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Updated: May 24, 2026
10:14
An Efficient Sieving Method to Isolate Intact Glomeruli from Adult Rat Kidney
Published on: November 1, 2018
Cubilin is expressed in rat and human glomerular podocytes
Thaneas Prabakaran1, Erik Ilsø Christensen, Rikke Nielsen
1Department of Biomedicine, Section of Cell Biology and Anatomy, University of Aarhus, Aarhus C, Denmark.
Summary
Cubilin, a protein reabsorption receptor, is newly identified in glomeruli and podocytes, alongside megalin. This finding suggests podocytes possess both key endocytic receptors involved in protein reabsorption.
Area of Science:
- Nephrology
- Cell Biology
- Molecular Biology
Background:
- Protein reabsorption in the proximal tubule relies on megalin and cubilin receptors.
- Podocytes can internalize proteins and megalin, but cubilin's presence in glomeruli was unknown.
- Cubilin is vital for albumin reabsorption in proximal tubules.
Purpose of the Study:
- To investigate the presence and expression of cubilin in rat and human glomeruli and podocytes.
- To determine if podocytes express both megalin and cubilin receptors.
Main Methods:
- Immunocytochemistry and RT-PCR on laser-captured glomeruli from rats and humans.
- Cultured podocytes were used to study cubilin expression.
Main Results:
- Cubilin was identified in both rat and human glomeruli, similar to megalin's pattern.
- Cubilin exhibited both surface and intracellular expression in podocytes.
- This confirms cubilin expression in glomerular cells.
Conclusions:
- Podocytes express both key endocytic receptors, cubilin and megalin.
- This finding highlights the role of podocytes in protein handling within the glomerulus.
- Podocytes are now known to possess the primary receptors for protein reabsorption.
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