THE PLANT CELL, Vol 4, Issue 6 681-687, Copyright © 1992 by American Society of Plant Biologists
An Antisense Gene Stimulates Ethylene Hormone Production during Tomato Fruit Ripening
L. Penarrubia, M. Aguilar, L. Margossian and R. L. Fischer
Department of Plant Biology, University of California, Berkeley, California 94720
The ripening of many fruits is controlled by an increase in ethylene
hormone concentration. E8 is a fruit ripening protein that is related to
the enzyme that catalyzes the last step in the ethylene biosynthesis
pathway, 1-aminocyclopropane-1-carboxylic (ACC) oxidase. To determine the
function of E8, we have transformed tomato plants with an E8 antisense
gene. We show here that the antisense gene inhibits the accumulation of E8
protein during ripening. Whereas others have shown that reduction of ACC
oxidase results in reduced levels of ethylene biosynthesis, we find that
reduction of the related E8 protein produces the opposite effect, an
increase in ethylene evolution specifically during the ripening of detached
fruit. Thus, E8 has a negative effect on ethylene production in fruit.
