Figure 3.

Schematic representation of structures of Penelope elements isolated from genomic libraries. (A) A Penelope-containing genomic clone of D. virilis. (B) A Penelope-containing genomic clone of D. lummei. Gray boxes indicate Penelope sequences; black boxes indicate sequences of the eyeless gene. The stippled box displays homologous regions of the eyeless gene in the two species. White (unshaded) boxes represent genomic sequences of unknown origin. The symbols X, N, E, B, and K represent the restriction sites XhoI, NdeI, EcoRI, BamHI, and KpnI, respectively. Asterisks indicate restriction sites that are damaged in D. lummei. Arrows above the boxes indicate the sizes and positions of fragments within a full-length Penelope element.