A Feed-Forward Loop Consisting of the Response Regulator RpaB and the Small RNA PsrR1 Controls Light Acclimation of Photosystem I Gene Expression in the Cyanobacterium Synechocystis sp. PCC 6803
In this study, we found that the HLR1 DNA-binding motif, the recognition sequence for RpaB, is highly conserved in the core promoter region of the psrR1 gene among cyanobacterial species. Gel mobility shift assay revealed that RpaB binds to the HLR1 sequence of psrR1 in vitro. RNA gel blot analysis together with chromatin affinity purification (ChAP) analysis suggested that PSI genes are activated and the psrR1 gene is repressed by the binding of RpaB under low-light (LL) conditions. A decrease in DNA binding affinity of RpaB occurs within 5 min after the shift from LL to HL conditions, leading to the prompt decrease in PS...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Kadowaki, T., Nagayama, R., Georg, J., Nishiyama, Y., Wilde, A., Hess, W. R., Hihara, Y. Tags: Regular Papers Source Type: research
OsCOL10, a CONSTANS-Like Gene, Functions as a Flowering Time Repressor Downstream of Ghd7 in Rice
Flowering time, or heading date, is a critical agronomic trait that determines the cropping season and regional adaptability, and ultimately grain yield in rice. A number of genes involved in photoperiodic flowering have been cloned and their roles in modulating expression of the flowering genes have been characterized to a certain extent. However, much less is known about the pathway in transmitting the day length response signal(s) to induce transition to reproductive growth. Here, we report a constitutive flowering repressor OsCOL10, which encodes a member of the CONSTANS-like (COL) family. Transgenic rice plants overex...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Tan, J., Jin, M., Wang, J., Wu, F., Sheng, P., Cheng, Z., Wang, J., Zheng, X., Chen, L., Wang, M., Zhu, S., Guo, X., Zhang, X., Liu, X., Wang, C., Wang, H., Wu, C., Wan, J. Tags: Regular Papers Source Type: research
A Transcription Factor {gamma}MYB1 Binds to the P1BS cis-Element and Activates PLA2-{gamma} Expression with its Co-Activator {gamma}MYB2
In this study, analysis of the PLA2- promoter using a deletion series revealed that the promoter region –153 to –1 is crucial for its pollen specificity. Using a yeast one-hybrid screening assay with the PLA2- promoter and an Arabidopsis transcription factor (TF)-only library, we isolated two novel MYB-like TFs belonging to the MYB-CC family, denoted here as MYB1 and MYB2. By electrophoretic mobility shift assay, we found that these two TFs bind directly to the P1BS (phosphate starvation response 1-binding sequence) cis-element of the PLA2- promoter. MYB1 alone functioned as a transcriptional activator for PLA2...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Nguyen, H. T. K., Kim, S. Y., Cho, K.-M., Hong, J. C., Shin, J. S., Kim, H. J. Tags: Regular Papers Source Type: research
Ky-2, a Histone Deacetylase Inhibitor, Enhances High-Salinity Stress Tolerance in Arabidopsis thaliana
Adaptation to environmental stress requires genome-wide changes in gene expression. Histone modifications are involved in gene regulation, but the role of histone modifications under environmental stress is not well understood. To reveal the relationship between histone modification and environmental stress, we assessed the effects of inhibitors of histone modification enzymes during salinity stress. Treatment with Ky-2, a histone deacetylase inhibitor, enhanced high-salinity stress tolerance in Arabidopsis. We confirmed that Ky-2 possessed inhibition activity towards histone deacetylases by immunoblot analysis. To investi...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Sako, K., Kim, J.-M., Matsui, A., Nakamura, K., Tanaka, M., Kobayashi, M., Saito, K., Nishino, N., Kusano, M., Taji, T., Yoshida, M., Seki, M. Tags: Special Focus Issue - Regular Papers Source Type: research
Characterization of the Chloride Channel-Like, AtCLCg, Involved in Chloride Tolerance in Arabidopsis thaliana
