Identification of Scavenger Receptor SR-BI as a High Density Lipoprotein Receptor

  title={Identification of Scavenger Receptor SR-BI as a High Density Lipoprotein Receptor},
  author={Susan L. Acton and Attilio Rigotti and Katherine T. Landschulz and Shangzhe Xu and Helen H. Hobbs and Monty Krieger},
  pages={518 - 520}
High density lipoprotein (HDL) and low density lipoprotein (LDL) are cholesterol transport particles whose plasma concentrations are directly (LDL) and inversely (HDL) correlated with risk for atherosclerosis. LDL catabolism involves cellular uptake and degradation of the entire particle by a well-characterized receptor. HDL, in contrast, selectively delivers its cholesterol, but not protein, to cells by unknown receptors. Here it is shown that the class B scavenger receptor SR-BI is an HDL… 

The role of the high-density lipoprotein receptor SR-BI in cholesterol metabolism

The HDL receptor scavenger receptor class B type I (SR-BI), which mediates selective HDL cholesterol uptake, plays a role in murine HDL metabolism, reverse cholesterol transport and whole-body

Negatively cooperative binding of high-density lipoprotein to the HDL receptor SR-BI.

Application of the "infinite dilution" dissociation rate method established that the binding of (125)I-HDL to SR-BI at 4 °C exhibits negative cooperativity, which should be taken into account when interpreting the results of experiments that explore the mechanism by whichSR-BI mediates ligand binding, lipid transport, and cell signaling.

Influence of the HDL Receptor SR-BI on Lipoprotein Metabolism and Atherosclerosis

The scavenger receptor class B type I (SR-BI) was the first molecularly well-defined cell-surface HDL receptor to be described and the importance of SR-BI in overall HDL cholesterol metabolism and its antiatherogenic activity in vivo has been definitively established by SR- BI gene manipulation in mice.

SR-BI and cholesterol uptake into steroidogenic cells

Increased apolipoprotein M induced by lack of scavenger receptor BI is not activated via HDL-mediated cholesterol uptake in hepatocytes

It is suggested that SR-BI deficiency promoted ApoM expression, but the increased ApiM might be independent from HDL-mediated cholesterol uptake in hepatocytes, as well as up-regulate ApaM expression in serum-containing medium.

Influence of the HDL receptor SR-BI on atherosclerosis.

The scavenger receptor class B, type I (SR-BI) is an HDL receptor that mediates selective cholesterol uptake from HDL to cells that protects against atherosclerosis in mice and may become an attractive target for therapeutic intervention in humans.

Transport of Lipids from High and Low Density Lipoproteins via Scavenger Receptor-BI*

Data indicate that SR-BI is able to exchange cholesterol rapidly between lipoproteins and cell membranes and can mediate the uptake of cholesteryl esters from both classes of lipoprotein, but HDL was a more effective donor.

SR-BI-mediated High Density Lipoprotein (HDL) Endocytosis Leads to HDL Resecretion Facilitating Cholesterol Efflux*

Evidence that HDL retroendocytosis represents one of the pathways for cholesterol efflux is presented, as well as three physiologically relevant cell systems, including the liver cell line HepG2, the adrenal cell line Y1BS1, and phorbol myristate acetate-differentiated THP-1 cells as a model for macrophages.



Characterization in vitro of interaction of human apolipoprotein E-free high density lipoprotein with human hepatocytes.

It is concluded that human hepatocytes possess a specific high affinity site for human HDL with recognition properties similar to those described earlier on rat hepatocytes.

Selective uptake of high‐density lipoprotein–associated cholesteryl esters by human hepatocytes in primary culture

The experiments show that high‐density lipoprotein3 cholesteryl esters selectively taken up by hepatocytes are hydrolyzed independently from the classical lysosomal catabolic pathway, showing a net mass delivery of high‐ density lipop protein cholesterol esters to hepatocytes.

The Class B Scavenger Receptors SR-BI and CD36 Are Receptors for Anionic Phospholipids (*)

Using both direct binding and ligand competition assays in transfected cells, it is found that two class B scavenger receptors, SR-BI and CD36, can tightly bind PS and phosphatidylinositol (PI)-containing liposomes.