Figure 1

Developmental expression of claudin 7 mRNA in the murine mammary gland. (a) Real-time reverse transcriptase polymerase chain reaction measurement of claudin 7 and keratin 19 from total mammary glands of non-pregnant non-lactating (NPNL) mice, mice at 5, 12, and 18 days of pregnancy (P5, P12, and P18), and mice at 2, 10, 19, 22, and 29 days post partum (L2, L10, L19, L22, and L29). By L29 the pups have weaned themselves, and mammary gland involution is nearly complete. Dotted line, ratio of claudin 7 RNA to keratin 19 at the same time points. Three mice analyzed at each time point. Error bars represent SEM. Where no bar is visible, the SEM falls within the symbol. Asterisks indicate points that differ significantly from values at L2, P < 0.05. (b) In situ hybridization of claudin 7 probes to sections from virgin, pregnant, and lactating mammary glands. Sections labeled A were hybridized to the anti-sense probe; the lower right-hand section labeled S is the sense control. Scale bar, 20 μm.