Keller S A, Jones J M, Boyle A, Barrow L L, Killen P D, Green D G, Kapousta N V, Hitchcock P F, Swank R T, Meisler M H
Department of Human Genetics, University of Michigan, Ann Arbor 48109-0618.
Genomics. 1994 Sep 15;23(2):309-20. doi: 10.1006/geno.1994.1506.
The semidominant mutation Krd (kidney and retinal defects) was identified in transgenic line Tg8052. Krd/+ mice have a high incidence of kidney defects including aplastic, hypoplastic, and cystic kidneys. Retinal defects in Krd/+ mice include abnormal electroretinograms and a reduction of cell numbers that is most extreme in the inner cell and ganglion layers. Viability of Krd/+ mice is strongly influenced by genetic background, and growth retardation is observed in young animals. Homozygosity results in early embryonic lethality. Fluorescence in situ hybridization of a transgene-specific probe localized the insertion site to the distal region of mouse Chromosome 19. The sequence of the insertion site revealed transgene insertion into a LINE element with deletion of a single nucleotide from the 3' terminus of the transgene. A polymorphic microsatellite, D19Umi1, was identified in a junction clone and mapped in several large crosses. D19Umi1 is located 1.7 +/- 1.0 cM distal to Pax2, which encodes a paired type transcription factor expressed in embryonic kidney and eye. Deletion of Pax2 from the transgenic chromosome was demonstrated by Southern analysis of genomic DNA from (Krd/+ x SPRET/Ei)F1 mice. Additional genetic and molecular data are consistent with an approximately 7-cM deletion that includes the loci stearoyl CoA desaturase (Scd1), pale ear (ep), D19Mit17, D19Mit24, D19Mit27, D19Mit11, and Pax2. This deletion, Del(19)TgN8052Mm, will be useful for genetic and functional studies of this region of mouse Chromosome 19.
在转基因系Tg8052中鉴定出半显性突变Krd（肾脏和视网膜缺陷）。Krd/+小鼠出现肾脏缺陷的发生率很高，包括肾发育不全、发育不良和多囊肾。Krd/+小鼠的视网膜缺陷包括异常视网膜电图以及细胞数量减少，这在内侧细胞层和神经节层最为明显。Krd/+小鼠的生存能力受到遗传背景的强烈影响，并且在幼龄动物中观察到生长迟缓。纯合子会导致早期胚胎致死。用转基因特异性探针进行荧光原位杂交，将插入位点定位到小鼠19号染色体的远端区域。插入位点的序列显示转基因插入到一个LINE元件中，并且从转基因的3'末端缺失了一个单核苷酸。在一个连接克隆中鉴定出一个多态性微卫星D19Umi1，并在几个大的杂交组合中进行了定位。D19Umi1位于Pax2的远端1.7±1.0 cM处，Pax2编码一种在胚胎肾脏和眼睛中表达的配对型转录因子。通过对(Krd/+×SPRET/Ei)F1小鼠的基因组DNA进行Southern分析，证实了转基因染色体上Pax2的缺失。其他遗传和分子数据与一个约7-cM的缺失一致，该缺失包括硬脂酰辅酶A去饱和酶(Scd1)、淡耳(ep)、D19Mit17、D19Mit24、D19Mit27、D19Mit11和Pax2等基因座。这种缺失，Del(19)TgN8052Mm，将有助于对小鼠19号染色体这个区域进行遗传和功能研究。
