Dystroglycan down-regulation links EGF receptor signaling and anterior–posterior polarity formation in the Drosophila oocyte
-
Edited by Gertrud M. Schüpbach, Princeton University, Princeton, NJ, and approved July 5, 2006 (received for review May 9, 2006)
Abstract
Anterior–posterior axis formation in the Drosophila oocyte requires activation of the EGF receptor (EGFR) pathway in the posterior follicle cells (PFC), where it also redirects them from the default anterior to the posterior cell fate. The relationship between EGFR activity in the PFC and oocyte polarity is unclear, because no EGFR-induced changes in the PFC have been observed that subsequently affect oocyte polarity. Here, we show that an extracellular matrix receptor, Dystroglycan, is down-regulated in the PFC by EGFR signaling, and this down-regulation is necessary for proper localization of posterior polarity determinants in the oocyte. Failure to down-regulate Dystroglycan disrupts apicobasal polarity in the PFC, which includes mislocalization of the extracellular matrix component Laminin. Our data indicate that Dystroglycan links EGFR-induced repression of the anterior follicle cell fate and anterior–posterior polarity formation in the oocyte.
Footnotes
- *To whom correspondence should be addressed. E-mail: wumin{at}bio.fsu.edu
-
Author contributions: J.S.P. and W.-M.D. designed research, performed research, analyzed data, and wrote the paper.
-
Conflict of interest statement: No conflicts declared.
-
This paper was submitted directly (Track II) to the PNAS office.
- Abbreviations:
- AFC,
- anterior follicle cell;
- AP,
- anterior–posterior;
- CAM,
- clone adjacent mislocalization;
- DG,
- Dystroglycan;
- EGFR,
- EGF receptor;
- MARCM,
- mosaic analysis with a repressible cell marker;
- PFC,
- posterior follicle cell.
- © 2006 by The National Academy of Sciences of the USA
