Figure 8.

Model of antisense ERV retention in introns of cellular genes. Sense oriented ERV mRNA, shown by dashed lines, is transcribed from the LTR promoter (1). During transcription of the cellular gene, ERV mRNA anneals to the nascent cellular mRNA, shown as a solid line (2). During splicing, annealed ERV mRNA sterically hinders access to splice sites within the antisense ERV sequence, repressing exonization (3).