CREME: Cis-regulatory module explorer for the human genome

The binding of transcription factors to specific regulatory sequence elements is a primary mechanism for controlling gene transcription. Eukaryotic genes are often regulated by several transcription factors whose binding sites are tightly clustered and form cis-regulatory modules. In this paper, we present a web server, CREME, for identifying and visualizing cis-regulatory modules in the promoter regions of a given set of potentially co-regulated genes. CREME relies on a database of putative transcription factor binding sites that have been annotated across the human genome using a library of position weight matrices and evolutionary conservation with the mouse and rat genomes. A search algorithm is applied to this data set to identify combinations of transcription factors whose binding sites tend to co-occur in close proximity in the promoter regions of the input gene set. The identified cis-regulatory modules are statistically scored and significant combinations are reported and graphically visualized. Our web server is available at http://creme.dcode.org.