Hemangioblasts play a fundamental role in the development of blood vessels and blood cells. These cells are found in the early stages of embryonic development and can give rise to both hematopoietic (blood cell-forming) and endothelial (blood vessel-forming) cell lineages. Hemangioblasts originate from the mesodermal layer of the developing embryo, specifically within the extraembryonic yolk sac and later within the embryo itself. They likely derive from a population of pluripotent stem cells and are among the earliest cells to appear during embryogenesis. Hemangioblasts can give rise to various cell types, making them important during early organogenesis. Hemangioblasts exhibit a remarkable degree of developmental plasticity, with the capacity to differentiate into multiple cell types. Initially, they are bipotent, able to differentiate into either hematopoietic or endothelial cells. However, as development progresses, they become more committed to one lineage or the other. Hemangioblasts contribute to the formation of the hematopoietic system, giving rise to all the major blood cell types such as erythrocytes (red blood cells), leukocytes (white blood cells), and platelets. This ability is vital for the establishment of the circulatory and immune systems. In addition to blood cells, hemangioblasts also can differentiate into endothelial cells, forming the inner lining of blood vessels. This process is critical for the development of the circulatory system, as it ensures the creation of functional blood vessels to transport oxygen and nutrients throughout the body. Notch signalling plays a critical role in these hematopoietic and endothelial cell fate decisions. Activation of Notch signalling promotes endothelial cell development, whilst its inhibition promotes hematopoietic cell development. Notch receptors and ligands are expressed on both hemangioblasts and surrounding cells. Transcription factors such as GATA1, GATA2, and SCL/TAL1 are also critical for the specification of hematopoietic lineage from hemangioblasts. They activate genes necessary for hematopoietic cell development and inhibit endothelial cell differentiation. Conversely, VEGF is a key growth factor involved in endothelial cell development. High levels of VEGF signalling promote endothelial cell differentiation from hemangioblasts. VEGF receptors are expressed on the surface of hemangioblasts, allowing them to respond to VEGF cues. In addition, TGF-β signalling can influence hemangioblast fate by promoting endothelial cell development and inhibiting hematopoietic cell development. The balance of TGF-β signalling can also be modulated by various factors in the microenvironment. Hemangioblasts express specific cell surface markers that can be used for their identification and isolation. These markers include FLK1 (vascular endothelial growth factor receptor 2) and CD34. The expression of these markers can help researchers distinguish hemangioblasts from other cell types in both embryonic and adult tissues. The study of hemangioblasts has significant clinical implications. Understanding their biology may lead to advancements in regenerative medicine, particularly in the treatment of vascular disorders, blood-related diseases, and conditions like ischemic heart disease. Finally, hemangioblasts have been linked to certain diseases, most notably in the context of hemangioblastomas, rare tumours of the central nervous system that are thought to arise from abnormal hemangioblast differentiation. These tumours underscore the importance of understanding hemangioblast biology in the context of pathology. We provide a large product range of research reagents for investigating hemangioblasts, including Tal1 antibodies. Explore our full hemangioblasts product range below and discover more, for less.