Creation of <i>MMTV-Flag-Dmp1α</i> mice.

<p>A. The <i>Flag-Dmp1</i> cDNA (<i>Bam</i>HI fragment) was recovered from the pFLEX1-Dmp1 vector and was cloned into the <i>Hind</i>III site of the transgenic vector with <i>MMTV</i> promoter (<i>MMTV-SV40-BSSK</i>). B. Whole mammary gland mounts from 12-week-old nulliparous <i>MDTG</i> (strain 79) and wild-type mice. Scale bars show 2 mm. C. Photomicrographs of nulliparous and multi-parous female mammary glands (MMG) from wild-type and strain 76 <i>MMTV-Flag-Dmp1</i> (<i>MDTG</i>) mice (12-week-old). Wild-type mammary glands were well-dilated with milk production, which became more prominent after getting pregnant. <i>MDTG</i> mammary glands, on the other hand remained small, unopened with little milk production. These mammary glands did not open well with very low milk production even after getting pregnant, making it difficult to feed their pups. The scale bars show 100 µm.