Fig. 2

Little conservation of antisense transcripts across nematodes. Combinations of host genes and antisense transcripts from C. elegans were searched against 19 nematode genomes. If TBLASTN hits of the host gene span hits for the antisense transcripts on the opposite strand, a gene pair was marked as potentially conserved (dark blue). While spurious alignments and assembly problems can generate individual false negative and false positive calls, the overall distribution of candidates for conservation robustly indicates a strong lineage-specific signature, showing that even in the genus Caenorhabditis a large number of associations between host genes and antisense transcripts has either been lost or was specifically gained in the C. elegans lineage