P0DOC3 · APOE_CAMDR

Function

function

APOE is an apolipoprotein, a protein associating with lipid particles, that mainly functions in lipoprotein-mediated lipid transport between organs via the plasma and interstitial fluids. APOE is a core component of plasma lipoproteins and is involved in their production, conversion and clearance. Apolipoproteins are amphipathic molecules that interact both with lipids of the lipoprotein particle core and the aqueous environment of the plasma. As such, APOE associates with chylomicrons, chylomicron remnants, very low density lipoproteins (VLDL) and intermediate density lipoproteins (IDL) but shows a preferential binding to high-density lipoproteins (HDL). It also binds a wide range of cellular receptors including the LDL receptor/LDLR and the very low-density lipoprotein receptor/VLDLR that mediate the cellular uptake of the APOE-containing lipoprotein particles. Finally, APOE has also a heparin-binding activity and binds heparan-sulfate proteoglycans on the surface of cells, a property that supports the capture and the receptor-mediated uptake of APOE-containing lipoproteins by cells.

Features

Showing features for binding site.

131720406080100120140160180200220240260280300
TypeIDPosition(s)Description
Binding site161-164heparin (UniProtKB | ChEBI)
Binding site228-235heparin (UniProtKB | ChEBI)

GO annotations

all annotationsall molecular functionvirus receptor activitydna bindingrna bindingcytoskeletal motor activitycatalytic activitygtpase activitystructural molecule activitytransporter activitycytoskeletal protein bindinglipid bindingcyclase activityantioxidant activityoxidoreductase activitytransferase activityhydrolase activitylyase activityisomerase activityligase activityprotein tag activitycargo receptor activityhistone bindingprotein folding chaperonetranslation regulator activitynutrient reservoir activityreceptor ligand activitymolecular transducer activitymolecular adaptor activitytoxin activitycell adhesion mediator activitymolecular function regulator activityvirus coreceptor activitycatalytic activity, acting on a proteincatalytic activity, acting on dnacatalytic activity, acting on rnamolecular carrier activitytranscription regulator activitygeneral transcription initiation factor activitymolecular sensor activitymolecular sequestering activityatp-dependent activityother molecular functionall biological processmitotic cell cyclecytokinesiscytoplasmic translationimmune system processmuscle system processcirculatory system processrenal system processrespiratory system processcarbohydrate metabolic processgeneration of precursor metabolites and energydna replicationdna repairdna recombinationchromatin organizationdna-templated transcriptionregulation of dna-templated transcriptiontrna metabolic processprotein foldingprotein glycosylationamino acid metabolic processmodified amino acid metabolic processlipid metabolic processvitamin metabolic processsulfur compound metabolic processintracellular protein transportnucleocytoplasmic transportautophagyinflammatory responsemitochondrion organizationcytoskeleton organizationmicrotubule-based movementperoxisome organizationlysosome organizationchromosome segregationcell adhesionestablishment or maintenance of cell polarityprogrammed cell deathphotosynthesismrna metabolic processsnrna metabolic processvesicle-mediated transportreproductive processdigestive system processsignalingcell differentiationprotein catabolic processextracellular matrix organizationregulatory ncrna-mediated gene silencingtelomere organizationcell junction organizationwound healingribosome biogenesiscilium organizationanatomical structure developmentcell motilitynervous system processendocrine processprotein maturationtransmembrane transportnucleobase-containing small molecule metabolic processhepaticobiliary system processmembrane organizationprotein-containing complex assemblycell wall organization or biogenesisnitrogen cycle metabolic processprotein localization to plasma membranedefense response to other organismdetoxificationmeiotic nuclear divisionmitotic nuclear divisionmitochondrial gene expressioncarbohydrate derivative metabolic processother biological processall cellular componentnuclear chromosomeextracellular regionextracellular spacecell wallnucleusnuclear envelopenucleoplasmchromosomenucleolusmitochondrionlysosomeendosomevacuoleperoxisomeendoplasmic reticulumgolgi apparatuslipid dropletmicrotubule organizing centercytosolribosomecytoskeletonplasma membraneciliumplastidthylakoidexternal encapsulating structureextracellular matrixcytoplasmic vesicleorganelleother cellular component
Cell color indicative of number of GO terms
AspectTerm
Cellular Componentchylomicron
Cellular Componentextracellular exosome
Cellular Componentextracellular matrix
Cellular Componentextracellular space
Cellular Componenthigh-density lipoprotein particle
Cellular Componentintermediate-density lipoprotein particle
Cellular Componentlow-density lipoprotein particle
Cellular Componentmultivesicular body, internal vesicle
Cellular Componentvery-low-density lipoprotein particle
Molecular Functionamyloid-beta binding
Molecular Functionheparan sulfate proteoglycan binding
Molecular Functionheparin binding
Molecular Functionidentical protein binding
Molecular Functionlipid binding
Molecular Functionlow-density lipoprotein particle receptor binding
Molecular Functionvery-low-density lipoprotein particle receptor binding
Biological Processcholesterol catabolic process
Biological Processcholesterol efflux
Biological Processchylomicron remnant clearance
Biological Processhigh-density lipoprotein particle assembly
Biological Processintermediate-density lipoprotein particle clearance
Biological Processlipoprotein biosynthetic process
Biological Processlipoprotein catabolic process
Biological Processmelanosome organization
Biological Processnegative regulation of amyloid fibril formation
Biological Processnegative regulation of neuron apoptotic process
Biological Processpositive regulation of amyloid-beta clearance
Biological Processtriglyceride-rich lipoprotein particle clearance
Biological Processvery-low-density lipoprotein particle clearance

Keywords

Names & Taxonomy

Protein names

  • Recommended name
    Apolipoprotein E
  • Short names
    Apo-E

Gene names

    • Name
      APOE

Organism names

Accessions

  • Primary accession
    P0DOC3

Subcellular Location

Secreted
Extracellular vesicle
Note: In the plasma, APOE is associated with chylomicrons, chylomicrons remnants, VLDL, LDL and HDL lipoproteins. Lipid poor oligomeric APOE is associated with the extracellular matrix in a calcium- and heparan-sulfate proteoglycans-dependent manner. Lipidation induces the release from the extracellular matrix. Colocalizes with CD63 and PMEL at exosomes and in intraluminal vesicles within multivesicular endosomes.

Keywords

PTM/Processing

Features

Showing features for signal, chain, modified residue, glycosylation.

TypeIDPosition(s)Description
Signal1-18
ChainPRO_000043747119-317Apolipoprotein E
Modified residue142Methionine sulfoxide
Glycosylation211O-linked (GalNAc...) threonine
Glycosylation310O-linked (GalNAc...) threonine

Post-translational modification

APOE exists as multiple glycosylated and sialylated glycoforms within cells and in plasma. The extent of glycosylation and sialylation are tissue and context specific.
Glycated in plasma VLDL.
Phosphorylated by FAM20C in the extracellular medium.

Keywords

PTM databases

Interaction

Subunit

Homotetramer. May interact with ABCA1; functionally associated with ABCA1 in the biogenesis of HDLs. May interact with APP/A4 amyloid-beta peptide; the interaction is extremely stable in vitro but its physiological significance is unclear. May interact with MAPT. May interact with MAP2. In the cerebrospinal fluid, interacts with secreted SORL1. Interacts with PMEL; this allows the loading of PMEL luminal fragment on ILVs to induce fibril nucleation.

Protein-protein interaction databases

Structure

Family & Domains

Features

Showing features for repeat, region.

TypeIDPosition(s)Description
Repeat79-1001
Region79-2548 X 22 AA approximate tandem repeats
Repeat101-1222
Repeat123-1443
Repeat145-1664
Region157-167LDL and other lipoprotein receptors binding
Repeat167-1885
Repeat189-2106
Region209-289Lipid-binding and lipoprotein association
Repeat211-2327
Repeat233-2548
Region265-317Homooligomerization
Region277-289Specificity for association with VLDL

Sequence similarities

Belongs to the apolipoprotein A1/A4/E family.

Keywords

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Sequence processing
    The displayed sequence is further processed into a mature form.
  • Length
    317
  • Mass (Da)
    36,035
  • Last updated
    2016-10-05 v1
  • Checksum
    23EF479EC32DFD3E
MKALWVALVVTLLAGCRAEVEPEPEPEVQLGQEQPEWQGSQPWELALGRLWDYLRWVQTLSDQVQEELLSTQVTQELTALMEETMKEVKAYKAELEEQLSPVAQETRARLSKELQAAQARLGTDMEDLRSRLAHYRNEVQAMLGQTTDELRNRLASHLRKLRKRLLRDAEDLQKRLAVYRAGAVEGAERSVSALRERLGPLVEQGRLGTATTSTLGSQPLRERAEAWGQKLRGRLEAVGARAQDRLDKMREQLEEVRAKVEEQASQMRLQAETFQARLKGWFQPLVEDLQRQWAGLVEKVQQLAVGTTPTPAASKNQ

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
JWIN01034738
EMBL· GenBank· DDBJ
-Genomic DNA No translation available.

Similar Proteins

Disclaimer

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