Zabludoff S D, Wright W W, Harshman K, Wold B J
Division of Biology, California Institute of Technology, Pasadena 91125, USA.
Oncogene. 1996 Aug 1;13(3):649-53.
The 17q-linked breast and ovarian cancer susceptibility gene (BRCA1) is believed to function as a tumor suppressor gene (Miki et al., 1994). In this report BRCA1 RNA expression has been analysed in adult mouse tissues with detailed attention to its expression in prepuberal and adult testis. Measurements of BRCA1 mRNA levels in highly purified somatic cells of the testis and in staged germ cells showed that high level BRCA1 mRNA expression is limited to the germ cells. Within the germ cell lineage, the high level expression was detected in meiotic cells, specifically pachytene spermatocytes and in post-meiotic round spermatids. This is in contrast to premeiotic germ cells which were found to express little or no BRCA1 mRNA. These observations, considered together with recent data on the expression of BRCA1 in breast epithelium, argues against a function for BRACA1 in early progenitor cells in both tissues and cells attention instead to roles intimately associated with terminal differentiation or with final rounds of cell division.
17号染色体连锁的乳腺癌和卵巢癌易感基因（BRCA1）被认为起着肿瘤抑制基因的作用（Miki等人，1994年）。在本报告中，对成年小鼠组织中的BRCA1 RNA表达进行了分析，并特别关注其在青春期前和成年睾丸中的表达。对睾丸高度纯化的体细胞和分期生殖细胞中BRCA1 mRNA水平的测量表明，高水平的BRCA1 mRNA表达仅限于生殖细胞。在生殖细胞谱系中，在减数分裂细胞中检测到高水平表达，特别是粗线期精母细胞和减数分裂后圆形精子细胞。这与减数分裂前的生殖细胞形成对比，后者被发现很少或不表达BRCA1 mRNA。这些观察结果，结合最近关于BRCA1在乳腺上皮中表达的数据，反对BRACA1在这两种组织和细胞的早期祖细胞中发挥作用，而是关注与终末分化或最后一轮细胞分裂密切相关的作用。
