Differential Expression and Subcellular Localization of Claudin-7, −8, −12, −13, and −15 Along the Mouse Intestine

Abstract

(HY) S U M M A R Y Among tight-junction proteins, claudins, which play a key role in paracellular transport across epithelia, claudins 1 to 5 are expressed in the intestine, and changes in their abundance and/or distribution are considered to contribute to various gastrointestinal diseases. We investigated, by reverse transcription-PCR, immunoblot, and immunofluorescence analyses, which other claudin species were expressed in the mouse intestine, and whether they showed unique expression profiles. Rabbit polyclonal antibodies against mouse claudin-8, claudin-12, and claudin-15 were generated, and their specificity was verified by immunoblotting using COS-7 cells transfected with individual claudin cDNAs. Claudin-7, -8, -12, -13, and -15 appeared to be expressed in the duodenum, jejunum, ileum, and/or colon with remarkable variations in the expression levels along the intestinal tract, and had distinct subcellular localization in the intestinal epithelium. In addition, claudin-13 and -15 exhibited gradients along the crypt-surface axis of the colon. By contrast,

Expression changes of cell-cell adhesion-related genes in colorectal tumors

“…In mice, claudin-15 was detected among claudins with the highest expression in the colon (41) and it exhibited altered expression in the rat models of colitis and colitis-associated cancer (42). The current study also confirmed the differential expression between AC/AD and NC of two other genes encoding tight junction components: JAM2, a gene that has been found to be hypermethylated in AC (43), and CGN.…”

Dietary tryptophan modulates intestinal immune response, barrier function, antioxidant status and gene expression of TOR and Nrf2 in young grass carp (Ctenopharyngodon idella)

“…Several lines of evidence support a barrier-forming role for ZO-1, occludin, claudin-b, -c and -3 in fish [77,78], whereas claudin-12 and -15 in rats seem to possess pore-forming characteristics [79,80]. Moreover, the up-regulation of ZO-1 and occludin [81] and down-regulation of claudin-15 [82] attenuated the loss of the Fig.…”

Dietary riboflavin deficiency decreases immunity and antioxidant capacity, and changes tight junction proteins and related signaling molecules mRNA expression in the gills of young grass carp (Ctenopharyngodon idella)

“…Therefore, we next investigated the effects of riboflavin on TJ complex and antioxidant system in the gills of fish. acted as barrier-forming TJ proteins in fish [22,23,73], whereas Claudin-12 and Claudin-15 acted as pore-forming TJ proteins in mice [74]. Moreover, studies showed that decreased Claudin-b, -3, Occludin and ZO-1 mRNA levels in fish [23], and up-regulated Claudin-12 and Claudin-15 gene expression in mice [75,76] impaired TJ barrier function.…”