Apelin Receptor Signaling During Mesoderm Development.

The Apelin receptor (Aplnr) is a G-protein coupled receptor which has a wide body distribution and various physiological roles including homeostasis, angiogenesis, cardiovascular and neuroendocrine function. Apelin and Elabela are two peptide components of the Aplnr signaling and are cleaved to give different isoforms which are active in different tissues and organisms.Aplnr signaling is related to several pathologies including obesity, heart disases and cancer in the adult body. However, the developmental role in mammalian embryogenesis is crucial for migration of early cardiac progenitors and cardiac function. Aplnr and peptide components have a role in proliferation, differentiation and movement of endodermal precursors. Although expression of Aplnr signaling is observed in endodermal lineages, the main function is the control of mesoderm cell movement and cardiac development. Mutant of the Aplnr signaling components results in the malformations, defects and lethality mainly due to the deformed heart function. This developmental role share similarity with the cardiovascular functions in the adult body.Determination of Aplnr signaling and underlying mechanisms during mammalian development might enable understanding of regulatory molecular mechanisms which not only control embryonic development process but also control tissue function and disease pathology in the adult body.