Regulates the proliferation and differentiation of hematopoietic cells. Overexpression block the TPA-induced megakaryocytic differentiation in the K562 cell model. May also prevent cell apoptosis through the activation of the nuclear factor-kappa B (NF-kB) (By similarity). Expressed by bone marrow cells and osteoblasts. Also expressed by ameloblasts in tooth enamel (at protein level). Expressed in enamel organ, ameloblasts, spleen, bone marrow cells and osteoblasts. At 9 dpc expressed in extraembryonic mesodermal layers with its prospective blood islands. Expressed in blood islands at day 12 dpc. Expressed by the intraembryonic primary ectoderm including the primitive streak at day 9 dpc. Expressed in the fetal liver and in circulating cells at 17 dpc, the liver expression disappear around birth (at protein level). Truncated C-terminus.