中文摘要：

本文旨在研究Tbx18＋肾脏间质祖细胞分化为输尿管平滑肌细胞的命运及转录因子Tbx18在小鼠输尿管平滑肌发育形成中起到的作用，实验建立Tbx18：Cre／R26REYFP和Tbx18：Cre／R26RLacZ两种谱系示踪系统和Tbx18：Cre／Cre敲除模型，该示踪模型通过CYe重组酶的表达能有效地示踪Tbx18’肾脏间质祖细胞在泌尿系统的发育命运，通过免疫荧光染色和X-gal染色，同时发现Tbx18＋肾脏间质祖细胞可分化为输尿管平滑肌细胞，但不分化为输尿管移行上皮细胞，在Tbx18：Cre／Cre基因突变模型中，泌尿系统出现明显的肾积水和输尿管积水，肾盏、肾盂扩张，输尿管明显缩短和扩张．实验结果揭示，Tbx18＋肾脏间质祖细胞可以分化为输尿管平滑肌细胞，且转录因子Tbx18在哺乳动物输尿管平滑肌的发育中起到重要的作用。

英文摘要：

Here we elucidate the potential of Tbx18 ＋ smooth muscle and the function of T-box transcription mesenchyme progenitors differentiation into ＇ureteral factor Tbx18 in the forming of smooth muscle in the ureter. We present phenotypic characterization of mouse models of genetic fate-mapping systems Tbx18： Cre/R26REYFP and Tbx18： Cre/R26RLacZ double heterozygous, founded by Cre-loxP system. Meanwhile, Tbx18 ：Cre/Cre mutant mice model was also adopted. The double-heterozygous mice through monitoring the expression of Cre effectively revealed Tbx18-1ineage-traced cells in the ureter. We found that Tbx18 ＋ mesenchyme progenitors give rise to most smooth muscle cells in the ureter but not ureteric epithelium ceils in vivo by the immunoflourescence and X-gal staining of the tissue. In the model of Tbx18：Cre/Cre mutant mice, urogenital systerms displayed a prominent hydronephrosis and hydroureter phenotype with a dilation of the pelvicaliceal space and the mutant ureters of sever length reduction. We reveal that Tbx18 ＋ mesenchyme progenitors differentiate into ureteral muscle and Tbx18 plays a key role in the differentiation fate of ureteral smooth muscle cells.