Localization of AQP5/AQP8 chimeras in MDCK-II cells: Exchange of the N- and C-termini
Autor: | Ana P. Cotrim, William D. Swaim, Bruce J. Baum, Robert B. Wellner, Sohee Hong |
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Rok vydání: | 2005 |
Předmět: |
Recombinant Fusion Proteins
Blotting Western Biophysics Aquaporin Biology Aquaporins medicine.disease_cause Biochemistry Ion Channels Cell Line Dogs Protein targeting medicine Animals Molecular Biology Epithelial polarity Microscopy Confocal Membrane Proteins Cell Biology Apical membrane Aquaporin 5 Cell biology Blot Cytosol Membrane Cell culture |
Zdroj: | Biochemical and Biophysical Research Communications. 330:172-177 |
ISSN: | 0006-291X |
DOI: | 10.1016/j.bbrc.2005.02.146 |
Popis: | AQP5 and AQP8 possess targeting/retention motifs which mediate their localization to the apical and basolateral membranes, respectively, of polarized MDCK-II cells. As targeting/retention motifs have been localized to the N- or C-termini of other AQPs, we sought the location of such motifs in AQPs 5 and 8 by exchanging their corresponding N- or C-termini and examining the expression, localization, and function of the resultant chimeras. We did not detect the expression of constructs in which the C-terminus of AQP5 was replaced by the C-terminus of AQP8. Substitution of the N-terminus of AQP8 for the N-terminus of AQP5 generated a construct which was trapped intracellularly and did not significantly facilitate transepithelial fluid movement. In contrast, modifications of the N- and C-termini of AQP8 were better tolerated. Substitution of either AQP8 terminus by the corresponding AQP5 terminus generated constructs which localized to basolateral membranes and facilitated transepithelial fluid movement. Our results suggest that, unlike the other AQP targeting/retention signals reported thus far, an AQP8 basolateral targeting/retention motif might reside between the two cytosolic termini. |
Databáze: | OpenAIRE |
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