Generation of the wild-type Tsc2 transgenic Eker rat and its effect on renal carcinogenesis.

野生型 Tsc2 转基因 Eker 大鼠的产生及其对肾癌发生的影响。

• 批准号: 08680915
• 负责人: KOBAYASHI Toshiyuki
• 金额: $ 1.54万
• 依托单位: Japanese Foundation for Cancer Research
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08680915/
• 关键词: Eker rat; Hereditary tumoar; Renal cancer; Embryonic lethality; Tsc2 gene; Transgenic rat

We have identified a predisposing germline mutation for the Eker rat hereditary renal carcinoma in the rat homelog of human tuberous sclerosis 2 gene (TSC2). Also we have indentified somatic mutations and deletions on the wild-type Tsc2 allel (second hits) in renal carcinomas and even in preneoplastic lesions fom the Eker rat, indicating that the Tsc2 gene functions as a tumor suppressor. In tahis study, an attempt to suppress phenotypes of the Eker rat, the renal carcinogenesis in heterozygotes for Tsc2mutataion and the embryonic lethality in homozygous Tsc2 mutants, was carried out by introduction of a wild-type Tsc2 transgere. The transgene used here consisted of a wild-type rat Tsc2 cDNA (lacking exons 25 and 31 by alternative splicing events) and genomic DNA,and was driven by Tsc2 promoter. By idntroduction of this transgene, both of renalcarcinogenesis and embryonic lethality were successfully suppressed in the Eker rat. These results are final evidence to define the germline mutataion of Tsc2 gene as the cause of Eker rat phenotypes. Interesltingly, rescued homozygous Tsc2 mdutants developed renal tumors as well as pituitary tumors, which often developed in the Eker draats. In these tumors, the wild-type Tsc2 transgene was somatically deleted, indicating that the initiation of these tumors was caused by loss of Tsc2 function. the transgenic rescue for the Eker rat phenotype established in this study will be a usefull in vivo experimental system to analyze the function of Tsc2 gene and its product, and to elucidate molecular mechanism of tumorigenesis caused gy Tsc2 mdutations.

我们在人类结节性硬化症 2 基因 (TSC2) 的大鼠同源基因中发现了 Eker 大鼠遗传性肾癌的易感种系突变。此外，我们还在肾癌甚至 Eker 大鼠的癌前病变中鉴定出野生型 Tsc2 等位基因（第二次命中）的体细胞突变和缺失，表明 Tsc2 基因具有肿瘤抑制基因的功能。在该研究中，试图通过引入野生型 Tsc2 转基因来抑制 Eker 大鼠的表型、Tsc2 突变杂合子的肾癌发生以及纯合 Tsc2 突变体的胚胎致死率。这里使用的转基因由野生型大鼠 Tsc2 cDNA（由于可变剪接事件缺少外显子 25 和 31）和基因组 DNA 组成，并由 Tsc2 启动子驱动。通过导入该转基因，在Eker大鼠中成功抑制了肾癌发生和胚胎致死率。这些结果是确定 Tsc2 基因种系突变是 Eker 大鼠表型原因的最终证据。有趣的是，被拯救的纯合 Tsc2 突变体会​​发展成肾肿瘤和垂体肿瘤，这些肿瘤通常发生在埃克德拉特（Eker draats）中。在这些肿瘤中，野生型 Tsc2 转基因被体细胞删除，表明这些肿瘤的发生是由 Tsc2 功能丧失引起的。本研究建立的Eker大鼠表型转基因拯救系统将成为分析Tsc2基因及其产物功能、阐明Tsc2突变导致肿瘤发生的分子机制的有用体内实验系统。

项目成果

Kobayashi, T., et al.: "Indentification of a leader exon and a core promoter for the rat tuberous sclecosis 2 (Tsc2) gene and structural comparison with human homolog." Mammalian Genome. 8. 554-558 (1997)

Kobayashi, T. 等人：“大鼠结节性硬化症 2 (Tsc2) 基因的前导外显子和核心启动子的鉴定以及与人类同源物的结构比较。”

Kobayashi,T.,et al.: "Transgenic rescue from embryonic lethality and renal carcinogenesis in the Eker rat model by introduction of a wild-type Tsc2 gene." Proc.Natl.Acad.Sci.USA. 94. 3990-3993 (1997)

Kobayashi,T.,et al.：“通过引入野生型 Tsc2 基因，在 Eker 大鼠模型中进行转基因拯救，避免胚胎致死和肾癌发生。”

Kobayashi, T., et al.: "Transgenic rescue from embryonic lethality and renal carcinogenesis in the Eker rat model by introduction of a wild-type Tsc-gene." Preac.Natl.Acad.Sic.USA. 94. 3990-3993 (1997)

Kobayashi, T. 等人：“通过引入野生型 Tsc 基因，在 Eker 大鼠模型中进行转基因拯救，避免胚胎致死和肾癌发生。”

Kobayashi, T., et al.: "Identification of a leader exon and a core promoter for the rat tuberous sclerous 2(Tsc2)gene and structural comparison with human homolog." Mammalian Genome. 8. 554-558 (1997)

Kobayashi, T. 等人：“大鼠结节性硬化症 2(Tsc2) 基因前导外显子和核心启动子的鉴定以及与人类同源物的结构比较。”

Kobayashi,T.et al.: "Transgenic rescue from embryonic lethality and renal carcinogenesis in the Eker rat model by introduction of a wild-type Tsc2 gene." Proc.Natl.Acad.Sci.USA. 94 (in press). (1997)

Kobayashi,T.et al.：“通过引入野生型 Tsc2 基因，在 Eker 大鼠模型中进行转基因拯救，避免胚胎致死和肾癌发生。”