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[Identification of proposed laboratories for leptospirosis surveillance at the regional and multiregional levels].

A geographic emplacement of reference Centres for the epidemiological control is proposed here according to recommendation by the Istituto Superiore di Sanità and the instructions of the WHO. While the ordinary laboratories make serodiagnosis for clinical use only, the reference Centres must carry out the epidemiological control by typing of leptospires strains in order to establish the prevalence of the serotypes in the different territories. For these more complex epidemiological techniques, closer relations between the Centres and the Istituto Superiore di Sanità are necessary. The national map proposed, object of discussion at the meeting, refers to reference Centres (location and person) that have made themselves available for this duty.

Humans↗

Mapping a conserved conformational epitope from the M protein of group A streptococci.

The carboxyl terminus of the M protein of group A streptococci (GAS) is highly conserved and contains epitopes that have been shown to induce opsonic antibodies and protection against GAS infection. This region of the protein can also stimulate T cells, which can react in vitro with heart antigens. Since different segments of the carboxyl terminus may be involved in immunity to GAS and in the pathogenesis of autoimmune disease (rheumatic heart disease), it is important to precisely define critical epitopes. However, the M protein is known to be a coiled coil, and a critical immunodominant antibody-binding epitope within this region (peptide 145, a 20-mer with the sequence LRRDLDASREAKK-QVEKALE) is shown here to be conformational. Thus, small synthetic overlapping peptides of 8-12 amino acids in length that span peptide 145 (p145) were unable to capture antibodies present in p145-immune mouse sera or in endemic human sera, even though antibodies raised to these small peptides coupled to diphtheria toxoid could bind the smaller peptides and, in some cases, p145. A series of mutated peptides in which every residue of p145 was sequentially altered also failed to identify critical residues for antibody binding. We thus devised a strategy to produce chimeric peptides in which small peptides copying the M protein sequence were displayed within a larger 28-mer peptide derived from the sequence of the GCN4 leucine zipper DNA binding protein of yeast. A 12-amino-acid window of the p145 sequence was inserted into the GCN4 peptide in such a way as to preserve any potential helical structure. The window was moved along one residue at a time to give a series of peptides representing p145. Circular dichroism demonstrated that these larger chimeric peptides and p145, but not a shorter 12-mer peptide, displayed alpha-helical potential in 50% trifluoroethanol. Certain chimeric peptides efficiently captured antibodies specific for p145 and thus enabled us to map the minimal antibody-binding sequence. RRDLDASREAKK, referred to as J(1)2. The chimeric peptide containing this sequence, referred to as J2, was able to inhibit opsonization of GAS by human antisera containing anti-peptide 145 antibodies. The T-cell response from p145-immunized responder B10.BR mice to J2 and J(I)2 was much lower than the response to p145 and mapped to a different peptide.

Animals↗

Chronomes, time structures, for chronobioengineering for "a full life".

Week-long or longer monitoring of blood pressure and heart rate, coupled to time-structure analyses, can help detect disease-risk elevations, as a warning of the need for a preventive prehabilitation. Within the normal range of physiologic variation, computer methods quantify time structures, or chronomes, that can serve as reference values. The major applied purpose for mapping chronomes is the detection of disease-risk syndromes such as blood pressure "overswinging" and heart rate "underswinging." Too much blood pressure variability (circadian hyperamplitude tension; CHAT), is a risk factor for vascular disease. Other risk syndromes are chronome alterations of heart rate variability (CAHRVs), consisting of a loss of "jitter", i.e., a reduced standard deviation of heart rate or of alterations in the spectral element of the heart-rate-variability chronome, such as in the correlation dimension, an endpoint of deterministic chaos. These alterations can again serve for prehabilitation. On the basic side, the spectral element of the heart-rate-variability chronomes extends from focus on the heartbeat's period of about 1 second to periods in heart rate and its standard deviation that are numerical equivalents of about 10.5- and about 21-year cycles of solar activity. A seemingly unnatural physiologic rhythm or pattern (such as one of 81.6 hours) may correspond numerically to a purely physical environmental rhythm. For example, interplanetary magnetic storms, with their cycles as external chronome components, trigger myocardial infarctions, strokes, and traffic accidents. The systematic monitoring of external rhythms along with physiologic ones for the concurrent analysis of rhythms with longer and longer periods could detect alterations anywhere in and between the 1 cycle/sec and the 1 cycle/10.5- or 21-years regions of the spectrum. Chronobiomimetic engineering for discovering both instantaneous and long-term chronorisk alterations can provide warnings of increased risk. If risk-lowering therapy is then instituted automatically, instrumented health care will be extended beyond the pacemaker-cardioverter-defibrillator, which focuses on the frequency of 1 cycle/sec. Instrumentation that automatically detects blood pressure that varies too much and heart rate that varies too little is needed for prompting prophylactic CHAT and CAHRV treatment. A database of reference values that can be used for chronodiagnosis is now accumulating.

