Steroid hormones may enter cells by diffusion through the plasma membrane. However, we demonstrate here that some steroid hormones are taken up by receptor-mediated endocytosis of steroid-carrier complexes. We show that 25-(OH) vitamin D3 in complex with its plasma carrier, the vitamin D-binding protein, is filtered through the glomerulus and reabsorbed in the proximal tubules by the endocytic receptor megalin. Endocytosis is required to preserve 25-(OH) vitamin D3 and to deliver to the cells the precursor for generation of 1,25-(OH)2 vitamin D3, a regulator of the calcium metabolism. Megalin-/-mice are unable to retrieve the steroid from the glomerular filtrate and develop vitamin D deficiency and bone disease.
| Predicate | Object |
|---|---|
| rdf:type | |
| rdfs:comment |
Steroid hormones may enter cells by diffusion through the plasma membrane. However, we demonstrate here that some steroid hormones are taken up by receptor-mediated endocytosis of steroid-carrier complexes. We show that 25-(OH) vitamin D3 in complex with its plasma carrier, the vitamin D-binding protein, is filtered through the glomerulus and reabsorbed in the proximal tubules by the endocytic receptor megalin. Endocytosis is required to preserve 25-(OH) vitamin D3 and to deliver to the cells the precursor for generation of 1,25-(OH)2 vitamin D3, a regulator of the calcium metabolism. Megalin-/-mice are unable to retrieve the steroid from the glomerular filtrate and develop vitamin D deficiency and bone disease.
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| skos:exactMatch | |
| uniprot:name |
Cell
|
| uniprot:author |
Christensen E.I.,
Dragun D.,
Herz J.,
Jacobsen C.,
Melsen F.,
Nykjaer A.,
Vorum H.,
Walther D.,
Willnow T.E.
|
| uniprot:date |
1999
|
| uniprot:pages |
507-515
|
| uniprot:title |
An endocytic pathway essential for renal uptake and activation of the steroid 25-(OH) vitamin D3.
|
| uniprot:volume |
96
|
| dc-term:identifier |
doi:10.1016/S0092-8674(00)80655-8
|