A genomic perspective on plant transcription factors

Data from the Arabidopsis genome project suggest that more than 5% of the g enes of this plant encode transcription factors. The necessity for the use of genomic analytical approaches becomes clear when it is considered that l ess than 10% of these factors have been genetically characterized. A variet y of tools for functional genomic analyses in plants have been developed ov er the past few years. The availability of the full complement of Arabidops is transcription factors, together with the results of recent studies that illustrate some of the challenges to their functional characterization, now provides the basic framework for future analyses of transcriptional regula tion in plants.