@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} } @misc{BeninaRibeiroGechevetal.2015, author = {Benina, Maria and Ribeiro, Dimas Mendes and Gechev, Tsanko S. and M{\"u}ller-R{\"o}ber, Bernd and Schippers, Jos H. M.}, title = {A cell type-specific view on the translation of mRNAs from ROS-responsive genes upon paraquat treatment of Arabidopsis thaliana leaves}, series = {Plant, cell \& environment : cell physiology, whole-plant physiology, community physiology}, volume = {38}, journal = {Plant, cell \& environment : cell physiology, whole-plant physiology, community physiology}, number = {2}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0140-7791}, doi = {10.1111/pce.12355}, pages = {349 -- 363}, year = {2015}, abstract = {Oxidative stress causes dramatic changes in the expression levels of many genes. The formation of a functional protein through successful mRNA translation is central to a coordinated cellular response. To what extent the response towards reactive oxygen species (ROS) is regulated at the translational level is poorly understood. Here we analysed leaf- and tissue-specific translatomes using a set of transgenic Arabidopsis thaliana lines expressing a FLAG-tagged ribosomal protein to immunopurify polysome-bound mRNAs before and after oxidative stress. We determined transcript levels of 171 ROS-responsive genes upon paraquat treatment, which causes formation of superoxide radicals, at the whole-organ level. Furthermore, the translation of mRNAs was determined for five cell types: mesophyll, bundle sheath, phloem companion, epidermal and guard cells. Mesophyll and bundle sheath cells showed the strongest response to paraquat treatment. Interestingly, several ROS-responsive transcription factors displayed cell type-specific translation patterns, while others were translated in all cell types. In part, cell type-specific translation could be explained by the length of the 5-untranslated region (5-UTR) and the presence of upstream open reading frames (uORFs). Our analysis reveals insights into the translational regulation of ROS-responsive genes, which is important to understanding cell-specific responses and functions during oxidative stress. The study illustrates the response of different Arabidopsis thaliana leaf cells and tissues to oxidative stress at the translational level, an aspect of reactive oxygen species (ROS) biology that has been little studied in the past. Our data reveal insights into how translational regulation of ROS-responsive genes is fine-tuned at the cellular level, a phenomenon contributing to the integrated physiological response of leaves to stresses involving changes in ROS levels.}, language = {en} }