Figure 2
SRF protein loss is complete by E12.5 in Tie2Cre+/0·Srff/f embryos. Double-label immunofluorescence images of VYS tissue from wild type (A) and SRF-null (B) embryos at E12.5. Tissues were stained for SRF (green), ACTA2 (red), and DNA (blue). Arrows in A highlight SRF-positive nuclei; arrowheads in B mark nuclei lacking SRF. Dashed line indicates division between Ed and Md layers. Magnification = 200×, scale bar = 50 μm; Ed = endoderm, Md = mesoderm. See Additional File 2 for comparable immunofluorescence images from E10.5 and E11.5 tissues. (C) Cytometric analysis of SRF-positive nuclei in E10.5, E11.5, and E12.5 VYS mesoderm cells. Values are expressed as a percentage of total DAPI-stained nuclei counted. SRF protein loss is complete by E12.5. *p = 0.0003; **p = 0.0004; ***p = 0.00008.