ASPicDB: a database resource for alternative splicing analysis.

MOTIVATION: Alternative splicing has recently emerged as a key mechanism responsible for the expansion of transcriptome and proteome complexity in human and other organisms. Although several online resources devoted to alternative splicing analysis are available they may suffer from limitations related both to the computational methodologies adopted and to the extent of the annotations they provide that prevent the full exploitation of the available data. Furthermore, current resources provide limited query and download facilities. RESULTS: ASPicDB is a database designed to provide access to reliable annotations of the alternative splicing pattern of human genes and to the functional annotation of predicted splicing isoforms. Splice-site detection and full-length transcript modeling have been carried out by a genome-wide application of the ASPic algorithm, based on the multiple alignments of gene-related transcripts (typically a Unigene cluster) to the genomic sequence, a strategy that greatly improves prediction accuracy compared to methods based on independent and progressive alignments. Enhanced query and download facilities for annotations and sequences allow users to select and extract specific sets of data related to genes, transcripts and introns fulfilling a combination of user-defined criteria. Several tabular and graphical views of the results are presented, providing a comprehensive assessment of the functional implication of alternative splicing in the gene set under investigation. ASPicDB, which is regularly updated on a monthly basis, also includes information on tissue-specific splicing patterns of normal and cancer cells, based on available EST sequences and their library source annotation. AVAILABILITY: www.caspur.it/ASPicDB

Statistical assessment of functional categories of genes deregulated in pathological conditions by using microarray data.

MOTIVATION: A major challenge in current biomedical research is the identification of cellular processes deregulated in a given pathology through the analysis of gene expression profiles. To this end, predefined lists of genes, coding specific functions, are compared with a list of genes ordered according to their values of differential expression measured by suitable univariate statistics. RESULTS: We propose a statistically well-founded method for measuring the relevance of predefined lists of genes and for assessing their statistical significance starting from their raw expression levels as recorded on the microarray. We use prediction accuracy as a measure of relevance of the list. The rationale is that a functional category, coded through a list of genes, is perturbed in a given pathology if it is possible to correctly predict the occurrence of the disease in new subjects on the basis of the expression levels of the genes belonging to the list only. The accuracy is estimated with multiple random validation strategy and its statistical significance is assessed against a couple of null hypothesis, by using two independent permutation tests. The utility of the proposed methodology is illustrated by analyzing the relevance of Gene Ontology terms belonging to biological process category in colon and prostate cancer, by using three different microarray data sets and by comparing it with current approaches. AVAILABILITY: Source code for the algorithms is available from author upon request. SUPPLEMENTARY INFORMATION: Colon cancer data set and a complete description of experimental results are available at: ftp://bioftp:76bioftpxxx@marx.ba.issia.cnr.it/supp-info.htm.

PLANT-PIs: a database for plant protease inhibitors and their genes.

PLANT-PIs is a database developed to facilitate retrieval of information on plant protease inhibitors (PIs) and related genes. For each PI, links to sequence databases are reported together with a summary of the functional properties of the molecule (and its mutants) as deduced from literature. PLANT-PIs contains information for 351 plant PIs, plus several isoinhibitors. The database is accessible at http://bighost.area.ba.cnr.it/PLANT-PIs.

Structural and functional features of eukaryotic mRNA untranslated regions.

The crucial role of the non-coding portion of genomes is now widely acknowledged. In particular, mRNA untranslated regions are involved in many post-transcriptional regulatory pathways that control mRNA localization, stability and translation efficiency. We review in this paper the major structural and compositional features of eukaryotic mRNA untranslated regions and provide some examples of bioinformatic analyses for their functional characterization.

PLMItRNA, a database for mitochondrial tRNA genes and tRNAs in photosynthetic eukaryotes.

The PLMItRNA database for mitochondrial tRNA molecules and genes in VIRIDIPLANTAE: (green plants) [Volpetti,V., Gallerani,R., DeBenedetto,C., Liuni,S., Licciulli,F. and Ceci,L.R. (2000) Nucleic Acids Res., 28, 159-162] has been enlarged to include algae. The database now contains 436 genes and 16 tRNA entries relative to 25 higher plants, eight green algae, four red algae (RHODOPHYTAE:) and two STRAMENOPILES: The PLMItRNA database is accessible via the WWW at http://bio-www.ba.cnr.it:8000/PLMItRNA.

