Identification of the tau interactome in mouse brain - Alzheimer's ...

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transporter-4 levels and membrane fluidity was achieved. Administration of. E2 brought these changes to near normalcy. Conclusions: It can therefore be.
Poster Presentations P1 transporter-4 levels and membrane fluidity was achieved. Administration of E2 brought these changes to near normalcy. Conclusions: It can therefore be concluded that E2’s beneficial effects seemed to arise from its antilipofuscin, antioxidant and antilipidperoxidative effects, implying an overall anti-aging action. The results of this study will be useful for pharmacological modification of the aging process and applying new strategies for control of age related disorders. P1-010

FUNCTIONAL ANALYSIS OF ALZHEIMER’S DISEASEUPREGULATED GENES

Cathy Mitchelmore1, Niels Jensen2, Christina Dahmcke1, 1Roskilde University, Roskilde; 2University of Southern Denmark, Odense, Denmark. Background: In Alzheimer Disease (AD), hippocampal dysfunction due to neurodegeneration results in the gradual loss of memory and other cognitive abnormalities. Using subtractive cloning with hippocampal tissue from control and AD patients, we previously identified an AD-up regulated gene called NDRG2 and demonstrated that NDRG2 protein localises to senile plaques and degenerating neurons in AD. Methods: We used expression analysis and cell studies to investigate the functions of novel AD-up regulated genes from our subtractive screening. Results: Expression analysis for a further 19 genes from the subtractive screen revealed that 8 of these genes are up regulated more than 3-fold in AD. Here, we present functional data for two of these genes: the DNA replication factor CIZ1 (CDKN1A interacting zinc finger protein 1) and a GDP-exchange factor called RGL1 (Ral-GDP dissociation stimulator-Like1). Overexpression of RGL1 in Neuro2A cells causes them to extend highly branched neurites. For CIZ1, we show that alternative splicing in exon 8 results in a short isoform of CIZ1 which is up regulated in AD brains relative to the fulllength CIZ1 protein. Using cell transfect ions, we show that this isoform lacks a glutamine-rich region which is required for CIZ1 to associate with the nuclear matrix and to form nuclear foci. Conclusions: Deregulation of cell cycle control in AD, via effects on the Ras or CDKN1A pathways, may lead to cell death in terminally differentiated neurons. Our identification and functional analysis of genes which are up regulated in the CA1 region of AD patients with slight to moderate degrees of dementia highlights some of the molecular changes that occur early during the neurodegenerative process.

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IDENTIFICATION OF THE TAU INTERACTOME IN MOUSE BRAIN

Dieder Moechars1, Marc Mercken1, Fred Van Leuven2, Gerard Joberty3, Ilse Dewachter4, Adele Rowley5, Joris Winderickx6, Eric Karran1, 1Janssen, Beerse, Belgium; 2Experimental Genetics group - LEGTEGG - KULeuven, Leuven; 3Cellzome AG, Heidelberg; 4Universite Catholique de Louvain, Woluwe St-Lambert; 5Cellzome Limited, Cambridge; 6K.U. Leuven, Heverlee. Background: Microtubule-associated protein tau (MAPT) assembles into neurofibrillary tangles (NFT) in a variety of neurodegenerative tauopathies, a group of disorders that includes Alzheimer’s disease and frontotemporal dementias. The tau mediated neurodegeneration that is observed in these tauopathies may result from toxic gain-of-function, derived from the (pre-) aggregates and/or loss-of-function of tau. However the potential physiological functions of protein tau, besides promoting the stabilization of microtubules, and the pathogenic pathways that result in protein tau mediated disease are today not well understood. To increase our knowledge on the biology of protein tau we initiated the identification of (sets of) proteins that interact with protein tau and form physiologically relevant, functional interdependent protein-complexes. Methods: Tau complexes were isolated from normal mouse brains using a panel of antitau antibodies. tau candidate interactors were identified following precise Mass Spectrometry quantification using iTRAQ (isobaric tag for relative and absolute quantification) labeling, comparing protein levels from anti-

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tau and control antibody precipitates. Results: Analysis of the tau protein complexes derived from mouse brain resulted in the identification of many specific tau interacting proteins. Among those, a significant number have previously been reported to interact with tau and thus confirm the validity of the methodology used. Examples are Tubulin subtypes (TUBA1, TUBA4, TUBB2C, TUBB2B, TUBB5), Dynactin complex (DCTN2, DCTN3, DCTN4, ACTR1A, ACTR1b, DCTN1, CAPZB, CAPZA2), PP2A complex (PPP2R1A, PPP2CB, PPP2R2A), PP2B complex (PPP3CA, PPP3R1), 14-3-3 proteins (Ywhaq, Ywhaz, Ywhae, Ywhag, Ywhah, Ywhab), aminopeptidase NPEPPS and Triose-phosphate isomerase (TPI). Besides these a series of unknown potential tau interacting proteins were identified. Some of these can be catalogued as microtubule associated proteins, molecular chaperones, ubiquitin proteases, oxidative stress related proteins and synaptic function related proteins. Further validation of the interaction and the potential role of the interacting proteins in tau biology, is currently under evaluation using biochemical and phenotypic readouts in a variety of cellular and animal models. Conclusions: The combination of high quality anti-tau antibodies with state-of-the-art quantitative mass spectrometry let to the identification of many potential new tau interactors. Validation and functional relevance of newly identified interactors will be presented.

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THE EFFECT OF SUB-ANESTHETIC DOSE OF KETAMINE ON ACQUISITION, CONSOLIDATION AND RETRIEVAL STAGES OF WATER MAZE REFERENCE MEMORY

Maryam Moosavi, Golnaz Yadollahi Khales, Asadollah Zarifkar, Karim Rastegar, Shiraz University of Medical Sciences, Shiraz. Background: Oxidative stress and protein damage are the events related to the pathogenesis of Alzheimer’s disease. The hippocampus which is mainly affected in Alzheimer’s disease is a critical structure in declarative memory of humans and spatial memory of rodents. Previous studies have shown that a single sub-anesthetic dose of ketamine increases lipid peroxidation and protein damage in the hippocampus. It is documented that hippocampus is involved in three stages of memory: acquisition, consolidation and retrieval. Considering the ketamine-induced protein damage in the hippocampus and also its antagonism effect of NMDA receptors, this study was aimed to assess the effect of sub-anesthetic dose of ketamine on those three stages. Methods: Adult male Sprague-Dawely rats weighing 250-350 were trained in a single session consisting of 8 trials. The probe test was done 24 hours later to assess memory retention. To assess the effect of ketamine on acquisition, ketamine (25mg/kg/ip) was administered 30 minutes before training; to assess its effect on consolidation phase, it was injected immediately after training and to assess its effect on retrieval, ketamine (25mg/kg/ip) was injected 30 minutes before probe trial. Results: The results showed that pretraining administration of sub-anesthetic dose of ketamine deteriorates learning. Post-training administration of ketamine did not affect animal’s performance in probe trial, and pre-probe administration of ketamine impaired animal’s performance in probe trial. Conclusions: This work shows that sub-anesthetic ketamine can impair memory acquisition and retrieval, but does not affect memory consolidation.

P1-013

CELLULAR MODELS OF SEEDED AGGREGATION OF ALPHA-SYNUCLEIN AND TAU

Takashi Nonaka1, Takeshi Iwatsubo2, Sayuri Watanabe3, Masato Hasegawa4, Masami Suzukake-Masuda5, 1Tokyo Metropolitan Institute of Medical Science, Tokyo; 2The University of Tokyo, Tokyo; 3The University of Tokyo, Tokyo; 4Tokyo Metropolitan Institute of Medical Science, Tokyo; 5Tokyo Metropolitan Institute of Medical Science, Tokyo.