A screen for genes that function in abscisic acid signaling in Arabidopsis thaliana.
The plant hormone abscisic acid (ABA) controls many aspects of plant growth and development under a diverse range of environmental conditions. To identify genes functioning in ABA signaling, we have carried out a screen for mutants that takes advantage of the ability of wild-type Arabidopsis seeds to respond to (-)-(R)-ABA, an enantiomer of the natural (+)-(S)-ABA. The premise of the screen was to identify mutations that preferentially alter their germination response in the presence of one stereoisomer vs. the other. Twenty-six mutants were identified and genetic analysis on 23 lines defines two new loci, designated CHOTTO1 and CHOTTO2, and a collection of new mutant alleles of the ABA-insensitive genes, ABI3, ABI4, and ABI5. The abi5 alleles are less sensitive to (+)-ABA than to (-)-ABA. In contrast, the abi3 alleles exhibit a variety of differences in response to the ABA isomers. Genetic and molecular analysis of these alleles suggests that the ABI3 transcription factor may perceive multiple ABA signals.
Nambara
Eiji
E
Department of Botany, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2, Canada.
Suzuki
Masaharu
M
Abrams
Suzanne
S
McCarty
Donald R
DR
Kamiya
Yuji
Y
McCourt
Peter
P
D000040:Abscisic Acid / Q000737:chemistry / Q000494:pharmacology / Q000502:physiology*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D017343:Genes, Plant / Q000187:drug effects; D015398:Signal Transduction / Q000235:genetics*; D013237:Stereoisomerism; D014157:Transcription Factors / Q000378:metabolism
D014157:Transcription Factors; D000040:Abscisic Acid