bookmark QuadBase Allows multiplexed putative G4 (PG4) motif mining in large number of nucleotide sequences and also enables profiling complete prokaryotic genomes. QuadBase is linked with Ensembl's genomic datasets that allows virtually any organism's latest gene models or genomic assembly to be mined for the presence of PG4 motifs. The database also allows access to search in orthologues of eukaryotic genes through Ensembl's Compara. This web server provides intuitive graphical and sequence level representations of mined PG4 motifs and the results can be accessed later or be saved in convenient formats. The web server is designed, keeping in mind the requirements of both, the experimental and computational biologists, who want deep insights in to PG4 motif occurrences in their gene sets or genome of interest.