Figure 4.

Evidence for reconstitution of the 35S-mini-Tnt1 5' long terminal repeat (LTR), after transposition and for template switching between mini-Tnt1 and endogenous Tnt1 mRNA. (A) The alignment depicts the DNA sequence for the U3 region of the 5' LTR for three different Tnt1 elements. The top row is the sequence of a newly transposed, mini-35S-Tnt1 element. Full stops (periods) = identical residues; X = missing sequences; blue sequences = BI repeats; green sequences = BII repeats; red sequences = target site duplication; purple sequences = TATA box. The middle sequence is from the previously described d15ltr insertion [8], which shares sequence similarity to the newly transposed mini-Tnt1. The bottom sequence is from the progenitor mini-Tnt1. Note the absence of the 35 S promoter in the newly transposed 35S-mini-Tnt1. Note also the presence of an extra BII repeats in the newly transposed mini-Tnt1, which was probably acquired by template switching with mRNA from a native Tnt1 element.