Fig. 4: Myoepithelium specific Kindlin-2 knock-in inhibits the activation of the Notch signaling pathway in mammary glandular ducts.

A Evaluation of Dll1 levels in basal cells (CK5 positive), Notch1 levels in luminal cells (CK8 positive) and the target protein of notch signaling pathway Hes1 levels in 5-month-old mammary gland ducts of K14-Cre + ; Kindlin-2^LSL/LSL compared with K14-Cre-; Kindlin-2^LSL/LSL littermate control mice by IHC with indicated antibodies. In order to better locate myoepithelial cells and luminal epithelial cells, our staining was performed on adjacent slices. Scale bar, 50 µm. B Quantification for the Dll1 levels in basal cells (CK5 positive), Notch1 levels in luminal cells (CK8 positive) and the target protein of Notch signaling pathway Hes1 levels in the ducts of K14-Cre + ; Kindlin-2^LSL/LSL mammary gland compared with K14-Cre-; Kindlin-2^LSL/LSL mammary gland (n = 6). Statistical testing was performed by unpaired t test. Data are presented as mean values ± SD. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. C Quantification for the thickness of mammary gland ducts at the age of 5 months from K14-Cre + ; Kindlin-2^LSL/LSL mammary gland compared with K14-Cre-; Kindlin-2^LSL/LSL mammary gland (n = 6). Statistical testing was performed by unpaired t test. Data are presented as mean values ± SD. *P < 0.05. D Whole-mounted staining of P18.5 mammary gland in K14-Cre + ; Kindlin-2^LSL/LSL or K14-Cre-; Kindlin-2^LSL/LSL littermate control mice. E HE sections staining of P18.5 mammary gland in K14-Cre + ; Kindlin-2^LSL/LSL or K14-Cre-; Kindlin-2^LSL/LSL littermate control mice. Scale bars, 100 µm. F Statistical analysis showing the number of mammary alveolars and cells that make up mammary alveolars in K14-Cre + ; Kindlin-2^LSL/LSL group compared with K14-Cre-; Kindlin-2^LSL/LSL group (n = 10 fields of view at random per genotype). Statistical testing was performed by unpaired t test. Data are presented as mean values ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001.