Accidents, Traffic↗

CAFTAN: a tool for fast mapping, and quality assessment of cDNAs.

BACKGROUND: The German cDNA Consortium has been cloning full length cDNAs and continued with their exploitation in protein localization experiments and cellular assays. However, the efficient use of large cDNA resources requires the development of strategies that are capable of a speedy selection of truly useful cDNAs from biological and experimental noise. To this end we have developed a new high-throughput analysis tool, CAFTAN, which simplifies these efforts and thus fills the gap between large-scale cDNA collections and their systematic annotation and application in functional genomics. RESULTS: CAFTAN is built around the mapping of cDNAs to the genome assembly, and the subsequent analysis of their genomic context. It uses sequence features like the presence and type of PolyA signals, inner and flanking repeats, the GC-content, splice site types, etc. All these features are evaluated in individual tests and classify cDNAs according to their sequence quality and likelihood to have been generated from fully processed mRNAs. Additionally, CAFTAN compares the coordinates of mapped cDNAs with the genomic coordinates of reference sets from public available resources (e.g., VEGA, ENSEMBL). This provides detailed information about overlapping exons and the structural classification of cDNAs with respect to the reference set of splice variants. The evaluation of CAFTAN showed that is able to correctly classify more than 85% of 5950 selected "known protein-coding" VEGA cDNAs as high quality multi- or single-exon. It identified as good 80.6 % of the single exon cDNAs and 85 % of the multiple exon cDNAs. The program is written in Perl and in a modular way, allowing the adoption of this strategy to other tasks like EST-annotation, or to extend it by adding new classification rules and new organism databases as they become available. We think that it is a very useful program for the annotation and research of unfinished genomes. CONCLUSION: CAFTAN is a high-throughput sequence analysis tool, which performs a fast and reliable quality prediction of cDNAs. Several thousands of cDNAs can be analyzed in a short time, giving the curator/scientist a first quick overview about the quality and the already existing annotation of a set of cDNAs. It supports the rejection of low quality cDNAs and helps in the selection of likely novel splice variants, and/or completely novel transcripts for new experiments.

Chromosome Mapping↗

Fine mapping and characterization of the Rous sarcoma virus Pr76gag late assembly domain.

The p2 region of the Rous sarcoma virus (RSV) Gag polyprotein contains an assembly domain, which is required late in replication for efficient budding of virus-like particles from cells (J. W. Wills, C. E. Cameron, C. B. Wilson, Y. Xiang, R. P. Bennett, and J. Leis, J. Virol. 68:6605-6618, 1994). This domain, referred to as the L domain, was previously mapped to the 11 amino acids of p2b. Through the analysis of a series of deletion and substitution mutations, the L domain has now been fine mapped to a highly conserved amino acid sequence, PPPPYV of p2b. Sequences flanking PPPPYV motif can be deleted without any effect on budding. Defects caused by L-domain deletions can be rescued by placing a wild-type copy of the sequence at several other positions in RSV Gag. A proline-rich P(S/T)APP motif is found in many retroviral Gag polyproteins; the motif found in the p6 region of human immunodeficiency virus type 1 has been implicated in late functions of the virus. Substitution of the RSV L domain with this motif in a 10-amino-acid sequence derived from visna leukemia virus results in wild-type release of virus particles from cells. In contrast, the slightly different sequences from Gibbon ape leukemia virus, Moloney leukemia virus, PSAPP alone, or a proline-rich SH3 binding sequence do not efficiently rescue RSV L-domain mutations.

