Tissue-specific expression of the rat androgen-binding protein/sex hormone-binding globulin gene in transgenic mice.
Tissue-specific expression of the rat androgen-binding protein/sex hormone-binding globulin gene in transgenic mice.
复制标题
转基因小鼠中大鼠雄激素结合蛋白/性激素结合球蛋白基因的组织特异性表达。
DOI：
10.1016/0303-7207(93)90096-3
复制
发表时间：
1993
影响因子：
4.1
通讯作者：
Gordon,JW
中科院分区：
文献类型：
--
作者：
Reventos,J;Sullivan,PM;Joseph,DR;Gordon,JW
睾丸支持细胞产生细胞外雄激素结合蛋白（ABP），高亲和力结合睾酮和双氢睾酮。ABP基因也编码血浆性激素结合球蛋白（SHBG），这是由大多数物种的肝脏产生的。与人类不同，成年大鼠和小鼠不表达SHBG。一个5.5 kb的大鼠基因组DNA片段包含ABP的整个编码区，位于转录起始位点上游1.5 kb。为了帮助鉴定ABP/SHBG基因的启动子和增强子区域，我们开发了表达大鼠基因的转基因小鼠。将5.5 kb的DNA微注射到受精卵原核中，并将其转移到假妊娠雌性的生殖道中。通过Southern杂交鉴定了3个后代为大鼠基因的携带者，并将这些创始人与正常小鼠杂交，建立了杂合转基因系。成年转基因小鼠的Northern blot分析、RNA-PCR和PCR产物测序显示，大鼠ABP mRNA在睾丸中含量极高，但在肝、肾和脑中未检测到大鼠ABP mRNA。引物延伸实验表明，转基因利用了正确的转录子起始位点。这些数据表明，5.5 kb的基因组DNA片段包含一个能够指导睾丸中ABP基因表达的元件。该增强子可用于在转基因动物中将特定基因产物靶向成熟的支持细胞。
The testicular Sertoli cell produces an extracellular androgen-binding protein (ABP) that binds testosterone and dihydrotestosterone with high affinity. The ABP gene also encodes plasma sex hormone-binding globulin (SHBG), which is produced by the liver of most species. Unlike the human, adult rats and mice do not express SHBG. A 5.5-kb rat genomic DNA fragment was found to contain the entire coding region of ABP and 1.5 kb upstream of the transcription start site. To aid in identification of the promoter and enhancer regions of the ABP/SHBG gene, we developed transgenic mice that express the rat gene. The 5.5-kb DNA was microinjected into the pronuclei of fertilized mice ova, which were transferred to the reproductive tract of pseudopregnant females. Three of the offspring were identified as carriers of the rat gene by Southern hybridization and these founders were bred with normal mice to establish heterozygous transgenic lines. Northern blot analysis, RNA-PCR and sequencing of the PCR products from the adult transgenic mice revealed extremely high levels of the rat ABP mRNA in the testis, but no detectable rat ABP mRNA in liver, kidney or brain. Primer extension experiments showed that the correct transcript ion start site is utilized in the transgenes. These data demonstrate that the 5.5-kb genomic DNA fragment contains an element(s) capable of directing ABP gene expression in the testis. This enhancer should prove useful for the targeting of specific gene products to the mature Sertoli cell in transgenic animals.