Overview of the workflow leading to CEXlists. A) The atomic motifs are extracted from the cisRED database for gene pairs associating the gene of interest g and the 18.000 other genes described in the database. B) The number of SSMs is computed for all the studied SSM types (L) and all the gene pairs. C) The numbers of SSMs are corrected by the amount of potential SSMs (SSMC) and the p-value testing the null hypothesis: "the SSMC value is not greater than expected by chance" is computed. D) The lowest p-value obtained for each gene pair is used as the cp-value. The CEXlist(g, L, t) retains the genes for which a cp-value below a threshold t is computed when paired with g.