Targeted disruption of Reg gene : A new animal model of diabetes and pancreatitis.

1.将Reg I基因外显子2-3突变为新霉素抗性基因的突变型Reg I基因电穿孔于ES细胞，获得了Reg I基因突变的ES细胞克隆。雄性嵌合体将突变等位基因传递给后代。异种小鼠表面上是正常的，并且产生与突变的Reg I位点同源的小鼠。2. Reg I缺陷小鼠在包括胰腺β细胞在内的各种组织中没有表现出形态学改变。Reg I缺陷小鼠的体重、血糖和血清胰岛素水平与对照组小鼠基本相同。3.金硫葡萄糖处理诱导对照组小鼠肥胖伴胰岛β细胞增生。金硫葡萄糖处理的Reg I缺陷小鼠的胰岛明显小于对照组，表明Reg I缺陷小鼠的胰岛响应成年期β细胞增殖的需求具有较低的增殖活性。因此，很有可能作为 ...更多信息 结论：Reg I基因缺陷小鼠在肥胖时易发生非胰岛素依赖性糖尿病（NIDDM），是研究肥胖时NIDDM发生的良好模型。4.在乙硫氨酸诱导的慢性胰腺炎模型中，Reg I基因缺陷小鼠发生重症胰腺炎，且体重低于对照组。这一结果表明，Reg I参与了慢性胰腺炎的抵抗，Reg I缺陷小鼠是一种新的慢性胰腺炎模型。（I、II和III型），所有的Reg基因都定位在6C/D染色体的相邻位点上。6.我们检测了Reg家族其他成员的表达通过北方印迹分析小鼠胰腺中的Reg II、Reg III α、Reg III β和Reg III γ的表达，发现Reg I缺陷小鼠中Reg III α和Reg III γ的表达增加，提示Reg I的某些功能可能通过剩余Reg家族的表达增加而得到补偿。为了阐明这种可能性，我们现在正在培育所有Reg家族基因都有缺陷的突变小鼠。少

1.To generate mutant mice lacking Reg I gene, the mutated Reg I gene, in which exon 2-3 was replaced by neomycin resistant gene, was electroporated in ES cells, and an ES cell clone mutated the Reg I allele was obtained. A male chimera transmitted the mutant allele to its offspring. Heterogous mice were apparently normal, and gave birth to mice homologous for mutant Reg I locus.2.Reg I deficient mice showed no morphological changes in various tissues including pancreatic beta cells. Body weight, blood glucose and serum insulin levels in Reg I-deficient mice were almost the same as those in control mice.3.Aurothioglucose treatment induced obesity with hyperplasia of islet beta-cells in control mice. The islets in aurothioglucose-treated Reg I-deficient mice were significantly smaller than those of control, indicating that islets of Reg I-deficient mice have lower proliferation activity in response to a demand of beta-cell proliferation in adulthood. Therefore, it is quite possible to as … More sume that Reg I-deficient mice easily develop non-insulin dependent diabetes mellitus (NIDDM) when they become obese and be a good model for studying development of NIDDM in obesity.4.In the ethionine-induced chronic pancreatitis model, Reg I-deficient mice developed severe pancreatitis and the body weight of the mutant mice was lower than that of control mice. This result suggests that Reg I is involved in resistance of chronic pancreatitis and that Reg I-deficient mice is a new model of chronic pancreatitis.We revealed that all the mouse Reg genes constitute a multigene family, Reg family, which consists of three subtypes (type I,II and III), and that all the Reg genes assigned to the adjacent site of chromosome 6C/D.6.We examined expression of the other members of Reg family (Reg II,Reg IIIalpha, RegIIIbeta and Reg IIIgamma) in mouse pancreas by Northern blot analyzes, and revealed that expressions of Reg IIIalpha and Reg IIIgamma were increased in Reg I-deficient mice, suggesting a possibility that some functions of Reg I were compensated by the increased expression of remnant Reg family. To clarify this possibility, we are now generating mutant mice deficient in all the Reg family genes. Less