## 2 Results
The correlation between genome coverages of major TE classes (SINE, LINE, LTR, DNA, and rolling circle) and genome sizes; (**B**) median length of intron; (**C**) Adjusted by Pearson correlation \(p\)-values (P) and coefficients (R2); (**D**) Repeat landscape of the major classes of TE classes (SINE, LINE, LTR, DNA, and rolling circle) in the analyzed genomes. The Kimura substitution levels (\(x\)-axis) show sequence divergence, or “TE age”, for the major classes. The classes that are skewed to the left (less sequence divergence) are estimated to have more recently diversified histories than the classes that are skewed to the right. We next studied associations among intron length, genome size, and repeat content in Orthoptera, including _A. domesticus_, because they have been reported to be mutually correlated [55]. Median length of the _A. domesticus_ gene model was 602 bp, which was about one-tenth of that of _L. migratoria_ (Table 2). We found that total contents of repetitive elements and median length of introns in orthopteran species, including locust, were positively correlated (_p_ = 0.044 and R2 = 0.51), but not within the cricket species (_p_ = 0.791 and R2 < 0.01) (Figure 56b). Further, correlations between intron length and major TE contents were positive for LINE, LTR elements and DNA transposon in Orthoptera (LINE, \(p\) < 0.001 and R2 = 0.70; LTR, \(p\) < 0.001 and R2 = 0.49; DNA, \(p\) < 0.001 and R2 = 0.89) (Figure 4C), but not for SINE and rolling circle. These correlations were no longer established except for DNA transposons after limiting the analysis to crickets only (DNA, \(p\) = 0.034 and R2 = 0.05) (Figure 56b). There also was significant and strong positive correlation between the median length of introns and genome size in orthopteran species (_p_ < 0.001 and R2 = 0.97) (Figure 56c). However, when limited to the analysis within crickets, genome size did not correlate with intron length (_p_ = 0.949 and R2 < 0.01). Furthermore, a more detailed examination of the classes of TEs in Orthoptera revealed a positive correlation with intron length and genome size for LINE/CR1, LINE/L1, LINE/Penelope, LINE/RTE, DNA/hAT, DNA/Kolobok, and DNA/TcMar (Table S7). These results suggest that repetitive elements, especially several classes of TEs, such as LINE and DNA transposon, may contribute to variation in genome size and intron length in Orthoptera, and that while they are unlikely to be highly correlated within closely related species belonging to the same family, they are more likely highly correlated at the suborder level. We also examined whether abundance pattern of TEs in orthopteran genomes is due to shared ancient proliferation events or recent/ongoing activity of TE. We analyzed the distribution of sequence divergence of the annotated TE to infer the timing of the change in TE composition. As a result, we found TE distribution patterns that were _A. domesticus_-specific or common to crickets (Figure 4D). In _A. domesticus_, distributions of LTR transposon, especially LTR/ERV1 and LTR/Gypsy, showed a high abundance of recently diverged TE sequences compared to the other species, indicating an ongoing proliferative activity (Figure 56d-f). Likewise, a similar pattern was seen in SINE of the _T. occipitalis_ genome. On the other hand, the distribution pattern of DNA transposons in the orthopteran genomes examined here is relatively similar among the crickets, suggesting a possible shared activity of DNA transposons in ancient lineages of the crickets. Regarding the promoters and genes annotated for genetic engineering, for genetic engineering experiments, we identified promoters of specific genes of interest (GOI). First, we identified and annotated the vermition gene from _A. domesticus_ (Ad vermition) (Figure 5a) as our target for CRISPR editing and the muscle actin gene from _A. domesticus_ (Ad muscle actin) (Figure 5b) for a promoter for GOI expression. The Ad vermition mRNA was identified from our previously published _A. domesticus_ transcriptome data [22] by tBlastn using the _T.