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Updated: Aug 19, 2025
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An Engineered Split-TET2 Enzyme for Chemical-inducible DNA Hydroxymethylation and Epigenetic Remodeling
Published on: December 18, 2017
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α5 integrin regulates hepatic tight junctions through SRC-TET1-mediated DNA hydroxymethylation
Yuejiao Ma1, Weitao Zhang2, Weihong Li1
1Department of Cell Biology, Capital Medical University, Beijing 100069, China.
Iscience
|December 5, 2022
Summary
Lower alpha5 integrin in liver cirrhosis patients correlates with matrix deposition. Alpha5 integrin signaling impacts tight junction integrity via SRC signaling and epigenetic changes, offering potential therapeutic targets for liver disease.
Area of Science:
- Hepatology
- Cell Biology
- Molecular Biology
Background:
- Hepatic tight junction integrity is crucial for liver function.
- Disruptions in tight junctions are linked to various liver diseases.
- Alpha5 integrin expression is altered in liver cirrhosis.
Purpose of the Study:
- To investigate the role of alpha5 integrin in maintaining hepatic tight junction integrity.
- To elucidate the molecular mechanisms involving alpha5 integrin, SRC signaling, and epigenetic modifications in liver disease.
- To explore potential diagnostic and therapeutic strategies for liver disease.
Main Methods:
- Analysis of alpha5 integrin expression in liver cirrhosis patients.
- Selective silencing of alpha5 integrin in hepatocytes.
- Assessment of tight junction ultrastructure and claudin 1 expression.
- Investigation of SRC signaling pathways.
- Epigenetic analysis including 5-hydroxymethylcytosine and 5-methylcytosine level determination.
- hMeDIP sequencing to analyze gene methylation.
Main Results:
- Lower alpha5 integrin expression in hepatocytes from cirrhotic patients correlates with matrix deposition.
- Alpha5 integrin silencing in hepatocytes disrupts tight junction ultrastructure by downregulating claudin 1.
- This downregulation is dependent on SRC (proto-oncogene, non-receptor tyrosine kinase) signaling.
- Alpha5 integrin signaling influences epigenetic modifications (5-hydroxymethylcytosine and 5-methylcytosine levels).
- Specific hypohydroxymethylation of the claudin 1 gene was observed after alpha5 integrin silencing.
Conclusions:
- Alpha5 integrin plays a significant role in maintaining hepatic tight junction integrity.
- A coordinated mechanism involving alpha5 integrin-SRC signaling and epigenetic modifications regulates hepatic tight junctions.
- Understanding these pathways could lead to novel diagnostics and therapeutics for liver diseases.
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