Figure 2From: Putative cross-kingdom horizontal gene transfer in sponge (Porifera) mitochondriaPredicted secondary structure of the cox1 intron of Tetilla sp. The exon and intron sequences are in lower-case and in upper-case, respectively. The conserved sequences (P, Q, R, S) of the intron core and the base-paired regions P1–P9 are shown according to the standard scheme for group I introns [53].Back to article page