Starting Ty element 16.4 Yeast Ty elements resemble retroviruses One delta unit is m arked Figure 16. 13 A unique Ty Base substitution element, engineered to contain an intron, transposes to give copies that lack the intron. The copies possess Promoter precedes element; intron is added identical terminal repeats Promoter Intron generated from one of the termini of the original Ty element Transposed elements have marked deltas and no intron 消当Figure 16.13 A unique Ty element, engineered to contain an intron, transposes to give copies that lack the intron. The copies possess identical terminal repeats, generated from one of the termini of the original Ty element. 16.4 Yeast Ty elements resemble retroviruses