Characterization Of Wilms Tumor Suppressor Gene Product

Wilms肿瘤抑制基因WT1在10-15%的Wilms肿瘤（一种儿童肾癌）中发生突变，编码一种具有C2H2锌指DNA结合域的转录因子。由于WT1缺失的小鼠胚胎缺乏所有这些器官，因此WT1被认为可以调节对肾脏、性腺、脾脏和肾上腺的启动和分化至关重要的基因的转录。除了Wilms肿瘤外，其他人类综合征和疾病也由WT1基因突变引起，如Danys-Drash综合征和Frasier综合征。使用微阵列表达谱，我们已经确定了许多WT1靶基因，这些基因似乎对肾脏发育很重要。目的基因通过定量RT-PCR、染色质免疫沉淀、启动子报告子测定和wt1阳性肾细胞的表达独立验证。为了研究这些靶点在肾脏发育过程中的生理作用，我们使用体外肾器官培养实验来确定它们对肾脏分化的影响。鉴定靶基因并确定其在发育过程中的作用将为Wilms肿瘤的发展和器官发生提供进一步的见解。

The Wilms tumor suppressor gene WT1, which is mutated in 10-15% of Wilms tumor -- a pediatric kidney cancer -- encodes a transcription factor with C2H2 zinc finger DNA binding domain. WT1 is proposed to regulate transcription of genes that are critical for the initiation and differentiation of kidney, gonad, spleen, and adrenal gland since wt1-null mouse embryos lack all of these organs. In addition to Wilms tumor, other human syndromes and diseases are also caused by mutations in the WT1 gene such as Danys-Drash and Frasier syndromes. Using microarray expression profiling, we have identified a number of WT1 target genes that appears to be important for kidney development. The target genes were independently verified using quantitative RT-PCR, chromatin-immunoprecipitation, promoter-reporter assay and expression in WT1-positive cells in the develping kidneys. To examine the physiological role of these targets during kidney development, we used in vitro kidney organ culture assay to determine their effects on kidney differentiation. Identification of the target genes and defining their role during development will provide further insights to the development of Wilms tumor and organogenesis in general.