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Updated: Jun 4, 2026
07:56
Sequential Application of Glass Coverslips to Assess the Compressive Stiffness of the Mouse Lens: Strain and Morphometric Analyses
Published on: May 3, 2016
Intermediate filaments regulate tissue size and stiffness in the murine lens
Douglas S Fudge1, John V McCuaig, Shannon Van Stralen
1Department. of Integrative Biology, University of Guelph, Guelph, Ontario, Canada.
Investigative Ophthalmology & Visual Science
|February 25, 2011
Summary
The beaded filament (BF), a lens-specific intermediate filament (IF), is crucial for maintaining lens structure and function. Its absence impacts lens biomechanics, leading to reduced stiffness and altered shape.
Area of Science:
- Ophthalmology
- Cell Biology
- Biophysics
Background:
- Lens-specific intermediate filaments (IFs) play a role in maintaining ocular structures.
- The beaded filament (BF) is a lens-specific IF whose exact contribution to lens function is not fully understood.
Purpose of the Study:
- To investigate the role of the beaded filament (BF) in lens morphology and biomechanics.
- To define the contributions of CP49, a component of the BF, to lens structure and function.
Main Methods:
- Comparison of wild-type and CP49 knockout (KO) mice.
- Utilized electrophysiological, biomechanical, and morphometric analyses.
- Assessed changes in lens fiber cells and overall lens properties in the absence of CP49.
Main Results:
- Fiber cells lacking CP49 were electrophysiologically similar to wild-type.
- CP49 KO lenses showed decreased stiffness and increased resilience.
- Absence of CP49 resulted in smaller lenses with altered lens:nucleus size ratio and shape (higher axial:equatorial diameter ratio).
Conclusions:
- Beaded filaments (BFs) are essential for maintaining lens structural integrity and clarity with age.
- Tissue-level properties critical for lens function, including biomechanics and morphology, are dependent on lens-specific IFs like CP49.
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