16 Current Genomics, 2009, Vol. 10, No. 1 Database (http://planttfdb.cbi.pku.edu.cn), gene structure, annotation, protein sequence features, 3D structure, ortholog, expression, and sequence. This is a great database but its weaknesses are that it is only for one plant species and the last update for the database was in 2006. Overall it would be considered an effective database used for rice research. CONCLUSION TFs play an important role gene expression in plants and other organisms. TFs have an active role in initiating the transcription process as well as regulating the development and response to environmental signals throughout the life of the organism. TFs trigger cascades of biochemical reactions altering the gene expression profile of a plant cell. In plants, especially, it is important to understand how TFs binding along with gene expression synchronize downstream chemi- cal reactions. These reactions help plants respond to the chal- lenging environmental conditions since plants are sessile and cannot escape from environmental stresses. TF databases are surely a valuable tool for plant biologists to study plant physiology, plant developmental biology and plant stress physiology. The researchers have options of choosing a par- ticular plant TF database for a single plant species. Alterna- tively one can choose a TF database, which can compare several TFs from various plant species side by side. All the databases will be enriched in future with completion of sev- eral other plant genome sequences. Plant TF databases are a vital part in studying the roles of TFs as well as aid in dis- covering new cell functions. The wide array TF databases freely available over the Internet are definitely a valuable resource for plant molecular biologists. It is important that the respective database developers update the databases fre- quently. 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