Related Experiment Video
Updated: Oct 3, 2025
07:03
Imaging Denatured Collagen Strands In vivo and Ex vivo via Photo-triggered Hybridization of Caged Collagen Mimetic Peptides
Published on: January 31, 2014
12.1K
Visualized procollagen Iα1 demonstrates the intracellular processing of propeptides
Toshiaki Tanaka1, Koji Moriya2, Makoto Tsunenaga3
1School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Japan ttanaka@bio.titech.ac.jp.
Life Science Alliance
|February 19, 2022
Summary
This study visualizes type I procollagen processing, revealing intracellular cleavage and transport mechanisms. Dysfunctional collagen processing in hepatic stellate cells is linked to hepatic fibrosis.
Area of Science:
- Cell Biology
- Biochemistry
- Pathology
Background:
- Type I procollagen processing is crucial for collagen fibril formation, but the exact steps are debated.
- Understanding this process is vital for insights into connective tissue disorders and fibrotic diseases.
Purpose of the Study:
- To elucidate the intracellular processing and secretion pathway of type I procollagen.
- To investigate the role of procollagen processing defects in activated hepatic stellate cells and their link to hepatic fibrosis.
Main Methods:
- Development of a live cell imaging system using fluorescently tagged type I pre-procollagen α1.
- Live imaging and immunostaining techniques to track procollagen processing and localization.
- High-throughput assaying of fluorescence in culture medium to quantify collagen secretion.
Main Results:
- Demonstrated intracellular cleavage of C-propeptide in the perinuclear region (including ER) and N-propeptide transport to the extracellular space.
- Identified the rate-limiting step for collagen secretion occurs post-procollagen synthesis.
- Revealed aberrant procollagen processing in activated hepatic stellate cells, leading to abnormal collagen fibrils.
Conclusions:
- The study clarifies the intracellular processing and secretion pathway of type I procollagen.
- Defects in procollagen processing are implicated in the pathogenesis of hepatic fibrosis through aberrant collagen secretion by hepatic stellate cells.
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