Abstract
Basement membranes (BMs) are specialized extracellular matrices that are essential for epithelial structure and morphogenesis. However, little is known about how BM proteins are delivered to the basal cell surface or how this process is regulated during development. Here, we identify a mechanism for polarized BM secretion in the Drosophila follicle cells. BM proteins are synthesized in a basal endoplasmic reticulum (ER) compartment from localized mRNAs and are then exported through Tango1-positive ER exit sites to basal Golgi clusters. Next, Crag targets Rab10 to structures in the basal cytoplasm, where it restricts protein delivery to the basal surface. These events occur during egg chamber elongation, a morphogenetic process that depends on follicle cell planar polarity and BM remodeling. Significantly, Tango1 and Rab10 are also planar polarized at the basal epithelial surface. We propose that the spatial control of BM production along two tissue axes promotes exocytic efficiency, BM remodeling, and organ morphogenesis.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 159-168 |
| Number of pages | 10 |
| Journal | Developmental Cell |
| Volume | 24 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jan 28 2013 |
| Externally published | Yes |
Bibliographical note
Funding Information:Trudi Schüpbach, Lisa Fessler, Stefan Baumgartner, and Anne Holz generously provided reagents. We are grateful to Amanda Neisch for help with antibody production, Pam Vanderzalm for advice on coIPs, Guillermina Ramirez-San Juan for MATLAB assistance, and Nick Badovinac for illustrations. We also thank Chip Ferguson, Ben Glick, Lucy O’Brien, and members of the Horne-Badovinac laboratory for comments on the manuscript. This work was supported by National Science Foundation predoctoral fellowships to D.W.L. and A.J.I., as well as a Basil O’Connor Starter Scholar Award (5-FY10-50) from the March of Dimes and NIH grant (R01GM094276) to S.H-B.