Fig. 8

EdU labeling in juvenile choanocyte chambers shows variation in proliferation rates of individual chambers. Nuclei are stained with DAPI (blue) and EdU (green), and cilia and cytoplasm immunofluorescently labeled with both anti-acetylated alpha tubulin antibody and anti-tyrosinated alpha-tubulin antibody (red). a Juvenile labeled with EdU from 72 to 78 hpr. The right bottom corner of the micrograph is closer to the center of the juvenile, and the top left corner is the outer edge of the juvenile. Many EdU-positive nuclei are found throughout the juvenile body. There are variations in the number of EdU labeling found in chambers ranging from little to no EdU signals (arrows) to many or all nuclei labeled with EdU (arrowheads). b Choanocyte chambers with numerous EdU labeling. These appear to be early choanocyte chambers with relatively short cilia (arrowhead) or little to no cilia (arrow). c A mature choanocyte chamber with no EdU labeling (arrowhead). The small punctate EdU signals (arrow) are presumably proliferating bacteria. Scale bars a 80 μm; b, c 10 μm