Tight junction proteins claudin-2 and -12 are critical for vitamin D-dependent Ca2+ absorption between enterocytes.

ABSTRACT: Ca(2+) is absorbed across intestinal epithelial monolayers via transcellular and paracellular pathways, and an active form of vitamin D(3), 1alpha,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)], is known to promote intestinal Ca(2+) absorption. However, the molecules driving the paracellular Ca(2+) absorption and its vitamin D dependency remain obscure. Because the tight junction proteins claudins are suggested to form paracellular channels for selective ions between neighboring cells, we hypothesized that specific intestinal claudins might facilitate paracellular Ca(2+) transport and that expression of these claudins could be induced by 1alpha,25(OH)(2)D(3). Herein, we show, by using RNA interference and overexpression strategies, that claudin-2 and claudin-12 contribute to Ca(2+) absorp

SUBMITTER: Fujita H 

PROVIDER: S-EPMC2366872 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature