RRC ID 60681
Author Rast-Somssich MI, Žádníková P, Schmid S, Kieffer M, Kepinski S, Simon R.
Title The Arabidopsis JAGGED LATERAL ORGANS (JLO) gene sensitizes plants to auxin.
Journal J Exp Bot
Abstract Plant growth and development of new organs depend on the continuous activity of the meristems. In the shoot, patterns of organ initiation are determined by PINFORMED (PIN)-dependent auxin distribution, while the undifferentiated state of meristem cells requires activity of KNOTTED LIKE HOMEOBOX (KNOX) transcription factors. Cell proliferation and differentiation of the root meristem are regulated by the largely antagonistic functions of auxin and cytokinins. It has previously been shown that the transcription factor JAGGED LATERAL ORGANS (JLO), a member of the LATERAL ORGAN BOUNDARY DOMAIN (LBD) family, coordinates KNOX and PIN expression in the shoot and promotes root meristem growth. Here we show that JLO is required for the establishment of the root stem cell niche, where it interacts with the auxin/PLETHORA pathway. Auxin signaling involves the AUX/IAA co-repressor proteins, ARF transcription factors and F-box receptors of the TIR1/AFB1-5 family. Because jlo mutants fail to degrade the AUX/IAA protein BODENLOS, root meristem development is inhibited. We also demonstrate that the expression levels of two auxin receptors, TIR1 and AFB1, are controlled by JLO dosage, and that the shoot and root defects of jlo mutants are alleviated in jlo plants expressing TIR1 and AFB1 from a transgene. The finding that the auxin sensitivity of a plant can be differentially regulated through control of auxin receptor expression can explain how different developmental processes can be integrated by the activity of a key transcription factor.
Volume 68(11)
Pages 2741-2755
Published 2017-5-17
DOI 10.1093/jxb/erx131
PII 3784562
PMID 28472464
PMC PMC5853575
MeSH Arabidopsis / genetics* Arabidopsis / metabolism Arabidopsis Proteins / genetics* Arabidopsis Proteins / metabolism Arabidopsis Proteins / physiology F-Box Proteins / genetics F-Box Proteins / metabolism Gene Expression Regulation, Plant Genes, Plant Indoleacetic Acids / metabolism* Meristem / metabolism Plant Proteins / genetics Plant Proteins / metabolism Plant Roots / metabolism Receptors, Cell Surface / genetics Receptors, Cell Surface / metabolism Repressor Proteins / genetics* Repressor Proteins / physiology Signal Transduction
IF 5.36
Times Cited 4
Arabidopsis / Cultured plant cells, genes pst17018 pst19766 pst20504 pst00432 pst13957