Newly synthesized claudins but not occludin are added to the basal side of the tight junction.

ABSTRACT: A network of claudin strands creates continuous cell-cell contacts to form the intercellular tight junction barrier; a second protein, occludin, is associated along these strands. The physiological barrier remains stable despite protein turnover, which involves removal and replacement of claudins both in the steady state and during junction remodeling. Here we use a pulse-block-pulse labeling protocol with fluorescent ligands to label SNAP/CLIP-tags fused to claudins and occludin to identify their spatial trafficking pathways and kinetics in Madin-Darby canine kidney monolayers. We find that claudins are first delivered to the lateral membrane and, over time, enter the junction strand network from the basal side; this is followed by slow replacement of older claudins in the strands. In con

SUBMITTER: Van Itallie CM 

PROVIDER: S-EPMC6724697 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature