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Neuronal Proteins (neuronal + protein)
Selected AbstractsGreater hippocampal neuronal recruitment in food-storing than in non-food-storing birdsDEVELOPMENTAL NEUROBIOLOGY, Issue 4 2007Jennifer S. Hoshooley Abstract Previous research has shown heightened recruitment of new neurons to the chickadee hippocampus in the fall. The present study was conducted to determine whether heightened fall recruitment is associated with the seasonal onset of food-storing by comparing neurogenesis in chickadees and a non-food-storing species, the house sparrow. Chickadees and house sparrows were captured in the wild in fall and spring and received multiple injections of the cell birth marker bromodeoxyuridine (BrdU). Birds were held in captivity and the level of hippocampal neuron recruitment was assessed after 6 weeks. Chickadees showed significantly more hippocampal neuronal recruitment than house sparrows. We found no seasonal differences in hippocampal neuronal recruitment in either species. In chickadees and in house sparrows, one-third of new cells labeled for BrdU also expressed the mature neuronal protein, NeuN. In a region adjacent to the hippocampus, the hyperpallium apicale, we observed no significant differences in neuronal recruitment between species or between seasons. Hippocampal volume and total neuron number both were greater in spring than in fall in chickadees, but no seasonal differences were observed in house sparrows. Enhanced neuronal recruitment in the hippocampus of food-storing chickadees suggests a degree of neurogenic specialization that may be associated with the spatial memory requirements of food-storing behavior. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007. [source] Requirement of the tumour suppressor APC for the clustering of PSD-95 and AMPA receptors in hippocampal neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2007Atsushi Shimomura Abstract Mutations in the adenomatous polyposis coli (APC) gene are associated with familial adenomatous polyposis and sporadic colorectal tumours. The APC gene is expressed ubiquitously in various tissues, especially throughout the large intestine and central nervous system (CNS). In the CNS, the expression of the APC protein is highest during embryonic and early postnatal development. APC associates through its C-terminal region with postsynaptic density (PSD)-95, a neuronal protein that participates in synapse development. Here, we examined the involvement of APC in synaptogenesis. In cultured hippocampal neurons, both overexpression of a dominant-negative construct that disrupts the APC,PSD-95 interaction and knockdown of APC expression using small interfering RNA (siRNA) inhibited the clustering of PSD-95 and a glutamate receptor subunit, and reduced alpha-amino-3-hydroxy-5-methyl-isoxazole-4-propionate (AMPA)-induced activity of AMPA receptors; however, the clustering of an N -methyl- d -aspartate (NMDA) receptor subunit was unaffected. These results are suggestive of APC involvement in the development of glutamatergic synapses. [source] LRRN6A/LERN1 (leucine-rich repeat neuronal protein 1), a novel gene with enriched expression in limbic system and neocortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2003Laura Carim-Todd Abstract Human chromosome 15q24-q26 is a very complex genomic region containing several blocks of segmental duplications to which susceptibility to anxiety disorders has been mapped (Gratacos et al., 2001, Cell, 106, 367,379; Pujana et al., 2001, Genome Res., 11, 98,111). Through an in silico gene content analysis of the 15q24-q26 region we have identifie1d a novel gene, LRRN6A (leucine-rich repeat neuronal 6A), and confirmed its location to the centromeric end of this complex region. LRRN6A encodes a transmembrane leucine-rich repeat protein, LERN1 (leucine-rich repeat neuronal protein 1), with similarity to proteins involved in axonal guidance and migration, nervous system development and regeneration processes. The identification of homologous genes to LRRN6A on chromosomes 9 and 19 and the orthologous genes in the mouse genome and other organisms suggests that LERN proteins constitute a novel subfamily of LRR (leucine-rich repeat)-containing proteins. The LRRN6A expression pattern is specific to the central nervous system, highly and broadly expressed during early stages of development and gradually restricted to forebrain structures as development proceeds. Expression level in adulthood is lower in general but remains stable and significantly enriched in the limbic system and cerebral cortex. Taken together, the confirmation of LRRN6A's expression profile, its predicted protein structure and its similarity to nervous system-expressed LRR proteins with essential roles in nervous system development and maintenance suggest that LRRN6A is a novel gene of relevance in the molecular and cellular neurobiology of vertebrates. [source] The control of microtubule stability in vitro and in transfected cells by MAP1B and SCG10CYTOSKELETON, Issue 11 2006Percy Bondallaz Abstract In neurons, the regulation of microtubules plays an important role for neurite outgrowth, axonal elongation, and growth cone steering. SCG10 family proteins are the only known neuronal proteins that have a strong destabilizing effect, are highly enriched in growth cones and are thought to play an important role during axonal elongation. MAP1B, a microtubule-stabilizing protein, is found in growth cones as well, therefore it was important to test their effect on microtubules in the presence of both proteins. We used recombinant proteins in microtubule assembly assays and in transfected COS-7 cells to analyze their combined effects in vitro and in living cells, respectively. Individually, both proteins showed their expected activities in microtubule stabilization and destruction respectively. In MAP1B/SCG10 double-transfected cells, MAP1B could not protect microtubules from SCG10-induced disassembly in most cells, in particular not in cells that contained high levels of SCG10. This suggests that SCG10 is more potent to destabilize microtubules than MAP1B to rescue them. In microtubule assembly assays, MAP1B promoted microtubule formation at a ratio of 1 MAP1B per 70 tubulin dimers while a ratio of 1 SCG10 per two tubulin dimers was needed to destroy microtubules. In addition to its known binding to tubulin dimers, SCG10 binds also to purified microtubules in growth cones of dorsal root ganglion neurons in culture. In conclusion, neuronal microtubules are regulated by antagonistic effects of MAP1B and SCG10 and a fine tuning of the balance of these proteins may be critical for the regulation of microtubule dynamics in growth cones. