Abnormalities of the anterior cingulate cortex have previously been described in schizophrenia, major depressive disorder and bipolar disorder. In this study 2-DE was performed followed by mass spectrometric sequencing to identify disease-specific protein changes within the anterior cingulate cortex in these psychiatric disorders. The 2-DE system comprised IPGs 4-7 and 6-9 in the first, IEF dimension and SDS-PAGE in the second dimension. Resultant protein spots were compared between control and disease groups. Statistical analysis indicated that 35 spots were differentially expressed in one or more groups. Proteins comprising 26 of these spots were identified by mass spectroscopy. These represented 19 distinct proteins; aconitate hydratase, malate dehydrogenase, fructose bisphosphate aldolase A, ATP synthase, succinyl CoA ketoacid transferase, carbonic anhydrase, alpha- and beta-tubulin, dihydropyrimidinase-related protein-1 and -2, neuronal protein 25, trypsin precursor, glutamate dehydrogenase, glutamine synthetase, sorcin, vacuolar ATPase, creatine kinase, albumin and guanine nucleotide binding protein beta subunit. All but three of these proteins have previously been associated with the major psychiatric disorders. These findings provide support for the view that cytoskeletal and mitochondrial dysfunction are important components of the neuropathology of the major psychiatric disorders.

There is evidence for both similarity and distinction in the presentation and molecular characterization of schizophrenia and bipolar disorder. In this study, we characterized protein abnormalities in the dorsolateral prefrontal cortex in schizophrenia and bipolar disorder using two-dimensional gel electrophoresis. Tissue samples were obtained from 35 individuals with schizophrenia, 35 with bipolar disorder and 35 controls. Eleven protein spots in schizophrenia and 48 in bipolar disorder were found to be differentially expressed (P < 0.01) in comparison to controls, with 7 additional spots found to be altered in both diseases. Using mass spectrometry, 15 schizophrenia-associated proteins and 51 bipolar disorder-associated proteins were identified. The functional groups most affected included synaptic proteins (7 of the 15) in schizophrenia and metabolic or mitochondrial-associated proteins (25 of the 51) in bipolar disorder. Six of seven synaptic-associated proteins abnormally expressed in bipolar disorder were isoforms of the septin family, while two septin protein spots were also significantly differentially expressed in schizophrenia. This finding represented the largest number of abnormalities from one protein family. All septin protein spots were upregulated in disease in comparison to controls. This study provides further characterization of the synaptic pathology present in schizophrenia and of the metabolic dysfunction observed in bipolar disorder. In addition, our study has provided strong evidence implicating the septin protein family of proteins in psychiatric disorders for the first time.

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Proteomic technologies, such as yeast twohybrid, mass spectrometry (MS), protein/peptide arrays and fluorescence microscopy, yield multi-dimensional data sets, which are often quite large and either not published or published as supplementary information that is not easily searchable. Without a system in place for standardizing and sharing data, it is not fruitful for the biomedical community to contribute these types of data to centralized repositories. Even more difficult is the annotation and display of pertinent information in the context of the corresponding proteins. Wikipedia, an online encyclopedia that anyone can edit, has already proven quite successful1 and can be used as a model for sharing biological data. However, the need for experimental evidence, data standardization and ownership of data creates scientific obstacles. Here, we describe Human Proteinpedia (http://www.humanproteinpedia.org/) as a portal that overcomes many of these obstacles to provide an integrated view of the human proteome. Human Proteinpedia also allows users to contribute and edit proteomic data with two significant differences from Wikipedia: first, the contributor is expected to provide experimental evidence for the data annotated; and second, only the original contributor can edit their data. Human Proteinpedia's annotation system provides investigators with multiple options for contributing data including web forms and annotation servers. Although registration is required to contribute data, anyone can freely access the data in the repository. The web forms simplify submission through the use of pull-down menus for certain data fields and pop-up menus for standardized vocabulary terms. Distributed annotation servers using modified protein DAS (distributed annotation system) protocols developed by us (DAS protocols were originally developed for sharing mRNA and DNA data) permit contributing laboratories to maintain protein annotations locally. All protein annotations are visualized in the context of corresponding proteins in the Human Protein Reference Database (HPRD)3. Figure 1 shows tissue expression data for alpha-2-HS glycoprotein derived from three different types of experiments. Our unique effort differs significantly from existing repositories, such as PeptideAtlas and PRIDE5 in several respects. First, most proteomic repositories are restricted to one or two experimental platforms, whereas Human Proteinpedia can accommodate data from diverse platforms, including yeast two-hybrid screens, MS, peptide/protein arrays, immunohistochemistry, western blots, coimmunoprecipitation and fluorescence microscopy-type experiments. Second, Human Proteinpedia allows contributing laboratories to annotate data pertaining to six features of proteins (posttranslational modifications, tissue expression, cell line expression, subcellular localization, enzyme substrates and protein-protein interactions;). No existing repository currently permits annotation of all these features in proteins. Third, all data submitted to Human Proteinpedia...

