@article{DongGuptaSieversetal.2019, author = {Dong, Yanni and Gupta, Saurabh and Sievers, Rixta and Wargent, Jason J. and Wheeler, David and Putterill, Joanna and Macknight, Richard and Gechev, Tsanko S. and M{\"u}ller-R{\"o}ber, Bernd and Dijkwel, Paul P.}, title = {Genome draft of the Arabidopsis relative Pachycladon cheesemanii reveals environment}, series = {BMC genomics}, volume = {20}, journal = {BMC genomics}, number = {1}, publisher = {BMC}, address = {London}, issn = {1471-2164}, doi = {10.1186/s12864-019-6084-4}, pages = {14}, year = {2019}, abstract = {BackgroundPachycladon cheesemanii is a close relative of Arabidopsis thaliana and is an allotetraploid perennial herb which is widespread in the South Island of New Zealand. It grows at altitudes of up to 1000m where it is subject to relatively high levels of ultraviolet (UV)-B radiation. To gain first insights into how Pachycladon copes with UV-B stress, we sequenced its genome and compared the UV-B tolerance of two Pachycladon accessions with those of two A. thaliana accessions from different altitudes.ResultsA high-quality draft genome of P. cheesemanii was assembled with a high percentage of conserved single-copy plant orthologs. Synteny analysis with genomes from other species of the Brassicaceae family found a close phylogenetic relationship of P. cheesemanii with Boechera stricta from Brassicaceae lineage I. While UV-B radiation caused a greater growth reduction in the A. thaliana accessions than in the P. cheesemanii accessions, growth was not reduced in one P. cheesemanii accession. The homologues of A. thaliana UV-B radiation response genes were duplicated in P. cheesemanii, and an expression analysis of those genes indicated that the tolerance mechanism in P. cheesemanii appears to differ from that in A. thaliana.ConclusionAlthough the P. cheesemanii genome shows close similarity with that of A. thaliana, it appears to have evolved novel strategies allowing the plant to tolerate relatively high UV-B radiation.}, language = {en} } @article{ThirumalaikumarDevkarMehterovetal.2017, author = {Thirumalaikumar, Venkatesh P. and Devkar, Vikas and Mehterov, Nikolay and Ali, Shawkat and Ozgur, Rengin and Turkan, Ismail and M{\"u}ller-R{\"o}ber, Bernd and Balazadeh, Salma}, title = {NAC transcription factor JUNGBRUNNEN1 enhances drought tolerance in tomato}, series = {Plant Biotechnology Journal}, volume = {16}, journal = {Plant Biotechnology Journal}, number = {2}, publisher = {Wiley}, address = {Hoboken}, issn = {1467-7644}, doi = {10.1111/pbi.12776}, pages = {354 -- 366}, year = {2017}, abstract = {Water deficit (drought stress) massively restricts plant growth and the yield of crops; reducing the deleterious effects of drought is therefore of high agricultural relevance. Drought triggers diverse cellular processes including the inhibition of photosynthesis, the accumulation of cell-damaging reactive oxygen species and gene expression reprogramming, besides others. Transcription factors (TF) are central regulators of transcriptional reprogramming and expression of many TF genes is affected by drought, including members of the NAC family. Here, we identify the NAC factor JUNGBRUNNEN1 (JUB1) as a regulator of drought tolerance in tomato (Solanum lycopersicum). Expression of tomato JUB1 (SlJUB1) is enhanced by various abiotic stresses, including drought. Inhibiting SlJUB1 by virus-induced gene silencing drastically lowers drought tolerance concomitant with an increase in ion leakage, an elevation of hydrogen peroxide (H2O2) levels and a decrease in the expression of various drought-responsive genes. In contrast, overexpression of AtJUB1 from Arabidopsis thaliana increases drought tolerance in tomato, alongside with a higher relative leaf water content during drought and reduced H2O2 levels. AtJUB1 was previously shown to stimulate expression of DREB2A, a TF involved in drought responses, and of the DELLA genes GAI and RGL1. We show here that SlJUB1 similarly controls the expression of the tomato orthologs SlDREB1, SlDREB2 and SlDELLA. Furthermore, AtJUB1 directly binds to the promoters of SlDREB1, SlDREB2 and SlDELLA in tomato. Our study highlights JUB1 as a transcriptional regulator of drought tolerance and suggests considerable conservation of the abiotic stress-related gene regulatory networks controlled by this NAC factor between Arabidopsis and tomato.