Mori C, Nakamura N, Dix D J, Fujioka M, Nakagawa S, Shiota K, Eddy E M
Department of Anatomy and Developmental Biology, Faculty of Medicine, Kyoto University, Japan.
Dev Dyn. 1997 Jan;208(1):125-36. doi: 10.1002/(SICI)1097-0177(199701)208:1<125::AID-AJA12>3.0.CO;2-5.
The present study examined the occurrence of apoptotic cell death in the testis of wild-type mice from postnatal days 3 to 26 and in juvenile Hsp 70-2 knockout mice. Adult Hsp 70-2 knockout males are infertile and lack spermatids and spermatozoa (Dix et al. [1996a] Proc. Natl. Acad. Sci. U.S.A. 93:3264-3268). To identify the cell types undergoing apoptosis, we also examined the relationship between the occurrence of apoptotic cell death and the expression pattern of the Hsp 70-2 gene product (heat-shock protein 70-2 [HSP70-2]; marker for spermatocytes and spermatids), germ cell nuclear antigen 1 (GCNA1;marker for spermatogonia and spermatocytes), and vimentin (marker for Sertoli cells). This study shows that during postnatal development of the wildtype mouse testis (1) the percentage of apoptotic cell death detected by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method is higher in mice from days 8 to 22 than in younger or older mice, (2) the majority of apoptotic cells are spermatogonia and less frequently are spermatocytes, and (3) the degenerative cell death of spermatogonia and primary spermatocytes involves apoptosis with fragmentation of DNA. The analysis of apoptotic cell death in the testes of juvenile Hsp 70-2 knockout mice showed an additional increased level of apoptosis at day 17, during the first wave of spermatogenesis, in pachytene spermatocytes.
本研究检测了野生型小鼠出生后第3天至26天睾丸中凋亡细胞死亡的发生情况，以及幼年热休克蛋白70-2（Hsp 70-2）基因敲除小鼠睾丸中凋亡细胞死亡的发生情况。成年Hsp 70-2基因敲除雄性小鼠不育，缺乏精子细胞和精子（Dix等人，[1996a]美国国家科学院院刊93:3264 - 3268）。为了确定发生凋亡的细胞类型，我们还检测了凋亡细胞死亡的发生情况与Hsp 70-2基因产物（热休克蛋白70-2 [HSP70-2]；精母细胞和精子细胞的标志物）、生殖细胞核抗原1（GCNA1；精原细胞和精母细胞的标志物）以及波形蛋白（支持细胞的标志物）表达模式之间的关系。本研究表明，在野生型小鼠睾丸出生后的发育过程中：（1）通过末端脱氧核苷酸转移酶介导的dUTP生物素缺口末端标记（TUNEL）法检测到的凋亡细胞死亡百分比在8至22日龄的小鼠中高于年幼或年长的小鼠；（2）大多数凋亡细胞是精原细胞，精母细胞较少；（3）精原细胞和初级精母细胞的退行性细胞死亡涉及DNA片段化的凋亡。对幼年Hsp 70-2基因敲除小鼠睾丸中凋亡细胞死亡的分析表明，在精子发生的第一波期间，即第17天，粗线期精母细胞中的凋亡水平额外增加。
