R cells. Transfected ES cells underwent double-selection with the neomycin analogue G418 (Gibco), at a concentration of 200 mg/ml and with gancyclovir (2 mM). ES clones were screened by Southern blot Nobiletin site analysis using DNA probes external to both the 59 and 39 ends of the Krt7 homology arms. Microinjection of ES cell clones and generation of chimeric mice were performed as described previously [14]. Chimeric male mice were mated with C57BL/6 female mice and germline transmission of the targeted Krt7 allele was confirmed by PCR analysis of the resulting offspring. For continued maintenance of the line, K7 knockout mice were backcrossed onto the C57Bl6 background. Genotyping of K7 knockout mice was performed using the following primers: MedChemExpress Linolenic acid methyl ester forward primer 59 CTA CTG GCC TCA GGA ATC TAG G 39; reverse primer 1 59 AAG AAC CGT GCG ACT GAG 39 and reverse primer 2 59 GAA TAT CAT GGT GGA AAA TGG C 39 to generate PCR products of 743 bp (wildtype allele) and 593 bp (knockout allele). PCR conditions were as follows: 1 cycle at 94uC for 3 minutes followed by 40 cycles of 94uC (30 sec); 58uC (30 sec); 72uC (1 minute) and a final extension cycle of 72uC for 5 minutes.Immunofluorescence MicroscopyMouse tissues (a minimum of 3 mice per genotype) were embedded in OCT (Agar Scientific) and immediately frozen in liquid nitrogen. 10 mm sections were 16985061 fixed in methanol:acetone (220uC) and blocked with 10 (v/v) normal goat serum (Sigma) in PBS buffer containing 0.1 (w/v) BSA. Primary and secondary antibodies were diluted in PBS buffer containing 0.1 (w/v) BSA and incubated for 1 hour at room temperature. Sections were extensively washed between antibody incubations with PBS. Primary antibodies were detected using appropriate Alexafluor488 or Alexafluor-594 conjugated-secondary antibodies (Molecular Probes). Following antibody labelling, sections were mounted under glass coverslips with Hydromount containing 2.5 (w/v) DABCO (Sigma).ImmunohistochemistryMouse tissues (a minimum of 3 mice per genotype) were immediately fixed in 10 (v/v) Gurr neutral buffered formalin (pH 7.4) for 48 hours before dehydration and embedding in paraffin wax. 5 mm sections were stained with Mayer’sSouthern BlottingDNA from either targeted ES cells or mouse tail tips was digested overnight with appropriate restriction enzymes and thenK7 Knockout MiceFigure 1. Krt7 gene targeting strategy. A. Schematic diagram of the mouse Krt7 gene and upstream sequences, only the proximal part of the gene encompassing exons 1 to 3 is shown. Filled black boxes denote exons 1, 2, 3. The long and short homology arms of the targeting vector are indicated by filled black rectangles. Restriction enzyme sites are as indicated and the open black boxes denote the locations of the DNA probes that were used for southern blotting at the 59 and 39 ends of recombination in targeted ES cells. B. Genotyping of K7 knockout mice, the wildtype allele is 743 bp, the targeted allele is 593 bp. C. RT-PCR analysis of cDNA from the bladder (lanes 1?), lung (lanes 4?), colon (lanes 7?) and kidney (lanes 10?2) amplified with primers to full-length K7 (,1.5 kb) and GAPDH (509 bp). Lanes 1, 4, 7 and 10 are from wildtype mice; lanes 2, 4, 6 and 8 are from heterozygote K7 knockout mice; lanes 3, 6, 9 and 12 are from homozygous K7 knockout mice. M = DNA size standards. D. Northern blot of bladder RNA from wildtype (+/+), heterozygous (+/2) and homozygous (? mice detected with RNA probes to K7 and GAPDH. The position of the 18SK7 Knockou.R cells. Transfected ES cells underwent double-selection with the neomycin analogue G418 (Gibco), at a concentration of 200 mg/ml and with gancyclovir (2 mM). ES clones were screened by Southern blot analysis using DNA probes external to both the 59 and 39 ends of the Krt7 homology arms. Microinjection of ES cell clones and generation of chimeric mice were performed as described previously [14]. Chimeric male mice were mated with C57BL/6 female mice and germline transmission of the targeted Krt7 allele was confirmed by PCR analysis of the resulting offspring. For continued maintenance of the line, K7 knockout mice were backcrossed onto the C57Bl6 background. Genotyping of K7 knockout mice was performed using the following primers: forward primer 59 CTA CTG GCC TCA GGA ATC TAG G 39; reverse primer 1 59 AAG AAC CGT GCG ACT GAG 39 and reverse primer 2 59 GAA TAT CAT GGT GGA AAA TGG C 39 to generate PCR products of 743 bp (wildtype allele) and 593 bp (knockout allele). PCR conditions were as follows: 1 cycle at 94uC for 3 minutes followed by 40 cycles of 94uC (30 sec); 58uC (30 sec); 72uC (1 minute) and a final extension cycle of 72uC for 5 minutes.Immunofluorescence MicroscopyMouse tissues (a minimum of 3 mice per genotype) were embedded in OCT (Agar Scientific) and immediately frozen in liquid nitrogen. 10 mm sections were 16985061 fixed in methanol:acetone (220uC) and blocked with 10 (v/v) normal goat serum (Sigma) in PBS buffer containing 0.1 (w/v) BSA. Primary and secondary antibodies were diluted in PBS buffer containing 0.1 (w/v) BSA and incubated for 1 hour at room temperature. Sections were extensively washed between antibody incubations with PBS. Primary antibodies were detected using appropriate Alexafluor488 or Alexafluor-594 conjugated-secondary antibodies (Molecular Probes). Following antibody labelling, sections were mounted under glass coverslips with Hydromount containing 2.5 (w/v) DABCO (Sigma).ImmunohistochemistryMouse tissues (a minimum of 3 mice per genotype) were immediately fixed in 10 (v/v) Gurr neutral buffered formalin (pH 7.4) for 48 hours before dehydration and embedding in paraffin wax. 5 mm sections were stained with Mayer’sSouthern BlottingDNA from either targeted ES cells or mouse tail tips was digested overnight with appropriate restriction enzymes and thenK7 Knockout MiceFigure 1. Krt7 gene targeting strategy. A. Schematic diagram of the mouse Krt7 gene and upstream sequences, only the proximal part of the gene encompassing exons 1 to 3 is shown. Filled black boxes denote exons 1, 2, 3. The long and short homology arms of the targeting vector are indicated by filled black rectangles. Restriction enzyme sites are as indicated and the open black boxes denote the locations of the DNA probes that were used for southern blotting at the 59 and 39 ends of recombination in targeted ES cells. B. Genotyping of K7 knockout mice, the wildtype allele is 743 bp, the targeted allele is 593 bp. C. RT-PCR analysis of cDNA from the bladder (lanes 1?), lung (lanes 4?), colon (lanes 7?) and kidney (lanes 10?2) amplified with primers to full-length K7 (,1.5 kb) and GAPDH (509 bp). Lanes 1, 4, 7 and 10 are from wildtype mice; lanes 2, 4, 6 and 8 are from heterozygote K7 knockout mice; lanes 3, 6, 9 and 12 are from homozygous K7 knockout mice. M = DNA size standards. D. Northern blot of bladder RNA from wildtype (+/+), heterozygous (+/2) and homozygous (? mice detected with RNA probes to K7 and GAPDH. The position of the 18SK7 Knockou.