This study investigates the mechanisms underlying jasmonate-induced inhibition of primary root growth. Jasmonate inhibits the expression of two AP2-domain transcription factors, PLETHORA1 and 2, in a MYC2-dependent fashion. MYC2 is suggested to integrate the jasmonate and auxin pathways during the maintenance of the root stem cell niche. The root stem cell niche, which in the Arabidopsis thaliana root meristem is an area of four mitotically inactive quiescent cells (QCs) and the surrounding mitotically active stem cells, is critical for root development and growth. We report here that during jasmonate-induced inhibition of primary root growth, jasmonate reduces root meristem activity and leads to irregular QC division and columella stem cell differentiation. Consistently, jasmonate reduces the expression levels of the AP2-domain transcription factors PLETHORA1 (PLT1) and PLT2, which form a developmentally instructive protein gradient and mediate auxin-induced regulation of stem cell niche maintenance. Not surprisingly, the effects of jasmonate on root stem cell niche maintenance and PLT expression require the functioning of MYC2/JASMONATE INSENSITIVE1, a basic helix-loop-helix transcription factor that involves versatile aspects of jasmonate-regulated gene expression. Gel shift and chromatin immunoprecipitation experiments reveal that MYC2 directly binds the promoters of PLT1 and PLT2 and represses their expression. We propose that MYC2-mediated repression of PLT expression integrates jasmonate action into the auxin pathway in regulating root meristem activity and stem cell niche maintenance. This study illustrates a molecular framework for jasmonate-induced inhibition of root growth through interaction with the growth regulator auxin.
The Basic Helix-Loop-Helix Transcription Factor MYC2 Directly Represses PLETHORA Expression during Jasmonate-Mediated Modulation of the Root Stem Cell Niche in Arabidopsis[W][OA]
Qian Chen,Jiaqiang Sun,Qingzhe Zhai,Wenkun Zhou,Linlin Qi,Li Xu,Bao Wang,Rong Chen,Hongling Jiang,Jing Qi,Xugang Li,K. Palme,Chuanyou Li
Published 2011 in The Plant Cell
ABSTRACT
PUBLICATION RECORD
- Publication year
2011
- Venue
The Plant Cell
- Publication date
2011-09-01
- Fields of study
Biology, Medicine, Environmental Science
- Identifiers
- External record
- Source metadata
Semantic Scholar, PubMed
CITATION MAP
EXTRACTION MAP
CLAIMS
- No claims are published for this paper.
CONCEPTS
- No concepts are published for this paper.
REFERENCES
Showing 1-96 of 96 references · Page 1 of 1