Figure 3

Increased side-branching and proliferation in the mammary glands of young Deaf-1 transgenic mice. A) Wholemounts of thoracic mammary glands harvested from transgenic (a) and wild-type (b) 8 week-old virgin mice. Original magnification, ×7.5. Sections of inguinal mammary glands from transgenic (c and e) and wild-type (d and f) mice stained with haematoxylin and eosin. Original magnification, ×40 (c and d) and ×400 (e and f). B) Immunostaining of mammary sections from transgenic (a) and wild-type (b) 8 week-old mice with anti-BrdU. Original magnification ×400. C) Percent BrdU-positive cells was calculated by counting greater than 1,000 nuclei in 10 random fields for each mouse. At least 5 mice were analyzed for both transgenic and wild-type genotypes. The percentage of BrdU-positive cells in transgenic glands (Tg) was 24.2% ± 7.9% versus 2.5% ± 1.2% in control (wt) glands. Error bars represent standard deviation from the mean. D) Immunostaining of sections from transgenic (a and b) and wild-type (c and d) mammary glands of 8 week-old mice using anti-PRA antibody. Original magnification ×400. E) Percent PRA-positive cells was calculated by counting greater than 1,000 nuclei in 10 random fields for each mouse. At least 4 mice were analyzed for each genotype. The percentage of PRA-positive cells in transgenic glands (Tg) was 32.1% ± 3.0% versus 61.8% ± 2.9% in control (wt) glands. Error bars represent the standard deviation from the mean.