Wakabayashi Junko, Yomogida Kentaro, Nakajima Osamu, Yoh Keigyou, Takahashi Satoru, Engel James Douglas, Ohneda Kinuko, Yamamoto Masayuki
Centre for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8577, Japan.
Genes Cells. 2003 Jul;8(7):619-30. doi: 10.1046/j.1365-2443.2003.00658.x.
The erythroid transcription factor GATA-1 is also expressed in Sertoli cells of the testis. The testicular expression of GATA-1 is regulated in a developmental and spermatogenic stage-specific manner. To further clarify the regulatory mechanisms of testicular GATA-1 gene expression, we carried out transgenic reporter gene expression analyses.
We found that GATA-1 expression in Sertoli cells is markedly decreased concomitant with the emergence of elongated spermatids in the seminiferous tubules. Transgenic reporter mouse analyses revealed that a 15 kb GATA-1 genomic region is sufficient to recapitulate the gene expression profile in Sertoli cells. While the GATA-1 haematopoietic enhancer and the proximal first exon are included within the 15 kb genomic region, these regulatory elements are not essential for GATA-1 expression in Sertoli cells. Further analyses using deletion constructs revealed that a 1.5 kb region 5' to the GATA-1 haematopoietic enhancer is essential for gene expression in Sertoli cells and this region is referred to as the GATA-1 testis activation region.
These results thus demonstrated that the GATA-1 testis activation region is essential for Sertoli cell-specific expression of GATA-1 gene. The 15 kb genomic region is applicable and useful for the expression vector system specific for adult Sertoli cells in stage VII to IX.
红系转录因子GATA-1也在睾丸的支持细胞中表达。GATA-1在睾丸中的表达以发育和生精阶段特异性的方式受到调控。为了进一步阐明睾丸GATA-1基因表达的调控机制，我们进行了转基因报告基因表达分析。
我们发现，随着生精小管中长形精子细胞的出现，支持细胞中GATA-1的表达显著降低。转基因报告小鼠分析显示，一个15 kb的GATA-1基因组区域足以重现支持细胞中的基因表达谱。虽然15 kb基因组区域包含GATA-1造血增强子和近端第一个外显子，但这些调控元件对于支持细胞中GATA-1的表达并非必需。使用缺失构建体的进一步分析表明，GATA-1造血增强子5'端的一个1.5 kb区域对于支持细胞中的基因表达至关重要，该区域被称为GATA-1睾丸激活区域。
这些结果因此证明，GATA-1睾丸激活区域对于GATA-1基因在支持细胞中的特异性表达至关重要。15 kb基因组区域适用于并有助于构建针对VII至IX期成年支持细胞的表达载体系统。
