THE PLANT CELL, Vol 1, Issue 2 217-227, Copyright © 1989 by American Society of Plant Biologists
Level of Expression of the Tomato rbcS-3A Gene is Modulated by a Far Upstream Promoter Element in a Developmentally Regulated Manner
T. Ueda, E. Pichersky, V. S. Malik and A. R. Cashmore
Plant Science Institute, Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6018
By Agrobacterium-mediated transformation we have demonstrated that a
1.10-kilobase promoter sequence from the tomato rbcS-3A gene confers
light-inducible and organ-specific expression upon fusion to the bacterial
chloramphenicol acetyltransferase gene. A biphasic expression profile was
obtained by 5[prime] deletion analysis of this promoter, indicating the
presence of both positive and negative regulatory elements. A severe
reduction in the level of expression was observed when the 5[prime]
-terminal 90 base pairs were deleted from the 1.10-kilobase promoter. DNA
sequence elements responsible for light inducibility and organ specificity
of the gene reside within the -374 base pairs of the proximal part of the
promoter and the sequences spanning from -374 to -205 are essential for
promoter function. The DNA sequences upstream from -374 modulate the level
of expression in leaf tissue; this modulation is under developmental
control.
