CDB15:0000083 APP — LRP1

Experimentally validated in Human; Orthology-inferred in Mouse, Rat, Frog, Zebrafish, Chicken, Macaque, Pig, Dog, Cow, Chimp, Horse, Marmoset, Sheep

Title

Journal:; Year Published:

Abstract

The role of the low-density lipoprotein receptor-related protein (LRP1) in Alzheimer's A beta generation: development of a cell-based model system.

Journal of molecular neuroscience : MN, 2002; PubMed, Homo sapiens APP — Homo sapiens LRP1

ABSTRACT: The clearance and degradation of extracellular A beta is critical for regulating beta-amyloid deposition, a major hallmark of brains of patients with A beta in Alzheimer's Disease. The low-density lipoprotein receptor-related protein, LRP1, is a large endocytic receptor that significantly contributes to the balance between degradation and production of A beta. An extracellular portion of the LRP, known as the cluster II region can bind to the secreted form of APP (sAPP-KPI). We show here that a GST fusion protein containing the cluster II region of LRP can be used as a 'mini-receptor' that specifically binds to sAPP-KPI from conditioned cultured medium. The binding between the GST-LRP-cluster II fusion protein and sAPP-KPI can be inhibited with the strong binding ligand of LRP1, called receptor-associated protein (RAP). Furthermore, a cell-based in vitro assay system has been developed to monitor the production of total A beta and A beta(1-42) in the presence and absence of RAP in Chinese hamster ovary (CHO) cell lines both deficient in LRP and expressing LRP. A 3-day treatment of the L2 (CHO cells deficient in LRP and overexpressing APP751) and L3 (CHO cells expressing LRP and overexpressing APP751) cell lines with RAP showed a decrease in total A beta and, interestingly, also a decrease in the ratio of A beta42/A beta(total). This cell-based model system and LRP-cluster II mini-receptor will be very useful for screening novel compounds that can reduce A beta accumulation by inhibiting binding of APP-KPI to LRP1.

LDL receptor-related protein, a multifunctional ApoE receptor, binds secreted beta-amyloid precursor protein and mediates its degradation.

Cell, 1995; PubMed, Homo sapiens APP — Homo sapiens LRP1

ABSTRACT: The secreted form of beta-amyloid precursor protein (APP) containing the Kunitz proteinase inhibitor (KPI) domain, also called protease nexin II, is internalized and degraded by cells. We show that the low density lipoprotein (LDL) receptor-related protein (LRP) is responsible for the endocytosis of secreted APP. APPs770 degradation is inhibited by an LRP antagonist called the receptor-associated protein (RAP) and by LRP antibodies and is greatly diminished in fibroblasts genetically deficient in LRP. APPs695, which lacks the KPI domain, is a poor LRP ligand. Since LRP also binds apolipoprotein E (apoE)-enriched lipoproteins and inheritance of the epsilon 4 allele of the apoE gene is a risk factor for Alzheimer's disease (AD), these data link in a single metabolic pathway two molecules strongly implicated in the pathophysiology of AD.

Basic Information on APP

Ligand Name: amyloid beta precursor protein

Other Symbols: AD1, alpha-sAPP

Ligand Location: secreted based on hpa, perplexity, uniprot, cell membrane based on perplexity, uniprot

HGNC Gene Symbol Report: APP

GeneCards: APP

HGNC Gene Group: Receptor ligands

Functional Annotations for APP

Gene Ontologies: PAN-GO, AmiGO 2

Expression Profile: Human Protein Atlas (RNA and protein), Human Cell Atlas (RNA), GEPIA cancer vs normal (RNA), GeneCards (RNA and protein)

Disease Annotations: MalaCards, OMIM, Open Targets Platform, DISEASES (text mining), AI summary (LLM)

Interactions with other Receptors for APP

APP — CD74 ・ APP — FPR2 ・ APP — GPC1 ・ APP — ADRA2A ・ APP — AGER ・ APP — APLP1 ・ APP — APLP2 ・ APP — CNTN3 ・ APP — CNTN4 ・ APP — CNTN5 ・ APP — DCC ・ APP — LRP10 ・ APP — LRP2 ・ APP — LRP4 ・ APP — LRP6 ・ APP — NOTCH1 ・ APP — NOTCH2 ・ APP — RPSA ・ APP — TRPC6

Basic Information on LRP1

Receptor Name: LDL receptor related protein 1

Other Symbols: APR, A2MR, LRP, CD91, LRP1A, APOER, IGFBP3R1, IGFBP-3R

Receptor Location: cell membrane based on hpa, perplexity, uniprot

HGNC Gene Symbol Report: LRP1

GeneCards: LRP1

HGNC Gene Group: MicroRNA host genes, CD molecules, Low density lipoprotein receptors

Functional Annotations for LRP1

Gene Ontologies: PAN-GO, AmiGO 2

Expression Profile: Human Protein Atlas (RNA and protein), Human Cell Atlas (RNA), GEPIA cancer vs normal (RNA), GeneCards (RNA and protein)

Disease Annotations: MalaCards, OMIM, Open Targets Platform, DISEASES (text mining), AI summary (LLM)

Interactions with other Ligands for LRP1

A2M — LRP1 ・ APOE — LRP1 ・ C1QB — LRP1 ・ C3 — LRP1 ・ C4BPA — LRP1 ・ CALR — LRP1 ・ CCN2 — LRP1 ・ F8 — LRP1 ・ F9 — LRP1 ・ FCN2 — LRP1 ・ HSP90B1 — LRP1 ・ LIPC — LRP1 ・ LPL — LRP1 ・ LRPAP1 — LRP1 ・ LTF — LRP1 ・ MDK — LRP1 ・ MMP13 — LRP1 ・ MMP9 — LRP1 ・ PDGFB — LRP1 ・ PLAT — LRP1 ・ PLAU — LRP1 ・ PSAP — LRP1 ・ SERPINA1 — LRP1 ・ SERPINC1 — LRP1 ・ SERPINE1 — LRP1 ・ SERPINE2 — LRP1 ・ SERPING1 — LRP1 ・ TFPI — LRP1 ・ THBS1 — LRP1 ・ ADAMTS1 — LRP1 ・ APOC3 — LRP1 ・ C1QA — LRP1 ・ CCN1 — LRP1 ・ CEMIP — LRP1 ・ HGFAC — LRP1 ・ HMGB1 — LRP1 ・ HMGB2 — LRP1 ・ HPX — LRP1 ・ HSP90AA1 — LRP1 ・ HSPA1A — LRP1 ・ HSPA4 — LRP1 ・ IGFBP7 — LRP1 ・ LIF — LRP1 ・ MBL2 — LRP1 ・ MMP1 — LRP1 ・ PF4 — LRP1 ・ PLAUR — LRP1 ・ SERPIND1 — LRP1 ・ SFTPA1 — LRP1 ・ SFTPD — LRP1 ・ SLIT2 — LRP1 ・ SPARC — LRP1 ・ TIMP1 — LRP1 ・ TIMP3 — LRP1 ・ TNFAIP6 — LRP1 ・ VWF — LRP1