Fig. 2From: An ancient retroviral RNA element hidden in mammalian genomes and its involvement in co-opted retroviral gene regulationSequence search for SPRE-like elements in ERV families. a Schematic representation of the two-step search for SPRE in the Dfam database. b Percentage of LTR-type retrotransposons (i.e., ERVs) among all repetitive DNA elements and ones with SPRE-like elements in the Dfam database. c A histogram of relative position scores of SPRE-like elements in Dfam families by the second-step search. The scores were calculated as [(S + E)/2]/L, where S and E are the start and end positions of the SPRE-like elements from the 5′ terminus, respectively, and L is the length of each Dfam family. Strandness was considered. d Sequence alignment and the sequence logo of 393 of SPRE-like elements. SPRE-core motif and C-rich motifs are indicatedBack to article page