The Neural Progenitor Cell-Associated Transcription Factor FoxG1 Regulates Cardiac Epicardial Cell Proliferation

Figure 5

The transcription factor FoxG1 is expressed by epicardial cells in vivo and in culture. ((a): a1, a2) In nonrunning (control) mice, selected epicardial cells on the heart surface expressed FoxG1 (arrows). ((b): b1, b2) After 1 week of running exercise, FoxG1 is expressed by the majority of epicardial cells on the heart surface (arrows). Note: this observation agreed with microarray data showing increased levels of FoxG1 mRNA in CD104⁺ cells isolated from running-exercised mice. Bidirectional arrow indicate expression across the entire epicardium. (c1–c3) In culture, murine epicardial cells that highly expressed FoxG1 (see arrows) were positive also for nuclear-localized proliferating cell nuclear antigen (PCNA). Arrowheads label FoxG1-positive cells that are PCNA negative.

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