THE PLANT CELL, Vol 2, Issue 8 723-730, Copyright © 1990 by American Society of Plant Biologists
Rapid Proliferation of the Maize Transposable Element Activator in Transgenic Tomato
J. I. Yoder
Department of Vegetable Crops, University of California-Davis, Davis, California 95616
We have found that the maize transposable element Activator (Ac) can
rapidly proliferate when transformed into tomato plants. The fate of
transposed Ac elements in self-pollinated progeny of independent transgenic
tomato plants was examined by DNA gel blot hybridizations. When a single
copy of Ac was introduced into a transformant, the number of copies usually
remained low in subsequent generations. In one lineage, however, the number
of Ac elements increased from one to more than 15 copies in only two
generations. DNA gel blot analyses indicated that the amplified elements
were not grossly rearranged. Amplified copies of Ac resided at unique sites
in the genome, and segregation analysis indicated that these sites were not
tightly linked at one genetic locus. Taken together, these observations
indicate that the mechanism of Ac amplification is associated with
transposition.