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] Binding partners L1 cell adhesion molecule and the ezrin-radixin-moesin (ERM) proteins are involved in development and the regenerative response to injury of hippocampal and cortical neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2004Matilda A. Haas Abstract Regeneration of the adult central nervous system may require recapitulation of developmental events and therefore involve the re-expression of developmentally significant proteins. We have investigated whether the L1 cell adhesion molecule, and its binding partner, the ezrin-radixin-moesin (ERM) proteins are involved in the neuronal regenerative response to injury. Hippocampal and cortical neurons were cultured in vitro on either an L1 substrate or poly-L-lysine, and ERM and other neuronal proteins were localized immunocytochemically both developmentally and following neurite transection of neurons maintained in long-term culture. Activated ERM was localized to growth cones up to 7 days in vitro but relatively mature cultures (21 days in vitro) were devoid of active ERM proteins. However, ERM proteins were localized to the growth cones of sprouting neuronal processes that formed several hours after neurite transection. In addition, the L1 substrate, relative to poly-L-lysine, resulted in significantly longer regenerative neurites, as well as larger growth cones with more filopodia. Furthermore, neurons derived from the cortex formed significantly longer post-injury neurite sprouts at 6 h post-injury than hippocampal derived neurons grown on both substrates. We have demonstrated that L1 and the ERM proteins are involved in the neuronal response to injury, and that neurons derived from the hippocampus and cortex may have different post-injury regenerative neurite sprouting abilities. [source] Neurochemical biomarkers in the differential diagnosis of movement disorders,MOVEMENT DISORDERS, Issue 10 2009Brit Mollenhauer MD Abstract In recent years, the neurochemical analysis of neuronal proteins in cerebrospinal fluid (CSF) has become increasingly accepted for the diagnosis of neurodegenerative dementia diseases such as Alzheimer's disease and Creutzfeldt,Jakob disease. CSF surrounds the central nervous system, and in the composition of CSF proteins one finds brain-specific proteins that are prioritized from blood-derived proteins. Levels of specific CSF proteins could be very promising biomarkers for central nervous system diseases. We need the development of more easily accessible biomarkers, in the blood. In neurodegenerative diseases with and without dementia, studies on CSF and blood proteins have investigated the usefulness of biomarkers in differential diagnosis. The clinical diagnoses of Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, progressive supranuclear palsy, and corticobasal degeneration still rely mainly on clinical symptoms as defined by international classification criteria. In this article, we review CSF biomarkers in these movement disorders and discuss recent published reports on the neurochemical intra vitam diagnosis of neurodegenerative disorders (including recent CSF ,-synuclein findings). © 2009 Movement Disorder Society [source] Candidate antigens specifically detected by cerebrospinal fluid-IgG in oligoclonal IgG bands-positive multiple sclerosis patientsPROTEOMICS - CLINICAL APPLICATIONS, Issue 7 2007Masashi Nakamura Dr. Abstract The aim of the present study was to detect antigenic proteins that react specifically with cerebrospinal fluid (CSF)-IgG from oligoclonal IgG bands (OB)-positive multiple sclerosis (MS) patients. To identify such antigenic proteins, we developed a rat brain proteome map using 2-DE and applied it to the immunoscreening of brain proteins that react with CSF-IgG but not with serum-IgG in OB-positive MS patients. After sequential MALDI-TOF mass spectrometry, eight proteins [two neuronal proteins (tubulin ,-2 and , enolase-2), HSP-1, Tpi-1 protein and cellular enzymes (creatine kinase, phosphopyruvate hydratase, triosephosphate isomerase and phosphoglycerate kinase-1)] were identified as candidate antigens in seven MS patients. Reactivity to tubulin was seen in Western blotting in four patients, and CSF-specific anti-tubulin IgG was detected in one patient. In addition, CSF-specific anti-gamma enolase IgG was found in another patient. These findings suggest that intrathecal immune responses may occur against a broad range of proteins in MS. [source] Clinical diagnosis and differential diagnosis of CJD and vCJD,APMIS, Issue 1 2002Inga Zerr The most widely distributed form of transmissible spongiform encephalopathy, sporadic Creutzfeldt-Jakob disease, typically affects patients in their sixties. Rapidly progressive dementia is usually followed by focal neurological signs and typically myoclonus. The disease duration in sporadic CJD is shorter than in variant CJD (6 months and 14 months, respectively). The clinical diagnosis in sporadic CJD is supported by the detection of periodic sharp and slow wave complexes in the electroencephalogram, hyperintense signals in basal ganglia on magnetic resonance imaging and elevated levels of neuronal proteins in the cerebrospinal fluid (such as 14-3-3). In contrast to the sporadic form, hyperintense signals in the posterior thalamus ("pulvinar sign") are seen in variant CJD. Following recent developments in diagnostic premortem techniques, clinical criteria for probable sporadic and probable variant CJD were established. Clinicopathological studies on sporadic CJD revealed different phenotypes which are characterized by neuropathological lesion profile, clinical syndrome, codon 129 genotype and type of proteinase K-resistant core of the prion protein. Alzheimer's disease and Lewy body dementia are the most frequent differential diagnoses in sporadic CJD in elderly patients, whereas chronic inflammatory disorders of the central nervous system have to be considered in younger patients. [source] | |||||||||||||||||||||||||