<i>Osterix</i>-Cre Fate Mapping Marks Bone Marrow Adipocytes.

<p><i>OEC</i> (<b>A–F</b>) and <i>ORt</i> (<b>G–I</b>) activated <i>Ai9</i> Cre reporter expression was observed in bone marrow adipocytes, which appear as empty, round-shaped cells in tissue section. Cre reporter expressing bone marrow adipocytes (<b>A, C, E, G, H</b>) were identified using <i>aP2-EGFPcyan</i> reporter mice (<b>B</b>, blue fluorescent adipocytes noted by white arrows), immunostaining for Perilipin (<b>D</b>, green fluorescent adipocytes noted by white arrows), and hematoxylin counterstained tissue sections revealed round empty holes (<b>I,</b> black arrows). The marking of adipocytes was restricted to the bone marrow compartment as adipose tissue located just outside the bone cortices retained no Cre reporter expression (<b>E, F</b>).