Mutations within hox genes in Drosophila transform defined segments of the body into the character of an adjacent segments. Homologous genes there are in vertebrates, where it has been possible to mutate them, shifts in morphological character have also been produced.

The discovery of the first HOX cluster outside Drosophila causes great excitement, and it was proposed that the homeobox would become a "Rosetta stone" for the study of animal development, enabling us to read the epigenetic code of other animals on the basis of our understanding of Drosophila (Slack, Holland, Graham, 1993). It is possible that this HOX-based epigenetic code is very ancient and was in place in the common ancestor of all modern animals. According to Slack, Holland and Graham, this character should be adopted as the defining character, or synapomorphy, of the kingdom Animalia.

Nowadays homeobox genes were found for species of main invertebrate and vertebrate taxa. It is known that these genes play key role in time and space orchestration of genome expression during development. Members of Hox complexes are of particular importance in specifying the overall animal body plan, and have been the objects of intensive study. For these reasons, the homeobox containing genes are a natural choice for the subject matter of a database concerned with gene function in development at multiple levels. A further advantage of using the homeobox as a criterion for inclusion in the database is that its presence is an unambiguous sequence-based criterion which indicates a developmentally relevant gene, although not all such genes contain a homeobox domain.

The long-term goal of HOX Pro is the reconstruction and prediction of functional genetic regulatory pathways from all relevant biological assays. These include not only sequence data but also information about protein binding, expression patterns, and so on. We hope to integrate the molecular aspects of modern developmental biology by utilizing the information pathways that run from sequence data to developing organs and tissues.

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Partly supported by:

• The "HUMAN GENOME" (Russian Academy of Sciences), Project "Data bank of regulatory regions of human/mammalian homeo box-containing genes and computer analysis of the regulatory regions" (1994);
• The "Russian Foundation for Basic Researches", project "Simulations of the processes in evolutionary and ecological physiology" (1994-1997);
• The "Russian Foundation for Basic Researches", project "Phylogenetic analysis of the HOX network structure as synapomorphy of the kingdom Animalia" (1996-1997);
• The INTAS foundation, project "Application of new evolutionary computation techniques - the Mobile Genetic Elements (MGE) in cognitive approaches to registration, classification and segmentation of series of biological and medical images" (1999-2001);
• The "Russian Foundation for Basic Researches", project "Molecular-Physiological aspects of evolution of the genetic network controlling embryonic segmentation of species of Drosophilidae" (2000-2002).

HOX-Pro

Keywords: genes, clusters, maps, homeobox-genes, hox-genes, antennapedia-like genes, msx-genes, evx-genes, paired-like, pax, genetic networks, boolean networks, wired diagrams, crossregulatory, autoregulatory, regulatory connections, transcription regulation, transcription factors, retinoic acid, homeodomain, zinc-finger, binding sites, cis-regulatory, RARE, HDRE, enhancers, promoters, transposons, alu, expression, pattern, rhombdomere, metamerization, segmentation, Drosophila melanogaster, Caenorhabditis elegans, nematode, Strongylocentrotus purpuratus, sea urchins, Xenopus laevis, annelids, leech, crustacean, arthropods, amphioxus, lamprey, teleost, pufferfish, fugu, zebrafish, invertebrate and vertebrate development, phylogeny, evolution