Update of AMmtDB: a database of multi-aligned metazoa mitochondrial DNA sequences.

The AMmtDB database (http://bio-www.ba.cnr.it:8000/srs6/ ) has been updated by collecting the multi-aligned sequences of Chordata mitochondrial genes coding for proteins and tRNAs. The genes coding for proteins are multi-aligned based on the translated sequences and both the nucleotide and amino acid multi-alignments are provided. AMmtDB data selected through SRS can be viewed and managed using GeneDoc or other programs for the management of multi-aligned data depending on the user's operative system. The multiple alignments have been produced with CLUSTALW and PILEUP programs and then carefully optimized manually.

MitBASE : a comprehensive and integrated mitochondrial DNA database. The present status.

MitBASE is an integrated and comprehensive database of mitochondrial DNA data which collects, under a single interface, databases for Plant, Vertebrate, Invertebrate, Human, Protist and Fungal mtDNA and a Pilot database on nuclear genes involved in mitochondrial biogenesis in Saccharomyces cerevisiae. MitBASE reports all available information from different organisms and from intraspecies variants and mutants. Data have been drawn from the primary databases and from the literature; value adding information has been structured, e.g., editing information on protist mtDNA genomes, pathological information for human mtDNA variants, etc. The different databases, some of which are structured using commercial packages (Microsoft Access, File Maker Pro) while others use a flat-file format, have been integrated under ORACLE. Ad hoc retrieval systems have been devised for some of the above listed databases keeping into account their peculiarities. The database is resident at the EBI and is available at the following site: http://www3.ebi.ac.uk/Research/Mitbase/mitbas e.pl. The impact of this project is intended for both basic and applied research. The study of mitochondrial genetic diseases and mitochondrial DNA intraspecies diversity are key topics in several biotechnological fields. The database has been funded within the EU Biotechnology programme.

PLMItRNA, a database for tRNAs and tRNA genes in plant mitochondria: enlargement and updating.

The current version of PLMItRNA has been realized to constitute a database for tRNA molecules and genes identified in the mitochondria of all green plants ( Viridiplantae ). It is the enlargement of a previous database originally restricted to seed plants [Ceci,L.R., Volpicella,M., Liuni,S., Volpetti,V., Licciulli,F. and Gallerani,R. (1999) Nucleic Acids Res., 27, 156-157]. PLMItRNA reports information and multialignments on 254 genes and 16 tRNA molecules detected in 25 higher plants (one bryophyta and 24 vascular plants) and seven green algae. PLMItRNA is accessible via the WWW at http://bio-WWW.ba.cnr.it:8000/srs6/

MitoNuc and MitoAln: two related databases of nuclear genes coding for mitochondrial proteins.

Mitochondria, besides their central role in energy metabolism, have recently been found to be involved in a number of basic processes of cell life and to contribute to the pathogenesis of many degenerative diseases. All functions of mitochondria depend on the interaction of nuclear and organellar genomes. Mitochondrial genomes have been extensively sequenced and analysed and the data collected in several specialised databases. In order to collect information on nuclear coded mitochondrial proteins we developed MitoNuc and MitoAln, two related databases containing, respectively, detailed information on sequenced nuclear genes coding for mitochondrial proteins in Metazoa and yeast, and the multiple alignments of the relevant homologous protein coding regions. MitoNuc and MitoAln retrieval through SRS at http://bio-www.ba.cnr.it:8000/srs6/ can easily allow the extraction of sequence data, subsequences defined by specific features and nucleotide or amino acid multiple alignments.

UTRdb and UTRsite: specialized databases of sequences and functional elements of 5' and 3' untranslated regions of eukaryotic mRNAs.

The 5' and 3' untranslated regions of eukaryotic mRNAs may play a crucial role in the regulation of gene expression controlling mRNA localization, stability and translational efficiency. For this reason we developed UTRdb, a specialized database of 5' and 3' untranslated sequences of eukaryotic mRNAs cleaned from redundancy. UTRdb entries are enriched with specialized information not present in the primary databases including the presence of nucleotide sequence patterns already demonstrated by experimental analysis to have some functional role. All these patterns have been collected in the UTRsite database so that it is possible to search any input sequence for the presence of annotated functional motifs. Furthermore, UTRdb entries have been annotated for the presence of repetitive elements. All internet resources implemented for retrieval and functional analysis of 5' and 3' untranslated regions of eukaryotic mRNAs are accessible at http://bigarea.area.ba.cnr.it:8000/EmbIT/UTRH ome/

Update of KEYnet: a gene and protein names database for biosequences functional organisation.