Amino Acid Sequence↗

Striatal dopamine (D2) receptor availability predicts socially desirable responding.

Research in non-human primates has implicated striatal dopamine (D2) receptor function in the expression of social dominance--a fundamental component of social extraversion. We predicted that trait extraversion - indexed by the revised Eysenck Personality Questionnaire (EPQ-R) - would correlate with striatal DA (D2) receptor measures - indexed by [(11)C]-Raclopride binding potential (BP) - in 28 healthy post-menopausal females (mean age=75 years; range=58-91 years). Region of interest (ROI) and voxel-based statistical parametric mapping (SPM) analyses were performed, using a reference tissue model for [(11)C]-Raclopride. ROI analysis showed moderately significant negative correlations between extraversion and BP measures in the left caudate and between psychoticism scores and BP in the right putamen. Unexpectedly, scores on the Lie scale, a measure of socially desirable responding, were significantly and negatively correlated with BP measures in the putamen and survived Bonferroni correction on the right side. After controlling for the potential confounding of self-report bias in high Lie scorers, only the correlation between Lie scores and BP measures in the right putamen remained significant. Voxel-based analysis showed only Lie scores to be significantly and negatively correlated with BP measures in the right putamen. We explored this association further by applying an ROI-based approach to data on a previously scanned sample of young adults (n=13) and found a similar pattern of association, which achieved trend level significance in the right putamen. Although unanticipated, the relationship observed between BP measures in the right putamen and Lie scores is consistent with dopaminergic involvement in socially rewarding behaviour. How this relates to dopaminergic tone will need to be further explored.

Brain↗

CEPH maps.

There are CEPH genetic maps on each homologous human chromosome pair. Genotypes for these maps have been generated in 88 laboratories that receive DNA from a reference panel of large nuclear pedigrees/families supplied by the Centre d'Etude du Polymorphisme Humain. These maps serve as useful tools for the localization of both disease genes and other genes of interest.

Academies and Institutes↗

Spinothalamic and spinohypothalamic tract neurons in the sacral spinal cord of rats. I. Locations of antidromically identified axons in the cervical cord and diencephalon.

