Abstract
The cell surface proteoglycan, syndecan-1, is essential for normal epithelial morphology and function. Syndecan-1 is selectively localized to the basolateral domain of polarized epithelial cells and interacts with cytosolic PDZ (PSD-95, discs large, ZO-1) domain-containing proteins. Here, we show that the polarity of syndecan-1 is determined by its type II PDZ-binding motif. Mutations within the PDZ-binding motif lead to the mislocalization of syndecan-1 to the apical surface. In contrast to previous examples, however, PDZ-binding motif-dependent polarity is not determined by retention at the basolateral surface but rather by polarized sorting prior to syndecan-1's arrival at the plasma membrane. Although none of the four known PDZ-binding partners of syndecan-1 appears to control basolateral localization, our results show that the PDZ-binding motif of syndecan-1 is decoded along the biosynthetic pathway establishing a potential role for PDZ-mediated interactions in polarized sorting.
Original language | English |
---|---|
Pages (from-to) | 1915-1924 |
Number of pages | 10 |
Journal | Traffic |
Volume | 9 |
Issue number | 11 |
DOIs | |
Publication status | Published - 2008 |
Externally published | Yes |
Keywords
- Basolateral
- Epithelia
- PDZ
- Polarity
- Syndecan-1
ASJC Scopus subject areas
- Structural Biology
- Biochemistry
- Molecular Biology
- Genetics
- Cell Biology