Figure 1
From: Characterization of the Six1 homeobox gene in normal mammary gland morphogenesis
Six1 is dynamically expressed during mouse mammary gland development. (A) Total RNA was isolated from different stages of mammary gland development and analyzed by northern blot. Note that Six1 is expressed at high levels until the fifth day of pregnancy when its level drops off significantly. (B) Mammary glands from Six1 heterozygote females were collected, fixed, and serial sections were stained with hematoxylin and eosin (H&E) or immunostained for EGFP, which replaced one allele of Six1. Arrows point to an island of mammary epithelial cells in the E17.5 embryo, which show intense positive staining for EGFP. Arrowheads point to developing muscles that are also EGFP-positive. Magnification, e17.5: ×40; 5 Weeks Virgin: ×100.