1. A goal of this study was to determine the sites in the diencephalon to which neurons in sacral spinal segments of rats project. Therefore, 95 neurons were recorded extracellularly in spinal segments L6-S2 of rats that were anesthetized with urethan. These neurons were activated initially antidromically with currents < or = 30 microA from a monopolar stimulating electrode placed into the contralateral posterior diencephalon. The mean +/- SE current for antidromic activation from these sites was 16 +/- 0.8 microA. These neurons were recorded in the superficial dorsal horn (4%), deep dorsal horn (89%), and intermediate zone and ventral horn (4%). 2. Systematic antidromic mapping techniques were used to map the axonal projections of 41 of these neurons within the diencephalon. Thirty-three neurons (80%) could be activated antidromically with currents < or = 30 microA only from points in the contralateral thalamus and are referred to as spinothalamic tract (STT) neurons. Eight neurons (20%) were activated antidromically with low currents from points in both the contralateral thalamus and hypothalamus, and these neurons are referred to as spinothalamic tract/ spinohypothalamic tract (STT/SHT) neurons. Three additional neurons were activated antidromically with currents < or = 30 microA only from points within the contralateral hypothalamus and are referred to as spinohypothalamic tract (SHT) neurons. The diencephalic projections of another 51 neurons were mapped incompletely. These neurons are referred to as spinothalamic/unknown (STT/ U) neurons to indicate that it was not known whether their axons ascended beyond the site in the thalamus from which they initially were activated antidromically. 3. For 31 STT neurons, the most anterior point at which antidromic activation was achieved with currents < or = 30 microA was determined. Fourteen (45%) were activated antidromically only from sites posterior to the ventrobasal complex (VbC) of the thalamus. Sixteen STT neurons (52%) were activated antidromically with low currents from sites at the level of the VbC, but not from more anterior levels. One STT neuron (3%) was activated antidromically from the anteroventral nucleus of the thalamus. 4. STT/SHT neurons were antidromically activated with currents < or = 30 microA from the medial lemniscus (ML), anterior pretectal nucleus (APt), posterior nuclear group and medial geniculate nucleus (Po/MG), and zona incerta in the thalamus and from the optic tract (OT), supraoptic decussation, or lateral area of the hypothalamus. No differences in the sites in the thalamus from which STT and STT/SHT neurons were activated antidromically were apparent. Five STT/SHT neurons (62%) were activated antidromically from points in the thalamus in the posterior diencephalon and from points in the hypothalamus at more anterior levels. Three STT/SHT neurons (38%) were activated antidromically with currents < or = 30 microA from sites in both the thalamus and hypothalamus at the same anterior-posterior level of the diencephalon. All three of these STT/SHT neurons projected to the intralaminar nuclei (parafascicular or central lateral nuclei) of the thalamus. 5. Seven STT/SHT neurons were tested for additional projections to the ipsilateral brain. Two (29%) were activated antidromically with currents < or = 30 microA and at longer latencies from sites in the ipsilateral diencephalon. One could only be activated antidromically from the hypothalamus ipsilaterally. The other was activated antidromically at progressively increasing latencies from points in the ipsilateral brain that extended as far posteriorly as the posterior pole of the MG. 6. Fifty-eight STT, STT/SHT, and STT/U neurons were classified as low-threshold (LT), wide dynamic range (WDR), or highthreshold (HT) neurons based on their responsiveness to innocuous and noxious mechanical stimuli applied to their cutaneous receptive fields.(ABSTRACT TRUNCATED)

Animals↗

Fine mapping in tomato using microsynteny with the Arabidopsis genome: the Diageotropica (Dgt) locus.

BACKGROUND: The Arabidopsis thaliana genome sequence provides a catalog of reference genes applicable to comparative microsynteny analysis of other species, facilitating map-based cloning in economically important crops. We have applied such an analysis to the tomato expressed sequence tag (EST) database to expedite high-resolution mapping of the Diageotropica (Dgt) gene within the distal end of chromosome 1 in tomato (Lycopersicon esculentum). RESULTS: A BLAST search of the Arabidopsis database with nucleotide sequences of markers that flank the tomato dgt locus revealed regions of microsynteny between the distal end of chromosome 1 in tomato, two regions of Arabidopsis chromosome 4, and one on chromosome 2. Tomato ESTs homeologous to Arabidopsis gene sequences within those regions were converted into co-dominant molecular markers via cleaved amplified polymorphic sequence (CAPS) analysis and scored against an informative backcross mapping population. Six new microsyntenic EST (MEST) markers were rapidly identified in the dgt region, two of which further defined the placement of the Dgt gene and permitted the selection of a candidate tomato bacterial artificial chromosome clone for sequence analysis. CONCLUSIONS: Microsynteny-based comparative mapping combined with CAPS analysis of recombinant plants rapidly and economically narrowed the dgt mapping region from 0.8 to 0.15 cM. This approach should contribute to developing high-density maps of molecular markers to target-specific regions for positional cloning and marker-assisted selection in a variety of plants.

Arabidopsis↗

New body surface isopotential map evaluation method to detect minor potential losses in non-Q-wave myocardial infarction.

