Abstract
A 39-kDa protein of unknown function has previously been reported to copurify with the low density lipoprotein receptor-related protein (LRP)/alpha 2-macroglobulin receptor. In this study we demonstrate that a recombinant 39-kDa fusion protein can reversibly bind to the 515-kDa subunit of the LRP/alpha 2-macroglobulin receptor. This interaction inhibits the binding and uptake of the receptor's two known ligands: 1) beta-migrating very low density lipoproteins activated by enrichment with apoprotein E and 2) alpha 2-macroglobulin activated by incubation with plasma proteases or methylamine. A potential in vivo role of the 39-kDa protein is to modulate the uptake of apoE-enriched lipoproteins and activated alpha 2-macroglobulin in hepatic and extrahepatic tissues.
Publication types
-
Research Support, Non-U.S. Gov't
-
Research Support, U.S. Gov't, P.H.S.
MeSH terms
-
Amino Acid Sequence
-
Animals
-
Base Sequence
-
Cell Membrane / chemistry
-
Cholesterol Esters / metabolism
-
Cloning, Molecular
-
DNA / genetics
-
Kidney / chemistry
-
Ligands
-
Lipoproteins, VLDL / metabolism*
-
Low Density Lipoprotein Receptor-Related Protein-1
-
Molecular Sequence Data
-
Oligonucleotides / chemistry
-
Polymerase Chain Reaction
-
Protein Binding
-
Proteins / genetics
-
Proteins / metabolism*
-
Rats
-
Receptors, Immunologic / metabolism*
-
Recombinant Proteins / metabolism
-
Triglycerides / metabolism
-
alpha-Macroglobulins / metabolism*
Substances
-
Cholesterol Esters
-
Ligands
-
Lipoproteins, VLDL
-
Low Density Lipoprotein Receptor-Related Protein-1
-
Oligonucleotides
-
Proteins
-
Receptors, Immunologic
-
Recombinant Proteins
-
Triglycerides
-
alpha-Macroglobulins
-
DNA