Analysis of CDK4 complexes in mouse skin papillomas.
Fresh protein lysates of hyperplastic skin (HS), papillomas at 14 (14w), 20 (20w) and 30 (30w) weeks of promotion were immunoprecipitated (IP) with polyclonal antibodies against mouse CDK4 (A), human CDK4 (B), p27Kip1 (C) and p21Cip1 (D). Immunoblots were developed with polyclonal antibody against cyclin D1, human CDK4 and mouse CDK4. Protein lysates of papillomas of 30 weeks were used in panels C and D. Tg, K5-CDK4 (line 2303) transgenic mice; Wt, wild type mice.