BACKGROUND: Potential losses caused by stable non-Q-wave myocardial infarction (MI) are too small to diagnose with the use of standard ECG. The aim of the present study was to obtain accurate diagnostic criteria for this prognostically important disease with the help of body surface mapping. METHODS AND RESULTS: Body surface potentials were recorded with the use of 63 unipolar leads in 45 patients with a non-Q-wave MI (41 to 75 years old); 24 healthy adults, 42 patients with unstable angina, and 70 patients with Q-wave MI served as reference groups. Qualitative pathological features of the isopotential maps, such as onset time and site and magnitude of the first right-anterior/anterior minimum, as well as pathological negativities at that time, were defined in non-Q-wave MI cases. These features, which account for the activation sequence and the body surface projections of specific cardiac regions (Selvester classification), showed a 91% sensitivity and an 88% specificity for the detection of non-Q-wave MI. In comparison, the different departure maps (first third QRS, QRS, and QRST isoarea) resulted in less favorable specificities (50% to 58%). Concordance between the isopotential maps and the acute-phase ECG (90%), hypokinesis (64%), fixed perfusion defects (59%), and significant stenosis of the infarct-related coronary artery (87%) supported the concept that these isopotential map changes correspond to the supposed sites of MI. There were pathological features in 69% of patients with unstable angina, with similar concordances as in non-Q-wave MI. CONCLUSIONS: Isopotential maps revealed characteristic features that were suitable for the detection and localization of non-Q-wave MI in the clinical setting of unstable coronary artery disease.

Adult↗

On the design of genome mapping experiments using short synthetic oligonucleotides.

The DNA of an organism can be digested into smaller fragments, stored individually as clones in phage, for example, to create a clone library, and retrieved later, when needed. The original ordering of fragments is lost in the process of creating the library. Hence, it is important to be able to place clones in order according to their position along chromosome(s), and this process is referred to as "in vitro reconstruction" or "contig mapping" of an organismal genome. Clones in the phage library can be assigned binary call numbers by scoring each clone for hybridization (0 or 1) with a battery of short manufactured DNA sequences called synthetic oligonucleotides or with restriction enzyme digests of each clone. Those clones with similar call numbers are placed close together in the ordered library. We address the design question of how many clones and probes to use to carry out in vitro reconstruction of an organism's chromosomes. This physical mapping problem is placed in the context of coverage problems in geometrical probability. Various statistics are developed to summarize how an ordered library covers a chromosome, the extent of clone overlap, and the similarity between clone call numbers. Several tests for whether clones overlap are given, together with their power properties. A simulation study is used to determine how robust some of the tests for clone overlap are to model violations. Tables are presented for researchers to choose the number of clones and probes on the basis of both power and technical considerations surrounding the hybridization experiments.

Animals↗

The human serum amyloid A protein (SAA) superfamily gene cluster: mapping to chromosome 11p15.1 by physical and genetic linkage analysis.

The human serum amyloid A protein (SAA) family comprises a number of small, hepatically produced, differentially expressed apolipoproteins encoded by genes localized on the short arm of chromosome 11.SAA1 and SAA2 are highly related genes that together encode the acute-phase SAAs; SAA3 is a pseudogene; and SAA4 is a low-level constitutively expressed gene encoding constitutive SAA. We have used a combination of physical and genetic mapping techniques to provide evidence that the SAA gene superfamily comprises a cluster of closely linked genes localized to 11p15.1. Pulsed-field gel electrophoresis placed SAA1 to within 350 kb of the previously linked SAA2 and SAA4 genes. SAA locus-specific polymerase chain reaction amplification from a panel of somatic cell hybrids carrying defined regions of chromosome 11p mapped all four loci to 11p15.1-pter. Fluorescence in situ hybridization analysis using a cosmid probe carrying the SAA2 and SAA4 genes refined the localization of these genes (and SAA1) to 11p15.1. To order SAA3 on the genetic map, a highly polymorphic (CA)n dinucleotide repeat within SAA3 was typed through the CEPH reference families. In accordance with the physical localization of SAAs 1, 2, and 4, SAA3 maps to the 11p15.1 region proximal to the parathyroid hormone (PTH) locus (theta = 0.02; lod = 12.020) and distal to D11S455 (theta = 0.058, lod = 8.274). To provide further evidence of an SAA superfamily gene cluster, an NcoI restriction fragment length polymorphism in the SAA2 gene was also typed through the CEPH reference panel.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosome Mapping↗

A systematic approach to simulating metabolism in computational toxicology. I. The TIMES heuristic modelling framework.

