Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2021 Jun 15;148(12):dev199281. doi: 10.1242/dev.199281

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© 2021. Published by The Company of Biologists Ltd

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.

PMC Copyright notice

Fig. 2. — Luminal laminin α5 is required for pubertal growth of the mammary epithelium. (A) Schematic showing the outline of tamoxifen induction of K8-CreERT2 during puberty, and qPCR analysis of Lama5 mRNA expression in luminal MECs (+/+ and fl/fl, n=4 samples analyzed) by using wild-type (WT) allele-specific primers compared with primers common for both + and flox alleles (common). (B) Representative images of carmine alum-stained #4 mammary glands of 8-week-old Lama5^+/+;K8-CreERT2 and Lama^fl/fl;K8-CreERT2 treated with tamoxifen. The dashed line shows the outline of ductal growth and the asterisks mark the beginning of epithelium. (C) Representative images of TEBs and ductal ends (marked by black arrowheads and red arrows, respectively) in 6-week-old transgenic mice. (D) Quantification of the number of TEBs in 6-week-old transgenic mice analyzed from #4 mammary glands (K8-CreERT2, n=10; Lama5^+/+;K8-CreERT2, n=6, Lama5^fl/fl;K8-CreERT2, n=9 glands analyzed). (E) Quantification of epithelium length in 8-week-old transgenic mice analyzed from #4 mammary glands (Lama5^fl/fl; n=9, Lama5^fl/fl;K8-CreERT2, n=11 glands analyzed). (F) Quantification of Ki67 positivity in mammary glands of 8-week-old transgenic mice (Lama5^fl/fl; n=4; Lama5^fl/fl;K8-CreERT2, n=8 individuals analyzed). (G) Representative images of #4 mammary glands of 6-week-old Lama5^+/+;K8-CreERT2;R26^mTmG/+ and Lama5^fl/fl;K8-CreERT2;R26^mTmG/+ mice. Images show proximal (closer to the beginning of epithelium) and distal parts of the duct. (H) Quantification of green to red fluorescence ratio in proximal and distal parts of the duct in Lama5^+/+;K8-CreERT2;R26^mTmG/+ and Lama5^fl/fl;K8-CreERT2;R26^mTmG/+ mice (+/+ and fl/fl, both proximal and distal part, n=4 glands quantified). (I) Quantification of epithelial disorganization in ducts of 8-week-old Lama5^+/+;K8-CreERT2 (n=8) and Lama5^fl/fl;K8-CreERT2 (n=8) animals. (J) Representative immunofluorescence images of 8-week-old Lama5^+/+;K8-CreERT2 and Lama5^fl/fl;K8-CreERT2 glands immunostained with K8 and K14 antibodies. Boxes indicate the magnified regions in the right panels. (K) Representative immunofluorescence images of 8-week-old Lama5^+/+;K8-CreERT2 and Lama5^fl/fl;K8-CreERT2 glands immunostained with ZO-1 or MUC1, and K8 antibodies. Data points indicate analysis of individual mice. Data are mean±s.d. *P<0.05, **P<0.01 [unpaired two-tailed Student's t-test (A,E,I) or Welch's ANOVA test (D)]. Scale bars: 5 mm (B); 0.5 mm (C); 200 µm (G); 50 µm (J,K).