Journal Article

Apical secretion of Wnt1 in polarized epithelial cells is regulated by exocyst-mediated trafficking

Hideki Yamamoto, Akira Sato and Akira Kikuchi

in The Journal of Biochemistry

Volume 162, issue 5, pages 317-326
Published in print November 2017 | ISSN: 0021-924X
Published online July 2017 | e-ISSN: 1756-2651 | DOI: https://dx.doi.org/10.1093/jb/mvx035
Apical secretion of Wnt1 in polarized epithelial cells is regulated by exocyst-mediated trafficking

More Like This

Show all results sharing these subjects:

  • Cell Biology
  • Biotechnology
  • Biochemistry
  • Molecular and Cell Biology

GO

Show Summary Details

Preview

Abstract

Wnts are glycosylated proteins secreted from various cell types including mesenchymal, hematopoietic and epithelial cells. Directional secretion of Wnts in polarized epithelial cells is unique; Wnt11 is secreted apically, whereas Wnt5a and Wnt3a are secreted basolaterally. Here, we found that Wnt1 is equivalently secreted both apically and basolaterally in MDCK cells. Wnt1 was modified with a complex- or hybrid-type glycan at Asn29 and Asn359 and the high-mannose- or hybrid-type glycan at Asn316. Although glycosylation of Wnt11 at the N-terminal site was shown to be essential for its apical secretion, glycosylation of Asn29 of Wnt1 was not required. Instead, the apical secretion of Wnt1 was inhibited by knockdown of Sec6 and Sec8, suggesting that Wnt1 is secreted apically via exocyst-mediated transport. Basolateral secretion of Wnt1 was mediated by clathrin and AP-1, in mechanism similar to that used by Wnt5a and Wnt3a. Although Wingless was reported to be transcytosed to the basolateral region in the Drosophila wing disc, transcytosis was not involved in the basolateral secretion of Wnt1. Thus, the polarized secretion of Wnt1 is regulated by different mechanisms than other Wnts.

Keywords: epithelial cells; exocyst; glycosylation; secretion; Wnt1

Journal Article.  6343 words.  Illustrated.

Subjects: Cell Biology ; Biotechnology ; Biochemistry ; Molecular and Cell Biology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content. subscribe or login to access all content.