Tricellulin constitutes a novel barrier at tricellular contacts of epithelial cells.
For epithelia to function as barriers, the intercellular space must be sealed. Sealing two adjacent cells at bicellular tight junctions (bTJs) is well described with the discovery of the claudins. Yet, there are still barrier weak points at tricellular contacts, where three cells join together. In this study, we identify tricellulin, the first integral membrane protein that is concentrated at the vertically oriented TJ strands of tricellular contacts. When tricellulin expression was suppressed with RNA interference, the epithelial barrier was compromised, and tricellular contacts and bTJs were disorganized. These findings indicate the critical function of tricellulin for formation of the epithelial barrier.
Ikenouchi
Junichi
J
Department of Cell Biology, Faculty of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
Furuse
Mikio
M
Furuse
Kyoko
K
Sasaki
Hiroyuki
H
Tsukita
Sachiko
S
Tsukita
Shoichiro
S
D000818:Animals; D002478:Cells, Cultured; D004285:Dogs; D004847:Epithelial Cells / Q000201:enzymology / Q000378:metabolism*; D062794:MARVEL Domain Containing 2 Protein; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D008969:Molecular Sequence Data; D062793:Occludin; D034622:RNA Interference; D000071250:Snail Family Transcription Factors; D019108:Tight Junctions / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism
D062794:MARVEL Domain Containing 2 Protein; C508309:Marveld2 protein, mouse; D008565:Membrane Proteins; D062793:Occludin; C568986:Ocln protein, mouse; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors