Structural features of selected A. vaga Penelope retrotransposons. ORFs are represented by colored boxes with arrows. RT, reverse transcriptase; EN, endonuclease. Thin arrows denote pLTRs, and small colored rectangles - its optional short extension (“tail”). Panels (a-i) correspond to different families. Thicker arrows represent repeats derived from sequences other than pLTRs. N1 to N3 denote different N-rich inserts within ORFs, shown by darker colors. Palindromes are shown by double lines; frameshifts or stop codons, by vertical lines; deletions, by dashed lines; gaps, by dotted lines. Numbers above small yellow boxes indicate the length of target site duplications in bp. Scale bar, 1 kb.