RESUMO
The rice species Oryza sativa is considered to be a model plant because of its small genome size, extensive genetic map, relative ease of transformation and synteny with other cereal crops. Here we report the essentially complete sequence of chromosome 1, the longest chromosome in the rice genome. We summarize characteristics of the chromosome structure and the biological insight gained from the sequence. The analysis of 43.3 megabases (Mb) of non-overlapping sequence reveals 6,756 protein coding genes, of which 3,161 show homology to proteins of Arabidopsis thaliana, another model plant. About 30% (2,073) of the genes have been functionally categorized. Rice chromosome 1 is (G + C)-rich, especially in its coding regions, and is characterized by several gene families that are dispersed or arranged in tandem repeats. Comparison with a draft sequence indicates the importance of a high-quality finished sequence.
Assuntos
Cromossomos de Plantas/genética , Genoma de Planta , Oryza/genética , Mapeamento Físico do Cromossomo , Arabidopsis/genética , Composição de Bases , Cloroplastos/genética , Biologia Computacional , Mapeamento de Sequências Contíguas , Elementos de DNA Transponíveis/genética , Éxons/genética , Etiquetas de Sequências Expressas , Genes de Plantas/genética , Hibridização in Situ Fluorescente , Íntrons/genética , Dados de Sequência Molecular , Família Multigênica/genética , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA , Homologia de Sequência , Sequências de Repetição em Tandem/genéticaRESUMO
An extensive effort of the International Rice Genome Sequencing Project (IRGSP) has resulted in rapid accumulation of genome sequence, and >137 Mb has already been made available to the public domain as of August 2001. This requires a high-throughput annotation scheme to extract biologically useful and timely information from the sequence data on a regular basis. A new automated annotation system and database called Rice Genome Automated Annotation System (RiceGAAS) has been developed to execute a reliable and up-to-date analysis of the genome sequence as well as to store and retrieve the results of annotation. The system has the following functional features: (i) collection of rice genome sequences from GenBank; (ii) execution of gene prediction and homology search programs; (iii) integration of results from various analyses and automatic interpretation of coding regions; (iv) re-execution of analysis, integration and automatic interpretation with the latest entries in reference databases; (v) integrated visualization of the stored data using web-based graphical view. RiceGAAS also has a data submission mechanism that allows public users to perform fully automated annotation of their own sequences. The system can be accessed at http://RiceGAAS.dna.affrc.go.jp/.
