Department of Medicine, Vanderbilt University, Nashville, TN 37232-0275, USA.
BMC Bioinformatics. 2009 Dec 14;10:420. doi: 10.1186/1471-2105-10-420.
Widespread use of high-throughput techniques such as microarrays to monitor gene expression levels has resulted in an explosive growth of data sets in public domains. Integration and exploration of these complex and heterogeneous data have become a major challenge.
The EXALT (EXpression signature AnaLysis Tool) online program enables meta-analysis of gene expression profiles derived from publically accessible sources. Searches can be executed online against two large databases currently containing more than 28,000 gene expression signatures derived from GEO (Gene Expression Omnibus) and published expression profiles of human cancer. Comparisons among gene expression signatures can be performed with homology analysis and co-expression analysis. Results can be visualized instantly in a plot or a heat map. Three typical use cases are illustrated.
The EXALT online program is uniquely suited for discovering relationships among transcriptional profiles and searching gene expression patterns derived from diverse physiological and pathological settings. The EXALT online program is freely available for non-commercial users from http://seq.mc.vanderbilt.edu/exalt/.
高通量技术（如微阵列）的广泛应用，使得公共领域中的基因表达数据集呈爆炸式增长。这些复杂和异构数据的整合和探索已成为一个主要挑战。
EXALT（表达谱分析工具）在线程序可用于对公共可访问资源中得出的基因表达谱进行荟萃分析。可以在线搜索目前包含来自 GEO（基因表达综合数据库）和已发表的人类癌症表达谱的超过 28000 个基因表达特征的两个大型数据库。可以进行基因表达特征之间的同源性分析和共表达分析。结果可以立即以图形或热图的形式可视化。展示了三个典型的应用案例。
EXALT 在线程序非常适合发现转录谱之间的关系，并搜索来自不同生理和病理环境的基因表达模式。EXALT 在线程序可免费供非商业用户从 http://seq.mc.vanderbilt.edu/exalt/ 使用。
