SRSF5 expression in primary ex-vivo erythroid precursors.

A. Flow cytometric analysis of proliferating (black line) and differentiating (grey line) cells. In each graph, the intensity of scatter (FSC) or fluorescence (kit (CD117), CD71, Ter119) is plotted on the Y-axis. The number of events (number of cells) is plotted on the X-axis; it is expressed as 10³-fold (K) in FSC histogram. Proliferating erythroblasts are large cells (high FSC). They express moderate to high levels of Kit and CD71, and low levels of Ter119 on their cell surface. After 2 days of maturation, these cells display a cell size decrease (low FSC), and cell surface phenotype changes, including Kit decrease and higher levels of CD71 and Ter119.B. Immunoblot analysis of SRSF5 expression in fetal liver-derived erythroblasts. Proteins were collected from proliferating cultured erythroblasts (Prolif.) and 2 days after ex-vivo differentiation (Diff.). Western blot analysis was performed using anti-SRSF5 antibody "pAb-SRSF5". Note that SRSF5 virtually vanishes as the cells differentiate.