title: A neurotoxic phosphoform of Elk-1 associates with inclusions from multiple neurodegenerative diseases.
abstract: Neurodegenerative diseases are characterized by a number of features including the formation of inclusions, early synaptic degeneration and the selective loss of neurons. Molecules serving as links between these shared features have yet to be identified. Identifying candidates within the diseased microenvironment will open up novel avenues for therapeutic intervention. The transcription factor Elk-1 resides within multiple brain areas both in nuclear and extranuclear neuronal compartments. Interestingly, its de novo expression within a single dendrite initiates neuronal death. Given this novel regionalized function, we assessed whether extranuclear Elk-1 and/or phospho-Elk-1 (pElk-1) protein might be associated with a spectrum of human neurodegenerative disease cases including Lewy body Disease (e.g. Parkinson's), Alzheimer's disease, and Huntington's Disease. We first determined the importance of Elk-1 post-translational modifications on its ability to initiate regionalized cell death. We next screened human cases from three major neurodegenerative diseases to look for remarkable levels of Elk-1 and/or pElk-1 protein as well as their association with inclusions characteristic of these diseases. We compared our findings to age-matched control cases. We find that the ability of Elk-1 to initiate regionalized neuronal death depends on a specific phosphosite, T417. Furthermore, we find that T417(+) Elk-1 uniquely associates with several types of inclusions present in cases of human Lewy body Disease, Alzheimer's disease, and Huntington's Disease. These results suggest a molecular link between the presence of inclusions and neuronal loss that is shared across a spectrum of neurodegenerative disease.
authors.affiliation: Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Anup
authors.initials: A
authors.lastname: Sharma
authors.forename: Linda M
authors.initials: LM
authors.lastname: Callahan
authors.forename: Jai-Yoon
authors.initials: JY
authors.lastname: Sul
authors.forename: Tae Kyung
authors.initials: TK
authors.lastname: Kim
authors.forename: Lindy
authors.initials: L
authors.lastname: Barrett
authors.forename: Minsun
authors.initials: M
authors.lastname: Kim
authors.forename: James M
authors.initials: JM
authors.lastname: Powers
authors.forename: Howard
authors.initials: H
authors.lastname: Federoff
authors.forename: James
authors.initials: J
authors.lastname: Eberwine
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism / Q000473:pathology; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D006816:Huntington Disease / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D002479:Inclusion Bodies / Q000378:metabolism* / Q000473:pathology; D020961:Lewy Body Disease / Q000378:metabolism / Q000473:pathology; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D016297:Mutagenesis, Site-Directed; D019636:Neurodegenerative Diseases / Q000378:metabolism* / Q000473:pathology; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D010766:Phosphorylation; D051381:Rats; D013912:Threonine / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D050807:ets-Domain Protein Elk-1 / Q000235:genetics / Q000378:metabolism*
chemical_list: D050807:ets-Domain Protein Elk-1; D013912:Threonine