}, language = {en} } @article{SakurabaBalazadehTanakaetal.2012, author = {Sakuraba, Yasuhito and Balazadeh, Salma and Tanaka, Ryouichi and M{\"u}ller-R{\"o}ber, Bernd and Tanaka, Ayumi}, title = {Overproduction of Chl b retards senescence through transcriptional reprogramming in arabidopsis}, series = {Plant \& cell physiology}, volume = {53}, journal = {Plant \& cell physiology}, number = {3}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0032-0781}, doi = {10.1093/pcp/pcs006}, pages = {505 -- 517}, year = {2012}, abstract = {Leaf senescence is a developmentally and environmentally regulated process which includes global changes in gene expression. Using Arabidopsis as a model, we modified Chl arrangement in photosystems by overexpressing the catalytic domain (the C domain) of chlorophyllide a oxygenase (CAO) fused with the linker domain (the B domain) of CAO and green fluorescent protein (GFP). In these plants (referred to as the BCG plants for the B and C domains of CAO and GFP), the Chl a/b ratio was drastically decreased and Chl b was incorporated into core antenna complexes. The BCG plants exhibited a significant delay of both developmental and dark-induced leaf senescence. The photosynthetic apparatus, CO2 fixation enzymes and the chloroplast structure were lost in wild-type plants during senescence, while BCG plants retained them longer than the wild type. Large-scale quantitative real-time PCR analyses of 1,880 transcription factor (TF) genes showed that 241 TFs are differentially expressed between BCG plants and wild-type plants at senescence, similar to 40\% of which are known senescence-associated genes (SAGs). Expression profiling also revealed the down-regulation of a large number of additional non-TF SAGs. In contrast, genes involved in photosynthesis were up-regulated, while those encoding Chl degradation enzymes were down-regulated in BCG plants. These results demonstrate that alteration of pigment composition in the photosynthetic apparatus retards senescence through transcriptional reprogramming.}, language = {en} } @article{BalazadehSchildhauerAraujoetal.2014, author = {Balazadeh, Salma and Schildhauer, Joerg and Araujo, Wagner L. and Munne-Bosch, Sergi and Fernie, Alisdair R. and Proost, Sebastian and Humbeck, Klaus and M{\"u}ller-R{\"o}ber, Bernd}, title = {Reversal of senescence by N resupply to N-starved Arabidopsis thaliana: transcriptomic and metabolomic consequences}, series = {Journal of experimental botany}, volume = {65}, journal = {Journal of experimental botany}, number = {14}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0022-0957}, doi = {10.1093/jxb/eru119}, pages = {3975 -- 3992}, year = {2014}, abstract = {Leaf senescence is a developmentally controlled process, which is additionally modulated by a number of adverse environmental conditions. Nitrogen shortage is a well-known trigger of precocious senescence in many plant species including crops, generally limiting biomass and seed yield. However, leaf senescence induced by nitrogen starvation may be reversed when nitrogen is resupplied at the onset of senescence. Here, the transcriptomic, hormonal, and global metabolic rearrangements occurring during nitrogen resupply-induced reversal of senescence in Arabidopsis thaliana were analysed. The changes induced by senescence were essentially in keeping with those previously described; however, these could, by and large, be reversed. The data thus indicate that plants undergoing senescence retain the capacity to sense and respond to the availability of nitrogen nutrition. The combined data are discussed in the context of the reversibility of the senescence programme and the evolutionary benefit afforded thereby. Future prospects for understanding and manipulating this process in both Arabidopsis and crop plants are postulated.}, language = {en} } @article{CzarnockaVanDerKelenWillemsetal.2017, author = {Czarnocka, Weronika and Van Der Kelen, Katrien and Willems, Patrick and Szechynska-Hebda, Magdalena and Shahnejat-Bushehri, Sara and Balazadeh, Salma and Rusaczonek, Anna and M{\"u}ller-R{\"o}ber, Bernd and Van Breusegem, Frank and Karpinski, Stanislaw}, title = {The dual role of LESION SIMULATING DISEASE 1 as a condition-dependent scaffold protein and transcription regulator}, series = {Plant, cell \& environment : cell physiology, whole-plant physiology, community physiology}, volume = {40}, journal = {Plant, cell \& environment : cell physiology, whole-plant physiology, community physiology}, publisher = {Wiley}, address = {Hoboken}, issn = {0140-7791}, doi = {10.1111/pce.12994}, pages = {2644 -- 2662}, year = {2017}, abstract = {Since its discovery over two decades ago as an important cell death regulator in Arabidopsis thaliana, the role of LESION SIMULATING DISEASE 1 (LSD1) has been studied intensively within both biotic and abiotic stress responses as well as with respect to plant fitness regulation. However, its molecular mode of action remains enigmatic. Here, we demonstrate that nucleo-cytoplasmic LSD1 interacts with a broad range of other proteins that are engaged in various molecular pathways such as ubiquitination, methylation, cell cycle control, gametogenesis, embryo development and cell wall formation. The interaction of LSD1 with these partners is dependent on redox status, as oxidative stress significantly changes the quantity and types of LSD1-formed complexes. Furthermore, we show that LSD1 regulates the number and size of leaf mesophyll cells and affects plant vegetative growth. Importantly, we also reveal that in addition to its function as a scaffold protein, LSD1 acts as a transcriptional regulator. Taken together, our results demonstrate that LSD1 plays a dual role within the cell by acting as a condition-dependent scaffold protein and as a transcription regulator.}, language = {en} }