Molecular aspects of avian lung development

Abstract

The pulmonary system develops from a series of complex events that involve coordinated growth and differentiation of distinct cellular compartments. After lung specification of the anterior foregut endoderm, branching morphogenesis occurs generating an intricate arrangement of airways. This process depends on epithelial-mesenchymal interactions tightly controlled by a network of conserved signaling pathways. These signaling events regulate cellular processes and control the temporalspatial expression of multiple molecular players that are essential for lung formation. Additionally, remodeling of the extracellular matrix establishes the appropriate environment for the delivery of diffusible regulatory factors that modulate these cellular processes. In this chapter, the molecular mechanisms underlying avian lung development are thoroughly revised. Fibroblast growth factor, WNT, sonic hedgehog, transforming growth factor-β, bone morphogenetic protein, vascular endothelial growth factor, and regulatory mechanisms such as microRNAs control cell proliferation, differentiation, and patterning of the embryonic chick lung. With this section, we aim to provide a snapshot of the current knowledge of the molecular aspects of avian lung development.