Development of Tools for Tomato Functional Genomics: Application to Analysis of Fruit Development, Responses to Pathogens, and Genome Synteny with Arabidopsis

番茄长期以来一直是植物遗传学、发育、病理学和生理学的模式系统，积累了大量关于这种重要经济生物的生物学信息。近年来，番茄生物学研究最广泛的方面包括肉质果实的发育和成熟，以及对微生物病原体侵染的反应特性。尽管拟南芥已经超过了一些植物系统，成为基础植物生物学研究的模型，但番茄作为实验生物的选择，在果实成熟和病原菌响应方面继续蓬勃发展。就果实发育而言，这仅仅是因为导致番茄和许多其他经济和营养重要物种心皮急剧扩张和成熟的发育程序在拟南芥中没有发生。在植物防御方面，几十年来对番茄的应用和基础研究已经形成了对多种病原物的反应特征。在许多情况下，这导致了授予一般或病原体特异性抗性的基因座的鉴定和基因特征。此外，番茄的许多实验工具和特性本身也使其成为一个优秀的模式系统，包括：广泛的种质收集；大量的自然、诱导和转基因突变和遗传变体；常规转化技术；密集的RFLP图谱；大量的cdna和基因组文库；较小的基因组；相对较短的生命周期；以及易于生长和维护。在水果生物学和防御反应方面的密集研究努力，以及使番茄成为特别有吸引力的模型系统的可用工具，导致了许多重要的最近发现。在植物生物学领域产生广泛影响的具体亮点包括：通过反义/正义技术控制基因表达；影响果实发育和成熟的众多基因的功能表征；影响对病原菌攻击的敏感性或反应的基因的转基因分析；以及分离出比任何其他植物更多的抗病基因。该项目涉及开发一套用于番茄功能基因组学的综合实验工具。开发的资源将用于扩大对果实发育和对病原体感染反应的分子遗传事件的了解，并将提供给研究界用于分析各种植物生物现象。具体目标包括：(1)建立番茄EST(表达序列标签)数据库，重点关注果实发育成熟和病原菌攻击组织中表达的序列；(2)全基因组分析果实发育和成熟以及病原菌侵染响应过程中的基因表达；以及(3)开发番茄-拟南芥共轭图谱，该图谱将被该小组成员使用并公开用于靶基因分离、候选基因鉴定以及基因组组织和进化分析。

Tomato has long served as a model system for plant genetics, development, pathology, and physiology, which has resulted in an accumulation of substantial information regarding the biology of this economically important organism. In recent years, the most widely studied aspects of tomato biology include development and ripening of fleshy fruits and characterization of responses to infection by microbial pathogens. Although Arabidopsis has surpassed some plant systems as a model for basic plant biology research, the areas of fruit ripening and pathogen response continue to thrive with tomato as the experimental organism of choice. In the case of fruit development, this is simply due to the fact that the developmental program which results in the dramatic expansion and ripening of carpels in tomato and in many other economically and nutritionally important species does not occur in Arabidopsis. With regard to plant defense, decades of applied and basic research on tomato have resulted in characterization of responses to numerous disease agents. In many cases, this has led to the identification and genetic characterization of loci that confer general or pathogen-specific resistance. In addition, many experimental tools and features of tomato make it an excellent model system in its own right including: extensive germplasm collections; numerous natural, induced and transgenic mutants and genetic variants; routine transformation technology; a dense RFLP map; numerous cDNA and genomic libraries; a small genome; relatively short life-cycle; and ease of growth and maintenance. The intense research efforts in fruit biology and defense responses and the available tools that make tomato an especially attractive model system have resulted in many important recent discoveries. Specific highlights which have had a broad impact on the field of plant biology include: control of gene expression by antisense/sense technology; functional characterization of numerous genes influencing fruit development and ripening; transgenic analysis of genes which impact susceptibility or response to pathogen attack; and isolation of more disease resistance genes than any other plant species.This project involves development of an integrated set of experimental tools for use in tomato functional genomics. The resources developed will be used to expand understanding of the molecular genetic events underlying fruit development and the response to pathogen infection and will be made available to the research community for analysis of diverse plant biological phenomena. Specific objectives include: (1) development of a tomato EST (Expressed Sequence Tag) database with emphasis on sequences expressed during fruit development and maturation and in pathogen-challenged tissues; (2) genome-wide gene expression analyses during fruit development and ripening and in response to pathogen infection; and (3) development of a tomato-Arabidopsis synteny map which will be used by members of this group and made publicly available for target gene isolation, candidate gene identification, and analysis of genome organization and evolution.