Fig. 5

In vitro self-splicing of Dsq.L2066 RNA. a The two main processing pathways, splicing and full-length intron circularization (FLC), and approach of RT-PCR/ Sanger sequencing assessments. The self-splicing pathway (left) involves two transesterification reactions. The first reaction (1.) is initiated by a nucleophilic attack by an exogenous guanosine cofactor (exoG). The second reaction (2.) starts with an attack at the 3′ splice site (3′SS) and results in ligated exons and excised linear intron. The FLC pathway (right) involves hydrolysis at the 3′SS (3.) followed by a nucleophilic attack (4.) at the 5′SS by the terminal guanosine (ωG). The FLC pathway is independent of exoG and results in full-length intron circles and fragmented exons. b Experiments of ligated exons (left) and full-length intron circle (right) junction analyses. RNA sequences corresponding to ligated exon junction and ligated FLC junction are presented below