Epithelial-Specific Cre/lox Recombination in the Developing Kidney and Genitourinary Tract

Abstract

Abstract. Ksp-cadherin is a unique, tissue-specific member of the cadherin family of cell adhesion molecules that is expressed in tubular epithelial cells in the kidney and developing genitourinary (GU) tract. It has recently been shown that a 1341-bp fragment of the 5' flanking region containing the Ksp-cadherin gene promoter can recapitulate the complete expression pattern of the gene in the developing kidney and GU tract. Similar to the endogenous Ksp-cadherin gene, transgenes containing 1341 bp of the 5' flanking region are expressed in developing nephrons, ureteric bud, mesonephric tubules, Wolffian duct, and Müllerian duct. In adult mice, the expression is restricted to renal tubules. In the current study, Ksp1.3/Cre transgenic mice carrying 1329 bp of the Kspcadherin 5' flanking region linked to the Cre recombinase gene were produced. Adult transgenic mice expressed Cre recombinase in renal tubules, especially collecting ducts and thick ascending limbs of Henle's loops. Transgenic embryos expressed Cre recombinase in the branching ureteric bud, developing renal tubules, and sex ducts. Ksp1.3/Cre transgenic mice were crossed with mice carrying a lacZ reporter gene that is activated by Cre/lox-mediated genetic recombination. Bitransgenic progeny expressed lacZ exclusively in renal tubules, mesonephric tubules, ureteric bud, developing ureter, and Wolffian duct. These results demonstrate that Ksp1.3/Cre transgenic mice express Cre recombinase exclusively in the kidney and developing GU tract and can mediate epithelialspecific Cre/lox recombination in these tissues. Ksp1.3/Cre transgenic mice should be useful for cell lineage studies and kidney-specific gene targeting.Cre recombinase (cyclization recombination) is a site-specific DNA recombinase from bacteriophage P1 that mediates genetic recombination at specific 34-bp recognition sites (called loxP) without any requirement for accessory proteins or highenergy cofactors (1). Cre-mediated intramolecular recombination between two directly repeated loxP sites flanking a DNA segment results in deletion of the intervening segment, leaving a single loxP site. If two loxP sites are introduced into the genomic DNA flanking an essential exon

Deletion of claudin-10 ( Cldn10 ) in the thick ascending limb impairs paracellular sodium permeability and leads to hypermagnesemia and nephrocalcinosis

“…These exons are present in the splice variants Cldn10a and Cldn10b (9, 17) and their deletion is predicted to result in an premature stop codon in all encoded isoforms. Mice carrying the floxed allele were bred to mice expressing Cre recombinase under the control of the murine kidney-specific cadherin-16 promoter (ksp-cre + ), resulting in recombinase activity in the TAL and more distal nephron segments (19). Mice homozygous for the floxed Cldn10 allele (Cldn10 fl/fl ) and expressing Cre (Cldn10 fl/fl kspcre + ), termed "cKO" herein, were born at normal Mendelian ratio.…”

Deletion of Lkb1 in Renal Tubular Epithelial Cells Leads to CKD by Altering Metabolism

“…53 Lkb1 flox/flox mice were crossed to transgenic mice expressing Cre recombinase under the cadherin 16 promoter (Ksp-Cre). 54 Transgenic mice were identified by genomic PCR analysis using transgene-specific primers. The presence of a WT Lkb1 and a floxed Lkb1 allele was detected using primers Lkb36/Lkb39 and Lkb39/Pcrs5.…”

MicroRNA-21 Aggravates Cyst Growth in a Model of Polycystic Kidney Disease

“…Pkd2 F/F , 48 Pkd1 F/F , 47 Hnf-1b F/F , 49 Kif3a F/F , 50 miR-21 2/2 , 18 CAGmiR-21, 13 Pkhd1/Cre, 51 Ksp/Cre, 52 and Pkd2 WS25/2 53 mice were used in this study and have been previously described. Equal numbers of male and female mice were included in the analyses shown in Figure 3 and Supplemental Figure 5.…”