In plant cells, anion channels and transporters are essential for key functions such as nutrition, ion homeostasis and resistance to biotic or abiotic stresses. We characterized AtCLCg, a member of the chloride channel (CLC) family in Arabidopsis localized in the vacuolar membrane. When grown on NaCl or KCl, atclcg knock-out mutants showed a decrease in biomass. In the presence of NaCl, these mutants overaccumulate chloride in shoots. No difference in growth was detected in response to osmotic stress by mannitol. These results suggest a physiological function of AtCLCg in the chloride homeostasis during NaCl stress. AtCLCg...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Nguyen, C. T., Agorio, A., Jossier, M., Depre, S., Thomine, S., Filleur, S. Tags: Special Focus Issue - Regular Papers Source Type: research
The Arabidopsis Mg Transporter, MRS2-4, is Essential for Mg Homeostasis Under Both Low and High Mg Conditions
Magnesium (Mg) is an essential macronutrient, functioning as both a cofactor of many enzymes and as a component of Chl. Mg is abundant in plants; however, further investigation of the Mg transporters involved in Mg uptake and distribution is needed. Here, we isolated an Arabidopsis thaliana mutant sensitive to high calcium (Ca) conditions without Mg supplementation. The causal gene of the mutant encodes MRS2-4, an Mg transporter. MRS2-4 single mutants exhibited growth defects under low Mg conditions, whereas an MRS2-4 and MRS2-7 double mutant exhibited growth defects even under normal Mg concentrations. Under normal Mg con...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Oda, K., Kamiya, T., Shikanai, Y., Shigenobu, S., Yamaguchi, K., Fujiwara, T. Tags: Special Focus Issue - Regular Papers Source Type: research
Visualization of Uptake of Mineral Elements and the Dynamics of Photosynthates in Arabidopsis by a Newly Developed Real-Time Radioisotope Imaging System (RRIS)
Minerals and photosynthates are essential for many plant processes, but their imaging in live plants is difficult. We have developed a method for their live imaging in Arabidopsis using a real-time radioisotope imaging system. When each radioisotope, 22Na, 28Mg, 32P-phosphate, 35S-sulfate, 42K, 45Ca, 54Mn and 137Cs, was employed as an ion tracer, ion movement from root to shoot over 24 h was clearly observed. The movements of 22Na, 42K, 32P, 35S and 137Cs were fast so that they spread to the tip of stems. In contrast, high accumulation of 28Mg, 45Ca and 54Mn was found in the basal part of the main stem. Based on this time-...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Sugita, R., Kobayashi, N. I., Hirose, A., Saito, T., Iwata, R., Tanoi, K., Nakanishi, T. M. Tags: Special Focus Issue - Regular Papers Source Type: research
Dual regulation of root hydraulic conductivity and plasma membrane aquaporins by plant nitrate accumulation and high-affinity nitrate transporter NRT2.1
In conclusion, this work reveals that control of Arabidopsis Lpr and PIP functions by NO3– involves novel shoot to root signaling and NRT2.1-dependent functions. (Source: Plant and Cell Physiology)
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Li, G., Tillard, P., Gojon, A., Maurel, C. Tags: Special Focus Issue - Regular Papers Source Type: research
Highly Sprouting-Tolerant Wheat Grain Exhibits Extreme Dormancy and Cold Imbibition-Resistant Accumulation of Abscisic Acid
In this study, we used PHS-tolerant varieties, Gifu-komugi (Gifu) and OS38, to characterize the mechanisms of both dormancy breakage and dormancy maintenance at low temperatures. Physiologically mature Gifu grains exhibited dormancy after imbibition at 20°C, but germinated at 15°C. In contrast, OS38 grains remained dormant even at temperatures as low as 5°C. Embryo half-grains cut out from the dormant Gifu grains germinated by imbibition at 20°C, similar to conventional varieties worldwide. However, OS38 embryo half-grains were still dormant. Hormonome and pharmacological analyses suggested that ABA and gib...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Kashiwakura, Y.-i., Kobayashi, D., Jikumaru, Y., Takebayashi, Y., Nambara, E., Seo, M., Kamiya, Y., Kushiro, T., Kawakami, N. Tags: Special Focus Issue - Regular Papers Source Type: research
