Abstract:
The average human generates over a trillion mature blood cells each day, through a process
called hematopoiesis. The bone marrow is the primary site of adult hematopoiesis with minor
contributions from the spleen and liver. A functional circulatory system is essential in all
multicellular animals. While most invertebrates have an open circulatory system with
hemolymph and blood cells directly in contact with tissues, vertebrates have a closed
circulatory system where blood flows through blood vessels. Cellular and functional diversity
are greatly increased in more evolved animal classes. However, a common requirement is the
presence of a specialized stem or progenitor cell population that can give rise to the entire blood
system in response to appropriate cues. The function and dynamics of these stem and progenitor
populations are tightly regulated by various cell-intrinsic and -extrinsic signals. Imbalance in
or deregulation of these signals can potentially result in a diverse set of life-threatening
hematological disorders and malignancies. Several molecular regulators of vertebrate
hematopoiesis arose by conservation or gene duplication from invertebrate pathways.
Expectedly, studies on model organisms have given deep insight into development and
regulation of the human blood system. Hence, we aimed to identify and characterize additional
conserved regulators of hematopoiesis as it may provide insights into understanding and
treating blood cell disorders.
