Phenotype Image Detail

Image

Caption

A and B: Light micrographs of testes (around stage VII-VIII). Sections were stained with toluidine blue. A: Normal spermatogenesis in wild type testis. B: Vacuoles (*) and degenerated symplast-like cells (arrows) were found in Lmtk2^tm1Tya/Lmtk2^tm1Tya testis. C-I: Electron micrographs of wild type (C) and mutant mice (D-I) testes. Sections were stained with lead and uranyl acetate. C: Normal spermiogenesis with healthy round and elongating spermatids in wild type testis. D: In mutant testis, round spermatids appear to be produced normally but gradually show abnormal development in the acrosome (F). E: Elongating spermatids develop abnormally and are eventually engulfed by Sertoli cells (arrows) with residual bodies (*). G and H: Elongated spermatids at step S13-14 in mutant testes, showing varieties of deformations and collapsed components such as acrosome and nucleus in the head (G). Collapsed acrosome (arrows) and vacuoles (*) found in Sertoli cells are indicated (H). I: A few elongated spermatids survived until approximately step 15. Irregular acrosomes (arrows) and condensed nuclei (N) are indicated. The spermatids show electron-dense material with many vesicular structures at the border between the head and tail (double arrow). Middle piece shows relatively well arranged mitochondrial sheath (M) and principal piece region with fibrous sheath (P). A developed round spermatid (r-St) has and irregular acrosome (*), a part of which in shown in Inset. (Inset) A higher magnification image of the rectangular area. Shown are manchette (arrow), irregular acrosome (*), and tail components such as fibrous sheath and outer dense fibers (double arrow; the axoneme is not clearly recognized at this magnification) J and K: Stage matched images of wild type (J) versus mutant testes (K). Periodic acid/Schiff (PAS) staining shows stage XII that can be identified with secondary spermatocytes dividing at meiosis II (*). There are many elongating spermatids with PAS-positive acrosomes in the tubule of wild type testis (J). Few or no elongating spermatids are survived in the tubule of mutant testis (K). A, acrosome; Ag, acrosome granule; BM, basement membrane; Es, elongating or elongated spermatid; M, mitochondria; N, nucleus; P, pachytene spermatocyte; Rs, round spermatid; S, Sertoli cell. Scale bar: A and B, 10um; C, E and I, 2um; Inset, F and H, 1um; G, 0.5um J and K, 10um.

Copyright

This image is from Kawa S, Proc Natl Acad Sci U S A 2006 Dec 19;103(51):19344-9. Copyright 2006 National Academy of Sciences, U.S.A. J:118247

Associated Alleles

Symbol	Name
Lmtk2^tm1Tya	lemur tyrosine kinase 2; targeted mutation 1, Tadashi Yamamoto

Associated Genotypes

Allelic Composition	Genetic Background
Lmtk2^tm1Tya/Lmtk2^tm1Tya	involves: 129P2/OlaHsd * C57BL/6