The apoE receptor apoER2 is involved in the maintenance of efficient synaptic plasticity.
ApoER2 is one of the major receptors for ApoE in the brain, and has been shown to be involved not only in lipoprotein endocytosis, as other members of the LDL receptor family of receptors, but also in various cellular functions such as signalling and cellular guidance. By using a model of synaptic plasticity in mice lacking none, one or two alleles of the apoER2 gene, we investigated the implication of such a receptor deficiency on the remodelling process. Our results indicate that animals lacking apoER2 express higher levels of brain APP, as well as both key amyloid peptides, while apoE levels are slightly lower. Following entorhinal cortex lesioning, apoE levels increase in the deafferented hippocampus, while a delay in the increase of APP was observed. Hippocampal amyloid levels are also increased in response to the lesion, and highly potentiated by the complete absence of apoER2 gene. The results suggest a significant role for apoER2 in signalling various proteins in response to massive deafferentation and may participate in maintaining efficient synaptic plasticity and dendritic remodelling.
Petit-Turcotte
Caroline
C
Douglas Hospital Research Center, 6875 LaSalle Blvd, Verdun, Que., Canada H4H 1R3.
Aumont
Nicole
N
Beffert
Uwe
U
Dea
Doris
D
Herz
Joachim
J
Poirier
Judes
J
D016229:Amyloid beta-Peptides / Q000378:metabolism; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism; D000818:Animals; D001057:Apolipoproteins E / Q000378:metabolism; D015153:Blotting, Western / Q000379:methods; D004572:Electrolysis / Q000379:methods; D018728:Entorhinal Cortex / Q000293:injuries / Q000378:metabolism / Q000502:physiology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006624:Hippocampus / Q000166:cytology / Q000293:injuries / Q000502:physiology; D007150:Immunohistochemistry / Q000379:methods; D026502:LDL-Receptor Related Proteins; D051379:Mice; D018345:Mice, Knockout; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism; D018110:Receptors, Lipoprotein / Q000172:deficiency / Q000502:physiology*; D013997:Time Factors
D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; D001057:Apolipoproteins E; D026502:LDL-Receptor Related Proteins; D010446:Peptide Fragments; D018110:Receptors, Lipoprotein; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42); C098773:low density lipoprotein receptor-related protein 8