Figure 2

Structure of the captured retrotransposons associated with DSB repair.

De novo inserted retrotransposons at the Peg10-ORF2 (a–c), Cxx1a/b (d,e) and Rgag1 (f) loci were induced by pX330 injection into mouse zygotes. Both the post-integration site and pre-integration sequences (bottom of the panel) are shown. The nucleotide sequences that correspond to the single guide RNA sequence and the PAM sequences are shown in red and bold red characters, respectively. The black lines indicate the junction sites between pre- and post-integration sequences. The sequences in the blue boxes are overlapping microhomologies and are marked with black dotted lines. Short sequences of unknown origin are shown in green. Each insertion was truncated at both the 5′ and 3′ ends, but they demonstrated distinct features. These included the absence of LTRs and TSDs. (a) Together with MuERV-L, 50 bp of Peg10 cDNA sequence was inserted with 1-bp microhomology. (b) A truncated MaLR internal sequence was inserted with a 7-bp overlapping microhomology (a 2-bp mismatch). (c) A truncated MuERV-L Pol region was inserted with a 7-bp microhomology (1-bp mismatch) and 4-bp TSDs (yellow bars) ‘ttct’. (d) A truncated MuERV-L was inserted with 3-bp overlapping microhomology. (e) Multiple truncated retrotransposons were inserted with 1-5-bp microhomologies. (f) A truncated ORR1AI retrotransposon was inserted with a 6-bp microhomology (1-bp mismatch).