TY  - JOUR
A1  - Weiste, Christoph
A1  - Pedrotti, Lorenzo
A1  - Selvanayagam, Jebasingh
A1  - Muralidhara, Prathibha
A1  - Fröschel, Christian
A1  - Novák, Ondřej
A1  - Ljung, Karin
A1  - Hanson, Johannes
A1  - Dröge-Laser, Wolfgang
T1  - The Arabidopsis bZIP11 transcription factor links low-energy signalling to auxin-mediated control of primary root growth
JF  - PLoS Genetics
N2  - Plants have to tightly control their energy homeostasis to ensure survival and fitness under constantly changing environmental conditions. Thus, it is stringently required that energy-consuming stress-adaptation and growth-related processes are dynamically tuned according to the prevailing energy availability. The evolutionary conserved SUCROSE NON-FERMENTING1 RELATED KINASES1 (SnRK1) and the downstream group C/S\(_{1}\) basic leucine zipper (bZIP) transcription factors (TFs) are well-characterised central players in plants’ low-energy management. Nevertheless, mechanistic insights into plant growth control under energy deprived conditions remains largely elusive. In this work, we disclose the novel function of the low-energy activated group S\(_{1}\) bZIP11-related TFs as regulators of auxin-mediated primary root growth. Whereas transgenic gain-of-function approaches of these bZIPs interfere with the activity of the root apical meristem and result in root growth repression, root growth of loss-of-function plants show a pronounced insensitivity to low-energy conditions. Based on ensuing molecular and biochemical analyses, we propose a mechanistic model, in which bZIP11-related TFs gain control over the root meristem by directly activating IAA3/SHY2 transcription. IAA3/SHY2 is a pivotal negative regulator of root growth, which has been demonstrated to efficiently repress transcription of major auxin transport facilitators of the PIN-FORMED (PIN) gene family, thereby restricting polar auxin transport to the root tip and in consequence auxin-driven primary root growth. Taken together, our results disclose the central low-energy activated SnRK1-C/S\(_{1}\)-bZIP signalling module as gateway to integrate information on the plant’s energy status into root meristem control, thereby balancing plant growth and cellular energy resources.
KW  - root growth
KW  - sucrose
KW  - auxins
KW  - meristems
KW  - regulator genes
KW  - genetically modified plants
KW  - gene expression
KW  - plant growth and development
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-157742
VL  - 13
IS  - 2
ER  - 
TY  - JOUR
A1  - Walper, Elisabeth
A1  - Weiste, Christoph
A1  - Mueller, Martin J.
A1  - Hamberg, Mats
A1  - Dröge-Laser, Wolfgang
T1  - Screen Identifying Arabidopsis Transcription Factors Involved in the Response to 9-Lipoxygenase-Derived Oxylipins
JF  - PLoS One
N2  - 13-Lipoxygenase-derived oxylipins, such as jasmonates act as potent signaling molecules in plants. Although experimental evidence supports the impact of oxylipins generated by the 9-Lipoxygenase (9-LOX) pathway in root development and pathogen defense, their signaling function in plants remains largely elusive. Based on the root growth inhibiting properties of the 9-LOX-oxylipin 9-HOT (9-hydroxy-10,12,15-octadecatrienoic acid), we established a screening approach aiming at identifying transcription factors (TFs) involved in signaling and/or metabolism of this oxylipin. Making use of the AtTORF-Ex (Arabidopsis thaliana Transcription Factor Open Reading Frame Expression) collection of plant lines overexpressing TF genes, we screened for those TFs which restore root growth on 9-HOT. Out of 6,000 lines, eight TFs were recovered at least three times and were therefore selected for detailed analysis. Overexpression of the basic leucine Zipper (bZIP) TF TGA5 and its target, the monoxygenase CYP81D11 reduced the effect of added 9-HOT, presumably due to activation of a detoxification pathway. The highly related ETHYLENE RESPONSE FACTORs ERF106 and ERF107 induce a broad detoxification response towards 9-LOX-oxylipins and xenobiotic compounds. From a set of 18 related group S-bZIP factors isolated in the screen, bZIP11 is known to participate in auxin-mediated root growth and may connect oxylipins to root meristem function. The TF candidates isolated in this screen provide starting points for further attempts to dissect putative signaling pathways involving 9-LOX-derived oxylipins.
KW  - Jasmonic acid
KW  - root growth
KW  - arabidopsis thaliana
KW  - detoxification
KW  - seedlings
KW  - stress signaling cascade
KW  - hyperexpression techniques
KW  - ranscription factors
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146857
VL  - 11
IS  - 4
ER  -