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Unfolded Protein Response (UPR) is activated during normal lens development
Zeynep Firtina1, Melinda K Duncan
1Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.
Gene Expression Patterns : GEP
|November 4, 2010
Summary
The study found that the Unfolded Protein Response (UPR) is activated during mouse lens development. This indicates UPR pathways play a role in the differentiation of lens fiber cells.
Area of Science:
- Ophthalmology
- Cell Biology
- Developmental Biology
Background:
- The eye lens focuses light via epithelial and fiber cells.
- Fiber cell differentiation involves increased membrane protein synthesis.
- Cellular mechanisms managing endoplasmic reticulum stress during this process are unknown.
Purpose of the Study:
- To investigate the role of the Unfolded Protein Response (UPR) in mouse lens fiber cell differentiation.
- To identify specific UPR pathways active during lens development.
Main Methods:
- Examined expression of ER-resident chaperones (BiP, PDI) in embryonic mouse lenses.
- Assessed levels of UPR-associated molecules (XBP1, ATF6, PERK, ATF4).
- Detected active UPR signaling components (spliced XBP1, cleaved ATF6, phospho-eIF2α).
Main Results:
- High expression of BiP and PDI in newly forming fiber cells.
- UPR-associated molecules were expressed during embryogenesis.
- Evidence of active UPR pathways, including spliced XBP1 and cleaved ATF6, in embryonic lenses.
Conclusions:
- UPR activation is evident during normal lens development and fiber cell differentiation.
- These findings suggest a role for UPR in managing cellular stress during lens embryogenesis.
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