KEYnet is a database where gene and protein names are hierarchically structured. Particular care has been devoted to the search and organisation of synonyms. The structuring is based on biological criteria in order to assist the user in data search and to minimise the risk of information loss. Links to the EMBL data library by the entry name and the accession number are implemented. KEYnet is available through the WWW at the following site: http://www.ba.cnr.it/keynet.html

Analysis of oligonucleotide AUG start codon context in eukariotic mRNAs.

The AUG start codon context features have been investigated by analyzing eukaryotic mRNAs belonging to various taxonomic groups. The functional relevance of each specific position surrounding the AUG start codon has been established as a function of the measured shift between base composition observed at that particular position, and base composition averaged over all the 5'untranslated regions. A more detailed analysis carried out on human genes belonging to different isochores showed significant isochore-specific fea-tures that cannot be explained only by a mutational bias effect. The most represented heptamers spanning from position -3 to +4 with respect to the initiator AUG have been determined for mRNAs belonging to different taxonomic groups and a web page utility has been set up (http://bigarea.area.ba.cnr.it:8000/BioWWW/ATG.html) to determine the relative abundance of a user submitted oligonucleotide context in a given species or taxon.

KEYnet: a keywords database for biosequences functional organization.

KEYnet is a database where gene and protein names are hierarchically structured. Particular care has been devoted to the search and organisation of synonyms. The structuring is based on biological criteria in order to assist the user in the data search and to minimise the risk of loss of information. Links to the EMBL data library by the entry name and the accession number have been implemented. KEYnet is available through the World Wide Web at the following site: http://www.ba.cnr.it/keynet.html. Recently KEYnet has incorporated specific gene name classifications, which can be browsed starting from the above-mentioned KEYnet home page: the Mitochondrial Gene Names classification and the Rat Gene Names classification. KEYnet database has also been structured in a flatfile format and can be queried through SRS (http://bio-www.ba.cnr.t:8000/srs).

Update of AMmtDB: a database of multi-aligned metazoa mitochondrial DNA sequences.

The present paper describes AMmtDB, a database collecting the multi-aligned sequences of vertebrate mitochondrial genes coding for proteins and tRNAs, as well as the multiple alignment of the mammalian mtDNA main regulatory region (D-loop) sequences. The genes coding for proteins are multi-aligned based on the translated sequences and both the nucleotide and amino acid multi-alignments are provided. As far as the genes coding for tRNAs are concerned, the multi-alignments based on the primary and the secondary structures are both provided; for the mammalian D-loop multi-alignments we report the conserved regions of the entire D-loop (CSB1, CSB2, CSB3, the central region, ETAS1 and ETAS2) as defined by Sbisà et al. [ Gene (1997), 205, 125-140). A flatfile format for AMmtDB has been designed allowing its implementation in SRS (http://bio-www.ba.cnr.it:8000/BioWWW/#AMMTDB ). Data selected through SRS can be managed using GeneDoc or other programs for the management of multi-aligned data depending on the user's operative system. The multiple alignments have been produced with CLUSTALV and PILEUP programs and then carefully optimized manually.

PLMItRNA, a database for higher plant mitochondrial tRNAs and tRNA genes.

The PLMItRNA database contains information and multialignments of tRNA genes and molecules detected in higher plant mitochondria. It has been developed from a previous compilation of higher plant mitochondrial tRNA genes [Sagliano,A., Volpicella,M., Gallerani,R. and Ceci,L.R. (1998) Nucleic Acids Res., 26, 154-155] and implemented with data and sequences of tRNA molecules retrieved from the literature. The current version of the database reports information on 171 genes and 16 tRNA molecules from 24 plants. PLMItRNA is accessible via WWW at http://bio-www.ba.cnr.it:8000/srs/

The mitBASE human dataset structure.

MitBASE is a comprehensive and integrated mitochondrial genome database funded within the EU BIOTECH PROGRAM. It is a project for the development and implementation of an integrated and comprehensive database of mitochondrial data which will collect all available information from different organisms and from intraspecies variants and mutants. The present paper describes the structure of the Human dataset in mitBASE where human molecular data are distinguished from clinical and pathological data. MitBASE home page address is: http://www.ebi.ac.uk/htbin/Mitbase/mitb ase.pl