Designing biologically active chemicals and managing their risks requires a holistic perspective on the chemical-biological interactions that form the basis of selective toxicity. The balance of therapeutic and adverse outcomes for new drugs and pesticides is managed by shaping the probabilities for transport, metabolism, and molecular initiating events. For chemicals activated as well as detoxified by metabolism, selective toxicity may be considered in terms of relative probabilities, which shift dramatically across species as well as within a population, depending on many factors. The complexity in toxicology that results from metabolism has been troublesome in QSAR research because the parent structure is less relevant to predicting ultimate effects and finding reference species/conditions for metabolic rates seems hopeless. Even the complexity of comparative xenobiotic metabolism itself seems paradoxical in light of the evidence of highly conserved catabolic processes across species. Clearly, predicting the role of metabolism in selective toxicity and adverse health outcomes requires a probabilistic framework for deterministic models as well as the many factors shaping the metabolic probability distributions under specific conditions. This paper presents a tissue metabolism simulator (TIMES), which uses a heuristic algorithm to generate plausible metabolic maps from a comprehensive library of biotransformations and abiotic reactions and estimates for system-specific transformation probabilities. The transformation probabilities can be calibrated to specific reference conditions using transformation rate information from systematic testing. In the absence of rate data, a combinatorial algorithm is used to translate known metabolic maps taken from reference systems into best-fit transformation probabilities. Finally, toxicity test data itself can be used to shape the transformation probabilities for toxicity pathways in which the metabolic activation is the rate-limiting process leading to a toxic effect. The conceptual approach for metabolic simulation will be presented along with practical uses in forecasting plausible activated metabolites.

Animals↗

Immunological characterization of microtubule-associated proteins specific for the immature brain.

Immunoblotting analysis was used to detect the microtubule-associated proteins present at different stages of rat brain development. Polyclonal antibodies were raised against the two main adult brain microtubule-associated proteins: MAP-2 (300 kDa) and TAU (60-70 kDa). Whatever the stage of development, anti-MAP-2 serum detected high molecular mass proteins and at immature stages a protein of 62 kDa. This protein which has previously been referred to as 'young TAU slow' is, therefore, immunologically related to MAP-2. The anti-TAU serum (but not the anti-MAP-2 serum) detected at immature stages of development a 48 kDa protein which also disappears at adulthood. This 48 kDa entity which has been referred to as 'young TAU fast' is progressively replaced by the closely spaced bands (60-70 kDa) of adult TAU proteins. The 62 and 48 kDa proteins appear therefore to be immunologically distinct and represent two microtubule-associated proteins specific to the immature brain.

Animals↗

Averaging of spectral power and phase via vector diagram best fits without reference electrode or reference channel.

A method is proposed to average results of Fourier analysis over epochs without assigning zero amplitude values to any electrode or zero phase values to any channel. The Fourier sine and cosine values of each electrode define its entry location into a vector diagram for the frequency component. The entry constellations thus formed are translated so that the mean of all entries (the virtual average reference which is the location of best fit) is at the centre of each constellation, and then they are rotated around the means into angles of best fit so that the sum of the squared distances between corresponding entries is minimal. The method leads to non-ambiguous mean results, with variance information for all recording points. Approaches for the assessment of the constellations, their transformation into field maps, and the problems with conventional phase measurements vs. real electrodes are discussed. The virtual average reference (spatial high pass filter) is proposed for assessing the time sequence (phase differences) between entry points, thus describing the internal structure of the constellations without bias and without reference to a zero phase point. Comparison of voltage and current density result constellations and consideration of reference-independent descriptors of the scalp field potential maps support the validity of the average reference for the approach.

Electroencephalography↗

Corticopulvinar connections of areas V5, V4, and V3 in the macaque monkey: a dual model of retinal and cortical topographies.

