Figure 1.

(A) A single En-1 element cosegregates with pooled sur2/+ F₂ plants and is absent from +/+ F₂s. The DNA from five pooled +/+ F₂ lines and from two sets of five pooled F₂ sur2/+ lines (sets 1 and 2) was Southern blotted and probed with the 3′ end of the En-1 element. A single hybridizing band of 5 kb is indicated with an arrow; this is present in both sur2/+ pooled samples but is absent from the +/+ sample. (B) An En-1 insertion disrupts the cyt P450 gene CYP83B1. DNA was Southern blotted and probed with the 5′ end of CYP83B1. Arrows indicate the bands migrating at 5.0 kb and 2.6 kb, which result from disruption of the cyt P450 gene.