Disease relevance of ldlr

• Hepatitis C virus and other flaviviridae viruses enter cells via low density lipoprotein receptor [1].
• Hepatitis C virus (HCV) particles in serum associate with lipoproteins (LPs), and the low-density lipoprotein receptor (LDLr) has been implicated in virus attachment and entry into cells [2].
• Since lactoferrins are known to bind to heparan sulphate proteoglycans and to low density lipoprotein receptor, which in turn act as binding sites for the initial interaction of HSV-1 with host cells, we tested the effect of these proteins on HSV-1 multiplication in Vero cells [3].

High impact information on ldlr

• Immunocytochemical visualization of coated pits and vesicles in human fibroblasts: relation to low density lipoprotein receptor distribution [4].
• This factor(s) is exclusively secreted by astrocytes cocultured with brain capillary endothelial cells, but it also upregulates the LDL receptor on other cell types [5].
• We next investigated the ability of astrocytes to modulate endothelial cell LDL receptor expression [5].
• Upregulation of the low density lipoprotein receptor at the blood-brain barrier: intercommunications between brain capillary endothelial cells and astrocytes [5].
• The numbers of high affinity receptors for LDL was increased more than twofold (range, 2.1-5.6), with concomitant increases in LDL receptor-mediated endocytosis and degradation [6].

Biological context of ldlr

• In the current paper, we report the isolation of a cDNA clone for the LDL receptor from a bovine adrenal cDNA library [7].
• Mixtures of synthetic oligonucleotides encoding the amino acid sequence of two neighboring regions of a single cyanogen bromide fragment were used as hybridization probes to identify a recombinant plasmid containing the LDL receptor cDNA [7].
• Further DNA sequence analysis of pLDLR-1 reveals that the partial cDNA insert encodes 264 amino acids corresponding to the carboxy-terminal 25% of the bovine LDL receptor [8].
• Identification of a point mutation in growth factor repeat C of the low density lipoprotein-receptor gene in a patient with homozygous familial hypercholesterolemia that affects ligand binding and intracellular movement of receptors [9].
• In vitro and in vivo evidence indicates that hemodynamic wall shear stress evokes a diversity of biological responses in vascular endothelial cells, ranging from cell shape changes to alterations in low density lipoprotein receptor expression [10].

Anatomical context of ldlr

• In this study, we have identified mRNA expression in bovine theca and granulosa cells of two lipoprotein receptors, low density lipoprotein receptor (LDLr) and very low density lipoprotein receptor (VLDLr) in granulosa cells from small antral follicles through preovulatory follicles and in theca cells from large and medium sized antral follicles [11].
• Use of antipeptide antibodies to demonstrate external orientation of the NH2-terminus of the low density lipoprotein receptor in the plasma membrane of fibroblasts [12].
• No saturable binding of beta-VLDL that could not be inhibited by antisera to the LDL receptor could be detected in endosomal membranes from livers of either untreated or estradiol-treated rats [13].
• mRNA for low density lipoprotein receptor in brain and spinal cord of immature and mature rabbits [14].
• The distribution of the EDTA-resistant site among early endosomes, late endosomes, and endosome-derived receptor-recycling membranes is similar to that of the LDL receptor and other recycling receptors [13].

Associations of ldlr with chemical compounds

• The major supply of cholesterol, the precursor for steroid and androgen biosynthesis, to ovarian cells is from circulating lipoproteins via membrane receptors from the low density lipoprotein receptor (LDL) superfamily [15].
• In the current studies the sequence of amino acids at the NH2-terminus of the bovine adrenal LDL receptor was determined, and a synthetic peptide corresponding to amino acids 1-16 was prepared [12].
• One of these sites, binding to which is inhibited by 30 mM EDTA, appears identical to the LDL receptor by ligand and immunoblotting and other characteristics [13].
• The increased efficacy was blocked by heparin and was further increased by cell culture in 1% (vs. 10%) fetal bovine serum, suggesting that the effect may, at least in part, be mediated via the LDL receptor [16].
• Cellular internalization of chol-modified oligonucleotide occurred at least partially through the LDL receptor; it was increased in mouse spleen cells by cell culture in lipoprotein-deficient medium and/or lovastatin, and it was decreased by culture in high serum medium [16].

Physical interactions of ldlr

• Thrombospondin signaling through the calreticulin/LDL receptor-related protein co-complex stimulates random and directed cell migration [17].
• Lactoferrin binding to heparan sulfate proteoglycans and the LDL receptor-related protein. Further evidence supporting the importance of direct binding of remnant lipoproteins to HSPG [18].

Other interactions of ldlr

• Expression of mRNA of lipoprotein receptor related protein 8, low density lipoprotein receptor, and very low density lipoprotein receptor in bovine ovarian cells during follicular development and corpus luteum formation and regression [11].
• Characterization of a thrombomodulin cDNA reveals structural similarity to the low density lipoprotein receptor [19].
• Transcytosis of lipoprotein lipase across cultured endothelial cells requires both heparan sulfate proteoglycans and the very low density lipoprotein receptor [20].
• AAK1 overexpression specifically inhibits the AP2-dependent internalization of transferrin receptor and LDL-receptor related protein by functionally sequestering AP2 (Conner and Schmid. J Cell Biol 2003; 162: 773) [21].
• Ovarian follicular steroidogenic acute regulatory protein, low-density lipoprotein receptor, and cytochrome P450 side-chain cleavage messenger ribonucleic acids in cattle undergoing superovulation [22].

Analytical, diagnostic and therapeutic context of ldlr

• Molecular cloning of bovine LDL receptor cDNAs [8].
• Antibodies against this peptide were raised in rabbits and were shown by immunoblotting analysis to react specifically with the bovine LDL receptor [12].
• Vesicle-reconstituted low density lipoprotein receptor. Visualization by cryoelectron microscopy [23].
• In the most highly purified LDL receptor preparation, which had been subjected to the sequential steps of solubilization, DEAE-cellulose chromatography, agarose gel filtration, and phosphatidylcholine/acetone precipitation, the receptor was estimated to constitute about 5% of the total protein [24].
• LDL receptor-dependent binding activity in human liver samples has been semi-quantitated by integrating the areas under the peaks after scanning photographs of ligand blots, and receptor protein determined by radioimmunoassay with purified bovine adrenal LDL receptor protein as the standard [25].

References