Parkinson's disease (PD) is characterized in part by the presence of a-synuclein (a-syn) rich intracellular inclusions (Lewy bodies). Mutations and multiplication of the a-synuclein gene (SNCA) are associated with familial PD. Since Ca 2+ dyshomeostasis may play an important role in the pathogenesis of PD, we used fluorimetry in fura-2 loaded SH-SY5Y cells to monitor Ca 2+ homeostasis in cells stably transfected with either wild-type a-syn, the A53T mutant form, the S129D phosphomimetic mutant or with empty vector (which served as control homeostasis.

Parkin is an ubiquitin-protein ligase (E3), mutations of which cause juvenile onset - autosomal recessive Parkinson's disease, and result in reduced enzymic activity. In contrast, increased levels are protective against mitochondrial dysfunction and neurodegeneration, the mechanism of which is largely unknown. In this study, 2-DE and MS proteomic techniques were utilised to investigate the effects of increased Parkin levels on protein expression in whole cell lysates using in an inducible Parkin expression system in HEK293 cells, and also to isolate potential interactants of Parkin using tandem affinity purification and MS. Nine proteins were significantly differentially expressed (+/-2-fold change; p<0.05) using 2-DE analysis. MS revealed the identity of these proteins to be ACAT2, HNRNPK, HSPD1, PGK1, PRDX6, VCL, VIM, TPI1, and IMPDH2. The first seven of these were reduced in expression. Western blot analysis confirmed the reduction in one of these proteins (HNRNPK), and that its levels were dependent on 26S proteasomal activity. Tandem affinity purification/MS revealed 14 potential interactants of Parkin; CKB, DBT, HSPD1, HSPA9, LRPPRC, NDUFS2, PRDX6, SLC25A5, TPI1, UCHL1, UQCRC1, VCL, YWHAZ, YWHAE. Nine of these are directly involved in mitochondrial energy metabolism and glycolysis; four were also identified in the 2-DE study (HSP60, PRDX6, TPI1, and VCL). This study provides further evidence for a role for Parkin in regulating mitochondrial activity within cells.

Abnormalities in the size and activity of the insular cortex (IC), a brain region involved in auditory hallucinations and language, have been previously found in brain imaging studies in schizophrenia. In addition, cortical layer 2 has been shown to be abnormal in many brain regions in schizophrenia. In this study, 2-D DIGE was used to quantitatively analyse protein expression in schizophrenia and control cases (n = 15/group) in microdissected layer 2 IC tissue. Proteomic analyses revealed 57 significantly differentially expressed (p<0.05) protein spots in schizophrenia. Validation of differential expression of two of the proteins differentially expressed was subsequently confirmed using Western blotting. This work provides evidence of abnormal protein expression in layer 2 of the IC in schizophrenia, supporting previous work of reduced neuronal size in this cortical layer in the IC. Over half of proteins abnormally expressed in this study have not been reported previously in proteomic studies investigating schizophrenia or neurodegenerative disorders. Proteins found to be abnormally expressed appear to collectively impact on neuronal plasticity through roles in neurite outgrowth, cellular morphogenesis and synaptic function.

In vivo imaging techniques have indicated for many years that there is loss of white matter after human traumatic brain injury (TBI) and that the loss is inversely related to cognitive outcome. However, correlated, quantitative evidence for loss of neurons from either the cerebral cortex or the diencephalon is largely lacking. There is some evidence in models of TBI that neuronal loss occurs within the thalamus, but no systematic studies of such loss have been undertaken in the thalamus of humans after blunt head injury. We have undertaken a stereological analysis of changes in numbers of neurons within the dorsomedial, ventral posterior and lateral posterior thalamic nuclei in patients assessed by the Glasgow Outcome Scale as moderately disabled (n = 9), severely disabled (n = 12) and vegetative (n = 10) head-injured patients who survived between 6 h and 3 years, and controls (n = 9). In histological sections at the level of the lateral geniculate body, the cross-sectional area of each nucleus and the number and the mean size of neurons within each nucleus was quantified. A statistically significant loss of cross-sectional area and number of neurons occurred in the dorsomedial nucleus in moderately disabled, and both the dorsomedial and ventral posterior thalamic nuclei in severely disabled and vegetative head-injured patients. However, there was no change in neuronal cell size. In the lateral posterior nucleus, despite a reduction in mean cell size, there was not a significant change in either nuclear area or number of neurons in cases of moderately disabled, severely disabled or vegetative patients. We posit, although detailed neuropsychological outcome for the patients included within this study was not available, that neuronal loss in the dorsomedial thalamus in moderately and severely disabled and vegetative patients may be the structural basis for the clinical assessment in the Glasgow Outcome Scale. In severely disabled and vegetative patients, loss of neurons from the ventral posterior thalamic nucleus may also reflect loss of response to afferent stimuli.