The function of disulfide bond in tight junction protein, as an oxidative sensor

2016 Fiscal Year Final Research Report

• Project/Area Number: 26460455
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Human pathology
• Research Institution: Hokkaido University (2016); Sapporo Medical University (2014-2015)
• Principal Investigator: TANAKA Satoshi 北海道大学, 医学研究科, 特任准教授 (30374250)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: タイト結合 / ジスルフィド結合 / thioredoxin / redox / ユビキチン

Outline of Final Research Achievements

Occludin, a tight junction transmembrane protein, has 2 cysteine residues in its extracellular loop, which affect its stability and subcellular distribution. Under hypoxia, occludin degradation occurs in the cytoplasm, but occludin in the cytoplasmic membrane is stable. These results suggest that there is disulfide bond formation in or between occludin molecules. Occludin requires ITCH, a ubiquitin E3 ligase, for its degradation via poly-ubiquitination. Occludin interacts with other tight junction proteins, such as tricellulin and claudin-4, but there is no difference in its interactions with tight junction proteins in the presence or absence of cysteine mutations.

Free Research Field

人体病理学、実験病理学、分子病理学