Regulatable endogenous production of cytokinins up to 'toxic' levels in transgenic plants and plant tissues.
The effects of expressing a chimeric gene consisting of a soybean heat shock gene promoter and a sequence that encodes an enzyme catalyzing the synthesis of a potent phytohormone, the cytokinin iPMP, have been analyzed in transgenic tobacco plants. The production of cytokinin endogenously produced several effects previously undocumented. The differentiation of shoots independent of exogenous cytokinin from heat-treated transgenic plant leaf explants demonstrates that long-term heat treatments do not interfere with complex developmental processes. This extends the potential usefulness of heat shock gene promoters to conditionally express genes during windows of development that span several weeks.
Botany Department, University of Georgia, Athens 30602.
W M
WM
Ainley
K J
KJ
McNeil
J W
JW
Hill
W L
WL
Lingle
R B
RB
Simpson
M L
ML
Brenner
R T
RT
Nagao
J L
JL
Key
D000241:Adenosine / Q000031:analogs & derivatives / Q000032:analysis; D019883:Alkyl and Aryl Transferases; D003583:Cytokinins / Q000096:biosynthesis* / Q000494:pharmacology; D004790:Enzyme Induction; D005786:Gene Expression Regulation; D017343:Genes, Plant / Q000235:genetics; D006360:Heat-Shock Proteins / Q000235:genetics; D006358:Hot Temperature; D007541:Isopentenyladenosine / Q000031:analogs & derivatives / Q000032:analysis; D009024:Morphogenesis / Q000187:drug effects; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D011401:Promoter Regions, Genetic / Q000235:genetics; D013025:Glycine max / Q000235:genetics*; D014026:Nicotiana / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D014166:Transferases / Q000235:genetics / Q000378:metabolism
D003583:Cytokinins; D006360:Heat-Shock Proteins; D007541:Isopentenyladenosine; C009699:zeatin riboside; D014166:Transferases; D019883:Alkyl and Aryl Transferases; C024274:adenylate isopentenyltransferase; D000241:Adenosine