Biomaterial Database

Intracellular apolipoprotein E affects Amyloid Precursor Protein processing and amyloid Abeta production in COS-1 cells. 2001

S Hass, and A Weidemann, and G Utermann, and G Baier

Institute for Medical Biology and Human Genetics, University of Innsbruck, Austria.

The apoE gene has been identified as a major susceptibility locus for late-onset Alzheimer's disease (LOAD). The epsilon4 allele greatly reduces age of onset of LOAD as compared to the wild-type 3 allele. The molecular mechanism(s) underlying the association has not yet been fully elucidated. The apoE protein has been shown to physically interact with the Abeta region of the Amyloid Precursor Protein (APP), but also with the ectodomain of the APP holoprotein itself. In this study we have used apoE fusion proteins containing either the ER retention sequence KDEL or trans-Golgi network (TGN) signal sequence in order to define potential apoE-mediated alterations in APP protein processing. Co-expression and pulse-chase experiments showed that a functional apoE:APP interaction occurs intracellularly which directly affects maturation and subsequently the secretion kinetics of APP. In addition, an epsilon4 allele-specific induction of Abeta production has been demonstrated. apoE3 resulted in increased Abeta production only when targeted to the ER, as observed in cells transfected with an apoE3KDEL fusion protein as well as following treatment with brefeldin A. The findings suggest that in cells that express both apoE and APP, such as astrocytes and microglia, a functional apoE:APP interaction may occur which modulates APP processing and Abeta production.

UI	MeSH Term	Description	Entries
D011499	Protein Processing, Post-Translational	Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.	Amino Acid Modification, Post-Translational,Post-Translational Modification,Post-Translational Protein Modification,Posttranslational Modification,Protein Modification, Post-Translational,Amino Acid Modification, Posttranslational,Post-Translational Amino Acid Modification,Post-Translational Modifications,Post-Translational Protein Processing,Posttranslational Amino Acid Modification,Posttranslational Modifications,Posttranslational Protein Processing,Protein Processing, Post Translational,Protein Processing, Posttranslational,Amino Acid Modification, Post Translational,Modification, Post-Translational,Modification, Post-Translational Protein,Modification, Posttranslational,Modifications, Post-Translational,Modifications, Post-Translational Protein,Modifications, Posttranslational,Post Translational Amino Acid Modification,Post Translational Modification,Post Translational Modifications,Post Translational Protein Modification,Post Translational Protein Processing,Post-Translational Protein Modifications,Processing, Post-Translational Protein,Processing, Posttranslational Protein,Protein Modification, Post Translational,Protein Modifications, Post-Translational
D005786	Gene Expression Regulation	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.	Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000483	Alleles	Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.	Allelomorphs,Allele,Allelomorph
D000544	Alzheimer Disease	A degenerative disease of the BRAIN characterized by the insidious onset of DEMENTIA. Impairment of MEMORY, judgment, attention span, and problem solving skills are followed by severe APRAXIAS and a global loss of cognitive abilities. The condition primarily occurs after age 60, and is marked pathologically by severe cortical atrophy and the triad of SENILE PLAQUES; NEUROFIBRILLARY TANGLES; and NEUROPIL THREADS. (From Adams et al., Principles of Neurology, 6th ed, pp1049-57)	Acute Confusional Senile Dementia,Alzheimer's Diseases,Dementia, Alzheimer Type,Dementia, Senile,Presenile Alzheimer Dementia,Senile Dementia, Alzheimer Type,Alzheimer Dementia,Alzheimer Disease, Early Onset,Alzheimer Disease, Late Onset,Alzheimer Sclerosis,Alzheimer Syndrome,Alzheimer Type Senile Dementia,Alzheimer's Disease,Alzheimer's Disease, Focal Onset,Alzheimer-Type Dementia (ATD),Dementia, Presenile,Dementia, Primary Senile Degenerative,Early Onset Alzheimer Disease,Familial Alzheimer Disease (FAD),Focal Onset Alzheimer's Disease,Late Onset Alzheimer Disease,Primary Senile Degenerative Dementia,Senile Dementia, Acute Confusional,Alzheimer Dementias,Alzheimer Disease, Familial (FAD),Alzheimer Diseases,Alzheimer Type Dementia,Alzheimer Type Dementia (ATD),Alzheimers Diseases,Dementia, Alzheimer,Dementia, Alzheimer-Type (ATD),Familial Alzheimer Diseases (FAD),Presenile Dementia,Sclerosis, Alzheimer,Senile Dementia
D000685	Serum Amyloid A Protein	An ACUTE PHASE REACTION protein present in low concentrations in normal sera, but found at higher concentrations in sera of older persons and in patients with AMYLOIDOSIS. It is the circulating precusor of amyloid A protein, which is found deposited in AA type AMYLOID FIBRILS.	Amyloid Protein SAA,Amyloid Serum Protein SAA,Serum A Related Protein,Amyloid A Precursor,Amyloid A Protein,Amyloid A Protein-Related Serum Component,Amyloid Fibril Protein AA,Amyloid Protein AA,Amyloid Protein AA Precursor,Amyloid-Related Serum Protein (SAA),Serum Amyloid A,Serum Amyloid Protein A,Amyloid A Protein Related Serum Component
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001053	Apolipoproteins	Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.	Apolipoprotein
D001057	Apolipoproteins E	A class of protein components which can be found in several lipoproteins including HIGH-DENSITY LIPOPROTEINS; VERY-LOW-DENSITY LIPOPROTEINS; and CHYLOMICRONS. Synthesized in most organs, Apo E is important in the global transport of lipids and cholesterol throughout the body. Apo E is also a ligand for LDL receptors (RECEPTORS, LDL) that mediates the binding, internalization, and catabolism of lipoprotein particles in cells. There are several allelic isoforms (such as E2, E3, and E4). Deficiency or defects in Apo E are causes of HYPERLIPOPROTEINEMIA TYPE III.	Apo-E,Apo E,Apo E Isoproteins,ApoE,Apolipoprotein E Isoproteins,Apoprotein (E),Apoproteins E,Isoproteins, Apo E,Isoproteins, Apolipoprotein E
D019556	COS Cells	CELL LINES derived from the CV-1 cell line by transformation with a replication origin defective mutant of SV40 VIRUS, which codes for wild type large T antigen (ANTIGENS, POLYOMAVIRUS TRANSFORMING). They are used for transfection and cloning. (The CV-1 cell line was derived from the kidney of an adult male African green monkey (CHLOROCEBUS AETHIOPS).)	COS-1 Cells,COS-7 Cells,COS 1 Cells,COS 7 Cells,COS Cell,COS-1 Cell,COS-7 Cell,Cell, COS,Cell, COS-1,Cell, COS-7,Cells, COS,Cells, COS-1,Cells, COS-7