TY  - JOUR
AU  - Prerostova, Sylva
AU  - Dobrev, Petre I.
AU  - Gaudinova, Alena
AU  - Knirsch, Vojtech
AU  - Körber, Niklas
AU  - Pieruschka, Roland
AU  - Fiorani, Fabio
AU  - Brzobohatý, Břetislav
AU  - černý, Martin
AU  - Spichal, Lukas
AU  - Humplik, Jan
AU  - Vanek, Tomas
AU  - Schurr, Ulrich
AU  - Vankova, Radomira
TI  - Cytokinins: Their Impact on Molecular and Growth Responses to Drought Stress and Recovery in Arabidopsis
JO  - Frontiers in Functional Plant Ecology
VL  - 9
SN  - 1664-462X
CY  - Lausanne
PB  - Frontiers Media88991
M1  - FZJ-2018-03189
SP  - 655
PY  - 2018
AB  - Our phenotyping and hormonal study has characterized the role of cytokinins (CK) in the drought and recovery responses of Arabidopsis thaliana. CK down-regulation was achieved by overexpression of the gene for CK deactivating enzyme cytokinin oxidase/dehydrogenase (CKX): constitutive (35S:CKX) or at the stress onset using a dexamethasone-inducible pOp/LhGR promoter (DEX:CKX). The 35S:CKX plants exhibited slow ontogenesis and higher expression levels of stress-associated genes, e.g., AtP5CS1, already at well-watered conditions. CK down-regulation resulted during drought in higher stress tolerance (indicated by relatively low up-regulation of the expression of drought stress marker gene AtRD29B) accompanied with lower leaf water loss. Nevertheless, these plants exhibited slow and delayed recovery after re-watering. CK levels were increased at the stress onset by stimulation of the expression of CK biosynthetic gene isopentenyl transferase (ipt) (DEX:IPT) or by application of exogenous CK meta-topolin. After water withdrawal, long-term CK elevation resulted in higher water loss in comparison with CKX transformants as well as with plants overexpressing ipt driven by senescence-inducible SAG12 promoter (SAG:IPT), which gradually enhanced CKs during the stress progression. In all cases, CK up-regulation resulted in fast and more vigorous recovery. All drought-stressed plants exhibited growth suppression associated with elevation of abscisic acid and decrease of auxins and active CKs (with the exception of SAG:IPT plants). Apart from the ipt overexpressers, also increase of jasmonic and salicylic acid was found.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000432651900001
C6  - pmid:29872444
DO  - DOI:10.3389/fpls.2018.00655
UR  - https://juser.fz-juelich.de/record/846019
ER  -