Establishment of animal models for pharmaceutical experiment in polycystic kidney disease (PKD)

常染色体显性遗传性多囊肾病(ADPKD)是一种最常见的人类遗传性肾脏疾病，突变于PKD1或PKD2基因。我们计划用小鼠和小鱼Medaka建立多囊肾病药物实验的动物模型。首先，将PKD1基因敲除的异种小鼠(PKD1^&lt；+/-&gt；)与端粒酶缺乏症小鼠杂交。由于基因组的不稳定性，端粒缩短会导致频繁的体细胞突变。虽然PKD1^&lt；+/-&gt；+/-&gt；+/-&gt；(同种)小鼠与PKD1^&lt；+/-&gt；(异种)小鼠相比，似乎显示了早期的囊性发生，但在我们的实验中并没有产生像人类ADPKD；+/-&gt；的多囊肾。除带有EF-1α启动子的转基因菌株(EF-1α-A-EGFP-PKD2ΔC)外，还将一株转录因子Δ(EF-1α-A-TTA)和一株青冈PKD2基因缺失突变株与Tet-on载体杂交，获得了另一株转基因菌株(Tet-on EGFP-PKD2 PKD2)。在EF-1α启动子株的肾脏中观察到不同数量的包囊。此外，四个月后的Tet-on菌株显示多囊肾类似于人类ADPKD。这些结果表明，青竹PKD2基因的一个缺失突变体以显性-负性方式抑制固有的PKD2基因。在未来，我们希望这种转基因青竹能够成为多囊肾病药物实验的动物模型。

Autosomal dominant polycystic kidney disease (ADPKD) is a most common human hereditary renal disease mutated in either PKD1 or PKD2 gene. We planned to generate animal models for pharmaceutical experiment in polycystic kidney disease using mice and small fish, medaka.First, Pkd1 knockout hetero mice (Pkd1^<+/->) were intercrossed with telomerase-deficiency mice. Telomere shortening could lead frequent somatic mutation because of genome instability. Although early cystogenesis seemed to be indicated in Pkd1^<+/->/Terc^<+/-> (homo) mice compared to Pkd1^<+/->/Terc^<+/-> (hetero) mice, polycystic kidneys like human ADPKD were not generated in our experiment.Second, we generated transgenic medaka carrying a deletion mutant of medaka Pkd2 cDNA. Beside the transgenic strain with EF-1α promotor (EF-1α-A-EGFP-pkd2ΔC) strains, other strain (Tet-On EGFP-pkd2ΔC strain) was obtained by mating one strain of transcriptional factor rtTA (EF-1α-A-tTA) and one strain of the deletion mutant of medaka Pkd2 gene with Tet-on vector. Various number of cysts were observed in the kidneys of EF-1α promotor strains. Furthermore, Tet-On strains after four months revealed polycystic kidneys resembled to human ADPKD. These results suggest that a deletion mutant of medaka Pkd2 gene inhibit intrinsic Pkd2 gene in a dominant-negative manner. In the future, we hope that this transgenic medaka could be an animal model for pharmaceutical experiment in polycystic kidney disease.