Plant Nitrogen Acquisition Under Low Availability: Regulation of Uptake and Root Architecture
Nitrogen availability is a major factor determining plant growth and productivity. Plants acquire nitrogen nutrients from the soil through their roots mostly in the form of ammonium and nitrate. Since these nutrients are scarce in natural soils, plants have evolved adaptive responses to cope with the environment. One of the most important responses is the regulation of nitrogen acquisition efficiency. This review provides an update on the molecular determinants of two major drivers of the nitrogen acquisition efficiency: (i) uptake activity (e.g. high-affinity nitrogen transporters) and (ii) root architecture (e.g. low-nit...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Kiba, T., Krapp, A. Tags: Special Focus Issue - Mini Review Source Type: research
Performance and Limitations of Phosphate Quantification: Guidelines for Plant Biologists
Phosphate (Pi) is a macronutrient that is essential for plant life. Several regulatory components involved in Pi homeostasis have been identified, revealing a very high complexity at the cellular and subcellular levels. Determining the Pi content in plants is crucial to understanding this regulation, and short real-time 33Pi uptake imaging experiments have shown Pi movement to be highly dynamic. Furthermore, gene modulation by Pi is finely controlled by localization of this ion at the tissue as well as the cellular and subcellular levels. Deciphering these regulations requires access to and quantification of the Pi pool in...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Kanno, S., Cuyas, L., Javot, H., Bligny, R., Gout, E., Dartevelle, T., Hanchi, M., Nakanishi, T. M., Thibaud, M.-C., Nussaume, L. Tags: Special Focus Issue - Reviews Source Type: research
Asparagine Metabolic Pathways in Arabidopsis
Inorganic nitrogen in the form of ammonium is assimilated into asparagine via multiple steps involving glutamine synthetase (GS), glutamate synthase (GOGAT), aspartate aminotransferase (AspAT) and asparagine synthetase (AS) in Arabidopsis. The asparagine amide group is liberated by the reaction catalyzed by asparaginase (ASPG) and also the amino group of asparagine is released by asparagine aminotransferase (AsnAT) for use in the biosynthesis of amino acids. Asparagine plays a primary role in nitrogen recycling, storage and transport in developing and germinating seeds, as well as in vegetative and senescence organs. A sma...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Gaufichon, L., Rothstein, S. J., Suzuki, A. Tags: Special Focus Issue - Reviews Source Type: research
Staying Alive: Molecular Aspects of Seed Longevity
Mature seeds are an ultimate physiological status that enables plants to endure extreme conditions such as high and low temperature, freezing and desiccation. Seed longevity, the period over which seed remains viable, is an important trait not only for plant adaptation to changing environments, but also, for example, for agriculture and conservation of biodiversity. Reduction of seed longevity is often associated with oxidation of cellular macromolecules such as nucleic acids, proteins and lipids. Seeds possess two main strategies to combat these stressful conditions: protection and repair. The protective mechanism include...
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Sano, N., Rajjou, L., North, H. M., Debeaujon, I., Marion-Poll, A., Seo, M. Tags: Special Focus Issue - Reviews Source Type: research
Special Focus Issue on Plant Responses to the Environment
(Source: Plant and Cell Physiology)
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Ingram, G. C., Fujiwara, T. Tags: Editorials Source Type: research
A Word from the New Editor-In-Chief
(Source: Plant and Cell Physiology)
Source: Plant and Cell Physiology - April 18, 2016 Category: Cytology Authors: Sakakibara, H. Tags: Editorials Source Type: research
