Basement membrane secretion and remodeling

In addition to using the basement membrane as a substrate for their migration, the follicle cells also extensively remodel this ECM. Through a process that is still poorly understood, the combination of cell movement and new matrix secretion create fibril-like structures in the BM perpendicular to the elongation axis. It has been proposed that this fibrillar matrix then constrains isometric egg chamber growth to promote tissue elongation. The follicle cells are the only fly epithelium that synthesizes all major basement membrane proteins. As such, the egg chamber provides an ideal system to investigate multiple aspects of basement membrane biololgy in the context of a developing organ.
Some of our favorite questions about basement membrane dynamics include
  • How are BM proteins synthesized and secreted exclusively to the basal surface?
  • How do the migrating follicle cells create the unusual fibril-like structures in the BM?
  • How does BM remodeling contribute to elongation morphogenesis?