Bimodular auxin response controls organogenesis in Arabidopsis.
Like animals, the mature plant body develops via successive sets of instructions that determine cell fate, patterning, and organogenesis. In the coordination of various developmental programs, several plant hormones play decisive roles, among which auxin is the best-documented hormonal signal. Despite the broad range of processes influenced by auxin, how such a single signaling molecule can be translated into a multitude of distinct responses remains unclear. In Arabidopsis thaliana, lateral root development is a classic example of a developmental process that is controlled by auxin at multiple stages. Therefore, we used lateral root formation as a model system to gain insight into the multifunctionality of auxin. We were able to demonstrate the complementary and sequential action of two discrete auxin response modules, the previously described Solitary Root/indole-3-Acetic Acid (IAA)14-Auxin Response Factor (ARF)7-ARF19-dependent lateral root initiation module and the successive Bodenlos/IAA12-Monopteros/ARF5-dependent module, both of which are required for proper organogenesis. The genetic framework in which two successive auxin response modules control early steps of a developmental process adds an extra dimension to the complexity of auxin's action.
Department of Plant Systems Biology, Flanders Institute for Biotechnology, B-9052 Ghent, Belgium.
Ive
I
De Smet
Steffen
S
Lau
Ute
U
Voss
Steffen
S
Vanneste
René
R
Benjamins
Eike H
EH
Rademacher
Alexandra
A
Schlereth
Bert
B
De Rybel
Valya
V
Vassileva
Wim
W
Grunewald
Mirande
M
Naudts
Mitchell P
MP
Levesque
Jasmin S
JS
Ehrismann
Dirk
D
Inzé
Christian
C
Luschnig
Philip N
PN
Benfey
Dolf
D
Weijers
Marc C E
MC
Van Montagu
Malcolm J
MJ
Bennett
Gerd
G
Jürgens
Tom
T
Beeckman
D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics; D016213:Cyclins / Q000235:genetics; D050684:E2F Transcription Factors / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007210:Indoleacetic Acids / Q000494:pharmacology*; D009024:Morphogenesis; D010937:Plant Growth Regulators / Q000494:pharmacology; D018517:Plant Roots / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified; D017346:Protein Serine-Threonine Kinases; D011956:Receptors, Cell Surface / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
D029681:Arabidopsis Proteins; C496944:CycD3 protein, Arabidopsis; D016213:Cyclins; D050684:E2F Transcription Factors; C496141:E2Fa protein, Arabidopsis; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D011956:Receptors, Cell Surface; C462019:ACR4 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases