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Whole Mount Imaging to Visualize and Quantify Peripheral Lens Structure, Cell Morphology, and Organization
Published on: January 19, 2024
Ubiquitin-proteasome pathway function is required for lens cell proliferation and differentiation
Weimin Guo1, Fu Shang, Qing Liu
1Laboratory for Nutrition and Vision Research, JMUSDA-HNRCA, Department of Ophthalmology, Tufts University, Boston, MA 02111, USA.
Investigative Ophthalmology & Visual Science
|May 26, 2006
Summary
Proteasome activity is essential for lens epithelial cells to proliferate and differentiate into lens fibers. Inhibiting the proteasome blocks key steps in this crucial cellular transformation process.
Area of Science:
- Cell Biology
- Proteolysis
- Developmental Biology
Background:
- The ubiquitin proteasome pathway regulates critical cellular functions, including cell cycle control and protein turnover.
- Understanding lens cell differentiation is vital for eye development and disease research.
Purpose of the Study:
- To investigate the role of the ubiquitin proteasome pathway in regulating lens epithelial cell differentiation into lens fibers.
- To determine if proteasome activity is necessary for the transition from epithelial to fiber cell phenotypes.
Main Methods:
- Rat lens epithelial explants were stimulated with bFGF to induce proliferation and differentiation.
- Bromodeoxyuridine (BrdU) incorporation was used to measure cell proliferation.
- Proteasome activity was inhibited using clasto-lactacystin-beta-lactone.
Main Results:
- bFGF treatment initially increased cell proliferation and multilayering, followed by cell cycle withdrawal.
- Lens epithelial cells exhibited characteristics of lens fibers, including crystallin expression and cell elongation.
- Proteasome inhibition significantly reduced bFGF-induced proliferation and differentiation, impacting crystallin and MIP26 expression.
Conclusions:
- Proteasome activity is indispensable for both the proliferation of lens epithelial cells and their subsequent differentiation into lens fibers.
- The proteasome pathway plays a crucial role in the phenotypic transition required for lens fiber formation.
Related Concept Videos
01:13The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
02:18The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
02:58Regulated Protein Degradation
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
01:17The Proteasome Structure
The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...
The proteasome is an...
00:50Anaphase Promoting Complex
The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
00:50Anaphase Promoting Complex
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