Sufficient knowledge of molecular and genetic interactions, which comprise the entire basis of the functioning of living systems, is one of the necessary requirements for successfully answering almost any research question in the field of biology and medicine. To date, more than 24 million scientific papers can be found in PubMed, with many of them containing descriptions of a wide range of biological processes. The analysis of such tremendous amounts of data requires the use of automated text-mining approaches. Although a handful of tools have recently been developed to meet this need, none of them provide error-free extraction of highly detailed information. The ANDSystem package was developed for the reconstruction and analysis of molecular genetic networks based on an automated text-mining technique. It provides a detailed description of the various types of interactions between genes, proteins, microRNA's, metabolites, cellular components, pathways and diseases, taking into account the specificity of cell lines and organisms. Although the accuracy of ANDSystem is comparable to other well known text-mining tools, such as Pathway Studio and STRING, it outperforms them in having the ability to identify an increased number of interaction types. The use of ANDSystem, in combination with Pathway Studio and STRING, can improve the quality of the automated reconstruction of molecular and genetic networks. ANDSystem should provide a useful tool for researchers working in a number of different fields, including biology, biotechnology, pharmacology and medicine.

The PDBSite database provides comprehensive structural and functional information on various protein sites (post-translational modification, catalytic active, organic and inorganic ligand binding, protein–protein, protein–DNA and protein–RNA interactions) in the Protein Data Bank (PDB). The PDBSite is available online at http://wwwmgs.bionet.nsc.ru/mgs/gnw/pdbsite/. It consists of functional sites extracted from PDB using the SITE records and of an additional set containing the protein interaction sites inferred from the contact residues in heterocomplexes. The PDBSite was set up by automated processing of the PDB. The PDBSite database can be queried through the functional description and the structural characteristics of the site and its environment. The PDBSite is integrated with the PDBSiteScan tool allowing structural comparisons of a protein against the functional sites. The PDBSite enables the recognition of functional sites in protein tertiary structures, providing annotation of function through structure. The PDBSite is updated after each new PDB release.

Eight fatal cases of tick-borne encephalitis with unusual hemorrhagic syndrome were identified in 1999 in the Novosibirsk Region, Russia. To study these strains, we sequenced cDNA fragments of protein E gene from six archival formalin-fixed brain samples. Phylogenetic analysis showed tick-borne encephalitis variants clustered with a Far Eastern subtype (homology 94.7%) but not with the Siberian subtype (82%).

PDBSiteScan is a web-accessible program designed for searching three-dimensional (3D) protein fragments similar in structure to known active, binding and posttranslational modification sites. A collection of known sites we designated as PDBSite was set up by automated processing of the PDB database using the data on site localization in the SITE field. Additionally, protein–protein interaction sites were generated by analysis of atom coordinates in heterocomplexes. The total number of collected sites was more than 8100; they were assigned to more than 80 functional groups. PDBSiteScan provides automated search of the 3D protein fragments whose maximum distance mismatch (MDM) between N, Cα and C atoms in a fragment and a functional site is not larger than the MDM threshold defined by the user. PDBSiteScan requires perfect matching of amino acids. PDBSiteScan enables recognition of functional sites in tertiary structures of proteins and allows proteins with functional information to be annotated. The program PDBSiteScan is available at http://wwwmgs.bionet.nsc.ru/mgs/systems/fastprot/pdbsitescan.html.

Consideration of tissue-specific gene expression in reconstruction and analysis of molecular genetic networks is necessary for a proper description of the processes occurring in a specified tissue. Currently, there are a number of computer systems that allow the user to reconstruct molecular-genetic networks using the data automatically extracted from the texts of scientific publications. Examples of such systems are STRING, Pathway Commons, MetaCore and Ingenuity. The MetaCore and Ingenuity systems permit taking into account tissue-specific gene expression during the reconstruction of gene networks. Previously, we developed the ANDSystem tool, which also provides an automated extraction of knowledge from scientific texts and allows the reconstruction of gene networks. The main difference between our system and other tools is in the different types of interactions between objects, which makes the ANDSystem complementary to existing well-known systems. However, previous versions of the ANDSystem did not contain any information on tissue-specific expression. A new version of the ANDSystem has been developed. It offers the reconstruction of associative gene networks while taking into account the tissue-specific gene expression. The ANDSystem knowledge base features information on tissue-specific expression for 272 tissues. The system allows the reconstruction of combined gene networks, as well as performing the filtering of genes from such networks using the information on their tissue-specific expression. As an example of the application of such filtering, the gene network of the extrinsic apoptotic signaling pathway was analyzed. It was shown that considering different tissues can lead to changes in gene network structure, including changes in such indicators as betweenness centrality of vertices, clustering coefficient, network centralization, network density, etc. The consideration of tissue specificity can play an important role in the analysis of gene networks, in particular solving the problem of finding the most significant central genes. Thus, the new version of ANDSystem can be employed for a wide range of tasks related to biomedical studies of individual tissues. It is available at http://www-bionet.sscc.ru/and/cell /.