TY - JOUR
T1 - Hair defects and pup loss in mice with targeted deletion of the first cut repeat domain of the Cux/CDP homeoprotein gene
AU - Tufarelli, Cristina
AU - Fujiwara, Yuko
AU - Zappulla, David C.
AU - Neufeld, Ellis J.
PY - 1998/8/1
Y1 - 1998/8/1
N2 - CDP, a ubiquitous homeoprotein homologous to Drosophila cut, is implicated as a transcriptional repressor in several developmental systems. It contains four independent DNA binding domains: three 'cut repeats' plus the homeodomain. The murine Cux/CDP gene spans more than 200 kb and is composed of at least 21 exons. We designed a targeting construct to replace the first cut repeat with a neomycin resistance cassette, introducing a nonsense mutation after position 1319 of the 4.5-kb reading frame of Cux/CDP. We expected to generate a truncated product of ≃60 kDa with this construct, but instead we obtained mice expressing a mutant form of the protein, with an internal deletion of 246 amino acids encompassing cut repeat 1, but intact in the C-terminal region. Ribonuclease protection assays and direct sequencing of mutant cDNA obtained by RT-PCR demonstrate skipping of exons 10 and 11 in the mutant. Homozygous mutant mice, designated Cux/CDPΔCR1, display a phenotype characterized by curly vibrissae and wavy hair. We also observed a high degree of pup loss in litters born to mutant females, most likely on a nutritional basis. The mutant protein is present at levels slightly greater than wild-type, but exhibits the same tissue distribution as wild-type protein, and has approximately normal affinity for known target sequences (though no DNA targets identified to date require the first cut repeat for binding). These results support the hypothesis that the different DNA binding domains of the ubiquitous Cux/CDP protein are responsible for regulation of different genes in diverse tissues during development.
AB - CDP, a ubiquitous homeoprotein homologous to Drosophila cut, is implicated as a transcriptional repressor in several developmental systems. It contains four independent DNA binding domains: three 'cut repeats' plus the homeodomain. The murine Cux/CDP gene spans more than 200 kb and is composed of at least 21 exons. We designed a targeting construct to replace the first cut repeat with a neomycin resistance cassette, introducing a nonsense mutation after position 1319 of the 4.5-kb reading frame of Cux/CDP. We expected to generate a truncated product of ≃60 kDa with this construct, but instead we obtained mice expressing a mutant form of the protein, with an internal deletion of 246 amino acids encompassing cut repeat 1, but intact in the C-terminal region. Ribonuclease protection assays and direct sequencing of mutant cDNA obtained by RT-PCR demonstrate skipping of exons 10 and 11 in the mutant. Homozygous mutant mice, designated Cux/CDPΔCR1, display a phenotype characterized by curly vibrissae and wavy hair. We also observed a high degree of pup loss in litters born to mutant females, most likely on a nutritional basis. The mutant protein is present at levels slightly greater than wild-type, but exhibits the same tissue distribution as wild-type protein, and has approximately normal affinity for known target sequences (though no DNA targets identified to date require the first cut repeat for binding). These results support the hypothesis that the different DNA binding domains of the ubiquitous Cux/CDP protein are responsible for regulation of different genes in diverse tissues during development.
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U2 - 10.1006/dbio.1998.8950
DO - 10.1006/dbio.1998.8950
M3 - Article
C2 - 9698457
AN - SCOPUS:0032146397
SN - 0012-1606
VL - 200
SP - 69
EP - 81
JO - Developmental biology
JF - Developmental biology
IS - 1
ER -