The connection zones of cortical areas V3, V4, and V5 (MT) with the thalamic pulvinar nucleus in the macaque monkey were identified. A combination of single- and dual-tracer techniques was used to study their topography and to establish whether these zones occupy separate or overlapping pulvinar territories. In each case, the retinotopic distribution of tracer in the pulvinar was charted by reference to its parallel distribution within the maps of cortical areas V1 and V2. Each of the areas V3, V4, and V5 were found to connect with both the 1° and the 2° maps located within the inferior and lateral pulvinar nuclei and to respect the previously identified topographies of these maps. However, V5 connects to a narrow zone lining the rostrolateral margin of the lateral and inferior pulvinar and V4 to a broader zone within the body of these two nuclei, which is adjacent to but separate from the V5 zone; the V3 zone overlaps both. Focal injections into cortex produce columns of pulvinar label whose trajectory defines a line of isorepresentation. The lines of isorepresentation in the 1° and 2° maps are approximately linear and parallel and adopt a rostrolateral to caudomedial axis; in the 1° map, this axis is roughly perpendicular to the facet of the inferior pulvinar that lies adjacent to the lateral geniculate nucleus. The connections of V5 and V4 can be modelled as successive zones along the axis of isorepresentation, with registered visual topographies. The scheme is extended by existing reports that inferotemporal cortex connects to the caudomedial pole of this axis-reflecting an occipitotemporal cortical gradient, in that V1 and other prestriate areas, e.g., V3, connect to the opposite pole. Thus a simple model of the mapped volume in the pulvinar arises, in which a unidimensional cortical topography is represented orthogonally to retinal topography. Adjoining this volume medially, within the inferior and medial pulvinar, is a second, heavier zone of V5 connectivity, which is poorly topographic. Both the medial and the rostrolateral zones of V5 connectivity may overlap with previously identified regions of tectal input to the pulvinar.

Animals↗

An updated two-dimensional gel database of rat liver proteins useful in gene regulation and drug effect studies.

We have improved upon the reference two-dimensional (2-D) electrophoretic map of rat liver proteins originally published in 1991 (N. L. Anderson et al., Electrophoresis 1991, 12, 907-930). A total of 53 proteins (102 spots) are now identified, many by microsequencing. In most cases, spots cut from wet, Coomassie Blue stained 2-D gels were submitted to internal tryptic digestion [2], and individual peptides, separated by high-performance liquid chromatography (HPLC), were sequenced using a Perkin-Elmer 477A sequenator. Additional spots were identified using specific antibodies.

Animals↗

Global protein expression pattern of Bradyrhizobium japonicum bacteroids: a prelude to functional proteomics.

As a prelude to using functional proteomics towards understanding the process of symbiotic nitrogen fixation between the legume soybean and the soil bacteria Bradyrhizobium japonicum, we examined the total protein expression pattern of the nodule bacteria, often referred to as bacteroids. A partial proteome map was constructed by separating the total bacteroid proteins using high-resolution 2-DE. Of the several hundred protein spots analyzed using PMF, 180 spots were tentatively identified by searching the available database for B. japonicum, (http://www.kazusa.or.jp/index.html). The data showed that the bacteroid expressed a dominant and elaborate protein network for nitrogen and carbon metabolism, which is closely dependent on the plant supplied metabolites, and seems aptly supported by a selective group of bacteroid transporter proteins. However, they seem to lack a defined fatty acid and nucleic acid metabolism. Interestingly, the proteins related to protein synthesis, scaffolding and degradation were among the most predominant spots of the bacteroid proteome. In addition, several proteins, which showed fairly good expression, were identified to be involved with cellular detoxification, stress regulation and signaling communication components. This preliminary proteomic data matches very well with several biochemical and genetic reports, and clearly shows the inter-connection between several metabolic pathways that meet the needs of the bacteroid. It is expected that in the future this will allow us to develop testable hypotheses about the roles of several of these proteins in context to the metabolic pathway connections and metabolite fluxes.

Amino Acids↗