1. Galectin-3 modulates the polarized surface delivery of β1-integrin in epithelial cells
- Author
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Ellena Hönig, Ralf Jacob, Geri Kreitzer, Tobias von Mach, Karina Ringer, Jenny Dewes, and Natalia Kamm
- Subjects
0301 basic medicine ,animal structures ,Galectin 3 ,Integrin ,Morphogenesis ,Biology ,Endocytosis ,Madin Darby Canine Kidney Cells ,03 medical and health sciences ,Dogs ,Organelle ,Cell polarity ,otorhinolaryngologic diseases ,Animals ,Cell Proliferation ,Epithelial polarity ,Galectin ,Integrin beta1 ,Cell Membrane ,Cell Polarity ,Epithelial Cells ,Cell Biology ,Apical membrane ,Cell biology ,Protein Transport ,stomatognathic diseases ,030104 developmental biology ,biology.protein - Abstract
Epithelial cells require a precise intracellular transport and sorting machinery in order to establish and maintain their polarized architecture. This machinery includes beta-galactoside binding galectins for glycoprotein targeting to the apical membrane. Galectin-3 sorts cargo destined for the apical plasma membrane into vesicular carriers. After delivery of cargo to the apical milieu, galectin-3 recycles back into sorting organelles. We analyzed the role of galectin-3 in the polarized distribution of β1-integrin in MDCK cells. Integrins are located primarily at the basolateral domain of epithelial cells. We demonstrate that a minor pool of β1-integrin interacts with galectin-3 at the apical plasma membrane. Knockdown of galectin-3 decreases apical delivery of β1-integrin. This loss is restored by supplementation with recombinant galectin-3 and galectin-3 overexpression. Our data suggest that galectin-3 targets newly synthesized β1-integrin to the apical membrane and promotes apical delivery of β1-integrin internalized from the basolateral membrane. In parallel, galectin-3 knockout results in a reduction in cell proliferation and an impairment in proper cyst development. Our results suggest that galectin-3 modulates the surface distribution of β1-integrin and affects the morphogenesis of polarized cells.
- Published
- 2018
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