Deletion of the p27Kip1 gene restores normal development in cyclin D1-deficient mice

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 98; no. 1; pp. 194 - 199
• Main Authors: Geng, Y, Yu, Q, Sicinska, E, Das, M, Bronson, R T, Sicinski, P
• Format: Journal Article
• Language: English
• Published: United States National Acad Sciences 02.01.2001; National Academy of Sciences; The National Academy of Sciences
• Subjects: Animals; Animals, Newborn; Biological Sciences; Body Weight - genetics; CDC2-CDC28 Kinases; Cell Cycle Proteins; Cells; Crosses, Genetic; Cyclin D1 - deficiency; Cyclin D1 - genetics; Cyclin D1 - metabolism; Cyclin-Dependent Kinase 2; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinase Inhibitor p27; Cyclin-Dependent Kinases - metabolism; Epistasis, Genetic; Female; Gene Deletion; Genetics; Growth - genetics; Histocytochemistry; Male; Mammary Glands, Animal - abnormalities; Mice; Mice, Knockout; Microtubule-Associated Proteins - deficiency; Microtubule-Associated Proteins - genetics; Microtubule-Associated Proteins - metabolism; Mutation; Organ Size - genetics; Phenotype; Phosphorylation; Pituitary Gland - abnormalities; Protein Serine-Threonine Kinases - metabolism; Proteins; Proto-Oncogene Proteins; Retina - abnormalities; Retina - metabolism; Retinoblastoma Protein - metabolism; Suppression, Genetic - genetics; Tumor Suppressor Proteins
• ISSN: 0027-8424; 1091-6490

D-type cyclins (cyclins D1, D2, and D3) are key components of cell cycle machinery in mammalian cells. These proteins are believed to drive cell cycle progression by associating with their kinase partners, cyclin-dependent kinases, and by directing phosphorylation of critical cellular substrates. In addition, D-cyclins play a kinase-independent role by sequestering cell cycle inhibitors p27 Kip1 and p21 Cip1 . In the past, we and others generated cyclin D1-deficient mice and have shown that these mice display developmental abnormalities, hypoplastic retinas, and pregnancy-insensitive mammary glands. To test the significance of cyclin D1–p27 Kip1 interaction within a living mouse, we crossed cyclin D1-deficient mice with mice lacking p27 Kip1 , and we generated double-mutant cyclin D1 −/− p27 −/− animals. Here we report that ablation of p27 Kip1 restores essentially normal development in cyclin D1-deficient mice. Our results provide genetic evidence that p27 Kip1 functions downstream of cyclin D1.