright. Full text from JBC. J:159956

Associated Alleles

Symbol	Name
Kdm3a^tm1Jxu	lysine (K)-specific demethylase 3A; targeted mutation 1, Jianming Xu

Associated Genotypes

Allelic Composition	Genetic Background
Kdm3a^tm1Jxu/Kdm3a^tm1Jxu	involves: 129S6/SvEvTac * C57BL/6