Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Genes Immun. 2013 Sep;14(6):401-6. doi: 10.1038/gene.2013.30. Epub 2013 May 30.
Mechanism of thymic compartmentalization was studied in the transgenic system using the promoter of thymic stromal cotransporter (TSCOT), a cortical thymic epithelium-specific gene. The transgenic 3.1 kb TSCOT (3.1T) and 4.4 kb TSCOT (4.4T) promoters recapitulated the thymic organ and the cortical epithelial cell-specific expression at the newborn stage. However, the 3.1T driving enhanced green fluorescent protein (EGFP; 3.1T-EGFP) or Cre-recombinase (3.1T-CreE) redistributed the expression into the medulla at the adult stages. Two Cre-transgenic lines (3.1T-CreE and 4.4T-CreE), when crossed with the ROSA LacZ or EGFP lines, showed the reporter expression in both the cortex and the medulla. TSCOT promoter activities were also verified in the transient thymic epithelial cell (TEC) population expressing keratin 5 and keratin 8. These indicate that the TSCOT promoter is turned on in the bipotent TEC precursors and regulated in a compartment-specific, developmentally regulated fashion. These transgenic lines provide the useful systems for delineating the specific pathways for TEC lineage development and function.
胸腺区室化机制在使用胸腺基质共转运体 (TSCOT) 启动子的转基因系统中进行了研究，TSCOT 是皮质胸腺上皮细胞特异性基因。转基因 3.1kb TSCOT(3.1T) 和 4.4kb TSCOT(4.4T) 启动子在新生阶段重现了胸腺器官和皮质上皮细胞特异性表达。然而，3.1T 驱动的增强型绿色荧光蛋白 (EGFP; 3.1T-EGFP) 或 Cre 重组酶 (3.1T-CreE) 将表达重新分配到成年期的髓质中。两个 Cre 转基因系 (3.1T-CreE 和 4.4T-CreE)，与 ROSA LacZ 或 EGFP 系杂交时，在皮质和髓质均显示出报告基因表达。TSCOT 启动子活性也在表达角蛋白 5 和角蛋白 8 的短暂性胸腺上皮细胞 (TEC) 群体中得到了验证。这些表明 TSCOT 启动子在双能 TEC 前体中被激活，并以区室特异性、发育调控的方式进行调控。这些转基因系为描绘 TEC 谱系发育和功能的特定途径提供了有用的系统。
