The role of CXCL12-CXCR4 signaling pathway in pancreatic development.

Chemokine (C-X-C motif) receptor 4 (CXCR4) is the receptor for chemokine (C-X-C motif) ligand 12 (CXCL12, also known as stromal derived factor-1, Sdf1). CXCR4, a protein consisting 352 amino acids, is known to transduce various signals such as cell differentiation, cell survival, cell proliferation, cell chemotaxis and apoptosis [1, 2]. The expression of CXCR4 is observed in embryonic stem cells, blood cells, haematopoietic stem cells, endothelial cells, angioblasts and smooth muscle cells [3-9]. The CXCL12-CXCR4 signaling pathway has very important roles in the embryonic development. Mutant mice for CXCL12 or CXCR4 genes showed lethality due to defects in neurogenesis, angiogenesis, cardiogenesis, myelopoiesis, lymphopoiesis and germ cell development [10-13]. Recently, we reported that CXCL12-CXCR4 signaling pathway has a crucial role in regional specification of the gut endoderm during early development [14]. Here, we would like to focus on the role of CXCL12-CXCR4 signaling pathway in pancreatic development and summarize recent findings of its role in the induction of the pancreatic progenitor cells.