SINE-promoted transcripts detected via 5′-capture. (A) Consensus sequence of all reads that match the reference B2 sequence and contain the TSO sequence. Green line indicates Pol III A box sequence. (B) Diagram of 5′- and 3′-end tagging to identify if TSO-bound B2 elements contain a Pol III termination sequence. (i) Total RNA is isolated from tissue; (ii) oligos are directly ligated onto the 3′-end of RNA; (iii) cDNA synthesis with template switching begins with a primer at the 3′-oligo and extends to attach the TSO sequence on the 5′-end. (iv) PCR with an oligo that spans the junction between the 5′-TSO sequence and the B2 promoter and a second primer that captures the 3′-end. (v) The whole PCR product is cloned for Sanger sequencing, with no size selection. (vi) Two examples of Sanger-sequenced clones with hallmarks of Pol III transcription. (Cf. Supplemental Data for sequences.)