Morphology and gene expression analysis of isolated colonies. (A) Smeared sorted cells or colonies isolated from methylcellulose cultures after 6 days in culture were stained with May-Grünwald Giemsa. cd41:GFP^high and cd41:GFP^medium cells isolated from adult zebrafish WKM (top). Smeared CFU-T colonies isolated from cells cultured in Tpo (middle). CFU-TEs, isolated from cultures grown in the presence of both Epo and Tpo (bottom). Photomicrographs were taken at original magnification ×1000. Scale bar represents 20 µm. (B) CASY profile of sorted cd41:GFP^medium (dark green), cd41:GFP^high (light green), and WKM (red) cells. Peaks represent the average size distribution of cells in µm. (C) qRT-PCR analysis of sorted cd41:GFP cells and colonies grown for 6 days using their appearance in combination with lineage specific genes. The cd41:GFP^medium population was used as the reference standard (fold 1), and bars represent mean values of 3 samples, with error bars representing SD.