TY  - JOUR
A1  - Devkar, Vikas
A1  - Thirumalaikumar, Venkatesh P.
A1  - Xue, Gang-Ping
A1  - Vallarino, Jose G.
A1  - Tureckova, Veronika
A1  - Strnad, Miroslav
A1  - Fernie, Alisdair R.
A1  - Hoefgen, Rainer
A1  - Mueller-Roeber, Bernd
A1  - Balazadeh, Salma
T1  - Multifaceted regulatory function of tomato SlTAF1 in the response to salinity stress
JF  - New phytologist : international journal of plant science
N2  - Salinity stress limits plant growth and has a major impact on agricultural productivity. Here, we identify NAC transcription factor SlTAF1 as a regulator of salt tolerance in cultivated tomato (Solanum lycopersicum).
While overexpression of SlTAF1 improves salinity tolerance compared with wild-type, lowering SlTAF1 expression causes stronger salinity-induced damage. Under salt stress, shoots of SlTAF1 knockdown plants accumulate more toxic Na+ ions, while SlTAF1 overexpressors accumulate less ions, in accordance with an altered expression of the Na+ transporter genes SlHKT1;1 and SlHKT1;2. Furthermore, stomatal conductance and pore area are increased in SlTAF1 knockdown plants during salinity stress, but decreased in SlTAF1 overexpressors.
We identified stress-related transcription factor, abscisic acid metabolism and defence-related genes as potential direct targets of SlTAF1, correlating it with reactive oxygen species scavenging capacity and changes in hormonal response. Salinity-induced changes in tricarboxylic acid cycle intermediates and amino acids are more pronounced in SlTAF1 knockdown than wild-type plants, but less so in SlTAF1 overexpressors. The osmoprotectant proline accumulates more in SlTAF1 overexpressors than knockdown plants.
In summary, SlTAF1 controls the tomato’s response to salinity stress by combating both osmotic stress and ion toxicity, highlighting this gene as a promising candidate for the future breeding of stress-tolerant crops.
KW  - abscisic acid (ABA)
KW  - ion homeostasis
KW  - NAC
KW  - proline
KW  - salt stress
KW  - SlTAF1
KW  - transcription factors
Y1  - 2019
U6  - https://doi.org/10.1111/nph.16247
SN  - 0028-646X
SN  - 1469-8137
VL  - 225
IS  - 4
SP  - 1681
EP  - 1698
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Ma, Xuemin
A1  - Balazadeh, Salma
A1  - Mueller-Roeber, Bernd
T1  - Tomato fruit ripening factor NOR controls leaf senescence
JF  - Journal of experimental botany
N2  - NAC transcription factors (TFs) are important regulators of expressional reprogramming during plant development, stress responses, and leaf senescence. NAC TFs also play important roles in fruit ripening. In tomato (Solanum lycopersicum), one of the best characterized NACs involved in fruit ripening is NON-RIPENING (NOR), and the non-ripening (nor) mutation has been widely used to extend fruit shelf life in elite varieties. Here, we show that NOR additionally controls leaf senescence. Expression of NOR increases with leaf age, and developmental as well as dark-induced senescence are delayed in the nor mutant, while overexpression of NOR promotes leaf senescence. Genes associated with chlorophyll degradation as well as senescence-associated genes (SAGs) show reduced and elevated expression, respectively, in nor mutants and NOR overexpressors. Overexpression of NOR also stimulates leaf senescence in Arabidopsis thaliana. In tomato, NOR supports senescence by directly and positively regulating the expression of several senescence-associated genes including, besides others, SlSAG15 and SlSAG113, SlSGR1, and SlYLS4. Finally, we find that another senescence control NAC TF, namely SlNAP2, acts upstream of NOR to regulate its expression. Our data support a model whereby NAC TFs have often been recruited by higher plants for both the control of leaf senescence and fruit ripening.
KW  - Aging
KW  - leaf
KW  - NAC
KW  - non-ripening
KW  - NOR
KW  - senescence
KW  - tomato
KW  - transcription factor
Y1  - 2019
U6  - https://doi.org/10.1093/jxb/erz098
SN  - 0022-0957
SN  - 1460-2431
VL  - 70
IS  - 10
SP  - 2727
EP  - 2740
PB  - Oxford Univ. Press
CY  - Oxford
ER  -