TY  - JOUR
A1  - Gliwicka, Marta
A1  - Balazadeh, Salma
A1  - Caldana, Camila
A1  - Müller-Röber, Bernd
A1  - Gaj, Malgorzata D.
T1  - The use of multi-qPCR platform and tan1 mutant in identification of TF genes involved in somatic embryogenesis in Arabidopsis
Y1  - 2009
UR  - http://www.ib.uj.edu.pl/abc/index.php?d=06
SN  - 0001-5296
ER  - 
TY  - JOUR
A1  - Balazadeh, Salma
A1  - Siddiqui, Hamad
A1  - Allu, Annapurna Devi
A1  - Matallana-Ramirez, Lilian Paola
A1  - Caldana, Camila
A1  - Mehrnia, Mohammad
A1  - Zanor, Maria-Inés
A1  - Koehler, Barbara
A1  - Müller-Röber, Bernd
T1  - A gene regulatory network controlled by the NAC transcription factor ANAC092/AtNAC2/ORE1 during salt-promoted senescence
N2  - P>The onset and progression of senescence are under genetic and environmental control. The Arabidopsis thaliana NAC transcription factor ANAC092 (also called AtNAC2 and ORE1) has recently been shown to control age-dependent senescence, but its mode of action has not been analysed yet. To explore the regulatory network administered by ANAC092 we performed microarray-based expression profiling using estradiol-inducible ANAC092 overexpression lines. Approximately 46% of the 170 genes up-regulated upon ANAC092 induction are known senescence-associated genes, suggesting that the NAC factor exerts its role in senescence through a regulatory network that includes many of the genes previously reported to be senescence regulated. We selected 39 candidate genes and confirmed their time-dependent response to enhanced ANAC092 expression by quantitative RT-PCR. We also found that the majority of them (24 genes) are up-regulated by salt stress, a major promoter of plant senescence, in a manner similar to that of ANAC092, which itself is salt responsive. Furthermore, 24 genes like ANAC092 turned out to be stage-dependently expressed during seed growth with low expression at early and elevated expression at late stages of seed development. Disruption of ANAC092 increased the rate of seed germination under saline conditions, whereas the opposite occurred in respective overexpression plants. We also detected a delay of salinity-induced chlorophyll loss in detached anac092-1 mutant leaves. Promoter-reporter (GUS) studies revealed transcriptional control of ANAC092 expression during leaf and flower ageing and in response to salt stress. We conclude that ANAC092 exerts its functions during senescence and seed germination through partly overlapping target gene sets.
Y1  - 2010
UR  - http://www3.interscience.wiley.com/cgi-bin/issn?DESCRIPTOR=PRINTISSN&VALUE=0960-7412
U6  - https://doi.org/10.1111/j.1365-313X.2010.04151.x
SN  - 0960-7412
ER  - 
TY  - JOUR
A1  - Balazadeh, Salma
A1  - Kwasniewski, Miroslaw
A1  - Caldana, Camila
A1  - Mehrnia, Mohammad
A1  - Zanor, Maria Ines
A1  - Xue, Gang-Ping
A1  - Müller-Röber, Bernd
T1  - ORS1, an H2O2-Responsive NAC Transcription Factor, Controls Senescence in Arabidopsis thaliana
JF  - Molecular plant
N2  - We report here that ORS1, a previously uncharacterized member of the NAC transcription factor family, controls leaf senescence in Arabidopsis thaliana. Overexpression of ORS1 accelerates senescence in transgenic plants, whereas its inhibition delays it. Genes acting downstream of ORS1 were identified by global expression analysis using transgenic plants producing dexamethasone-inducible ORS1-GR fusion protein. Of the 42 up-regulated genes, 30 (similar to 70%) were previously shown to be up-regulated during age-dependent senescence. We also observed that 32 (similar to 76%) of the ORS1-dependent genes were induced by long-term (4 d), but not short-term (6 h) salinity stress (150 mM NaCl). Furthermore, expression of 16 and 24 genes, respectively, was induced after 1 and 5 h of treatment with hydrogen peroxide (H2O2), a reactive oxygen species known to accumulate during salinity stress. ORS1 itself was found to be rapidly and strongly induced by H2O2 treatment in both leaves and roots. Using in vitro binding site selection, we determined the preferred binding motif of ORS1 and found it to be present in half of the ORS1-dependent genes. ORS1 is a paralog of ORE1/ANAC092/AtNAC2, a previously reported regulator of leaf senescence. Phylogenetic footprinting revealed evolutionary conservation of the ORS1 and ORE1 promoter sequences in different Brassicaceae species, indicating strong positive selection acting on both genes. We conclude that ORS1, similarly to ORE1, triggers expression of senescence-associated genes through a regulatory network that may involve cross-talk with salt- and H2O2-dependent signaling pathways.
KW  - NAC transcription factor
KW  - leaf senescence
KW  - gene expression
KW  - gene regulatory network
KW  - hydrogen peroxide
Y1  - 2011
U6  - https://doi.org/10.1093/mp/ssq080
SN  - 1674-2052
VL  - 4
IS  - 2
SP  - 346
EP  - 360
PB  - Oxford Univ. Press
CY  - Oxford
ER  -