Identification, and Functional and Expression Analyses of the CorA/MRS2/MGT-Type Magnesium Transporter Family in Maize
Magnesium (Mg2+) is an essential macronutrient for plant growth and development, and the CorA/MRS2/MGT-type Mg2+ transporters play important roles in maintaining Mg2+ homeostasis in plants. Although the MRS2/MGT genes have been identified in two model plant species, Arabidopsis and rice, a comprehensive analysis of the MRS2/MGT gene family in other plants is lacking. In this work, 12 putative MRS2/MGT genes (ZmMGT1– ZmMGT12) were identified in maize and all of them were classified into five distinct subfamilies by phylogenetic analysis. A complementation assay in the Salmonella typhimurium MM281 strain showed that fi...
Source: Plant and Cell Physiology - June 12, 2016 Category: Cytology Authors: Li, H., Du, H., Huang, K., Chen, X., Liu, T., Gao, S., Liu, H., Tang, Q., Rong, T., Zhang, S. Tags: Regular Papers Source Type: research
Arabidopsis MYB-Related HHO2 Exerts a Regulatory Influence on a Subset of Root Traits and Genes Governing Phosphate Homeostasis
Phosphate (Pi), an essential macronutrient required for growth and development of plants, is often limiting in soils. Pi deficiency modulates the expression of Pi starvation-responsive (PSR) genes including transcription factors (TFs). Here, we elucidated the role of the MYB-related TF HYPERSENSITIVITY TO LOW PHOSPHATE-ELICITED PRIMARY ROOT SHORTENING1 HOMOLOG2 (HHO2, At1g68670) in regulating Pi acquisition and signaling in Arabidopsis thaliana. HHO2 was specifically and significantly induced in different tissues in response to Pi deprivation. Transgenic seedlings expressing 35S::GFP::HHO2 confirmed the localization of HHO...
Source: Plant and Cell Physiology - June 12, 2016 Category: Cytology Authors: Nagarajan, V. K., Satheesh, V., Poling, M. D., Raghothama, K. G., Jain, A. Tags: Regular Papers Source Type: research
Synaptotagmin 1 Negatively Controls the Two Distinct Immune Secretory Pathways to Powdery Mildew Fungi in Arabidopsis
PEN1, one of the plasma membrane (PM) syntaxins, comprises an immune exocytic pathway by forming the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex with SNAP33 and VAMP721/722 in plants. Although this secretory pathway is also involved in plant growth and development, how plants control their exocytic activity is as yet poorly understood. Since constitutive PEN1 cycling between the PM and endocytosed vesicles is critical for its immune activity, we studied here the relationship of PEN1 to synaptotagmin 1 (SYT1) that is known to regulate endocytosis at the PM. Interestingly, syt1 plant...
Source: Plant and Cell Physiology - June 12, 2016 Category: Cytology Authors: Kim, H., Kwon, H., Kim, S., Kim, M. K., Botella, M. A., Yun, H. S., Kwon, C. Tags: Regular Papers Source Type: research
Efficient In Planta Detection and Dissection of De Novo Mutation Events in the Arabidopsis thaliana Disease Resistance Gene UNI
Plants possess disease resistance (R) proteins encoded by R genes, and each R protein recognizes a specific pathogen factor(s) for immunity. Interestingly, a remarkably high degree of polymorphisms in R genes, which are traces of past mutation events during evolution, suggest the rapid diversification of R genes. However, little is known about molecular aspects that facilitate the rapid change of R genes because of the lack of tools that enable us to monitor de novo R gene mutations efficiently in an experimentally feasible time scale, especially in living plants. Here we introduce a model assay system that enables efficie...
Source: Plant and Cell Physiology - June 12, 2016 Category: Cytology Authors: Ogawa, T., Mori, A., Igari, K., Morita, M. T., Tasaka, M., Uchida, N. Tags: Regular Papers Source Type: research
Close Relationships Between the PSII Repair Cycle and Thylakoid Membrane Dynamics
In chloroplasts, a three-dimensional network of thylakoid membranes is formed by stacked grana and interconnecting stroma thylakoids. The grana are crowded with photosynthetic proteins, where PSII–light harvesting complex II (LHCII) supercomplexes often show semi-crystalline arrays for efficient energy trapping, transfer and use. Although light is essential for photosynthesis, PSII is damaged by reactive oxygen species that are generated from primary photochemical reactions when plants are exposed to excess light. Because PSII complexes are embedded in the lipid bilayers of thylakoid membranes, their functions are af...
Source: Plant and Cell Physiology - June 12, 2016 Category: Cytology Authors: Yoshioka-Nishimura, M. Tags: Mini Review Source Type: research
The Stress-Induced Soybean NAC Transcription Factor GmNAC81 Plays a Positive Role in Developmentally Programmed Leaf Senescence
The onset of leaf senescence is a highly regulated developmental change that is controlled by both genetics and the environment. Senescence is triggered by massive transcriptional reprogramming, but functional information about its underlying regulatory mechanisms is limited. In the current investigation, we performed a functional analysis of the soybean (Glycine max) osmotic stress- and endoplasmic reticulum (ER) stress-induced NAC transcription factor GmNAC81 during natural leaf senescence using overexpression studies and reverse genetics. GmNAC81-overexpressing lines displayed accelerated flowering and leaf senescence b...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Pimenta, M. R., Silva, P. A., Mendes, G. C., Alves, J. R., Caetano, H. D. N., Machado, J. P. B., Brustolini, O. J. B., Carpinetti, P. A., Melo, B. P., Silva, J. C. F., Rosado, G. L., Ferreira, M. F. S., Dal-Bianco, M., Picoli, E. A. d. T., Aragao, F. J. L Tags: Regular Papers Source Type: research
Improvement of Arabidopsis Biomass and Cold, Drought and Salinity Stress Tolerance by Modified Circadian Clock-Associated PSEUDO-RESPONSE REGULATORs
In this study, we demonstrate that constitutive expression of engineered PRR5 (PRR5-VP), which functions as a transcriptional activator, can increase biomass and abiotic stress tolerance, similar to prr multiple mutants. Concomitant analyses of relative growth rate, flowering time and photosynthetic activity suggested that increased biomass of PRR5-VP plants is mostly due to late flowering, rather than to alterations in photosynthetic activity or growth rate. In addition, genome-wide gene expression profiling revealed that genes related to cold stress and water deprivation responses were up-regulated in PRR5-VP plants. PRR...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Nakamichi, N., Takao, S., Kudo, T., Kiba, T., Wang, Y., Kinoshita, T., Sakakibara, H. Tags: Regular Papers Source Type: research
Co-overexpressing a Plasma Membrane and a Vacuolar Membrane Sodium/Proton Antiporter Significantly Improves Salt Tolerance in Transgenic Arabidopsis Plants
The Arabidopsis gene AtNHX1 encodes a vacuolar membrane-bound sodium/proton (Na+/H+) antiporter that transports Na+ into the vacuole and exports H+ into the cytoplasm. The Arabidopsis gene SOS1 encodes a plasma membrane-bound Na+/H+ antiporter that exports Na+ to the extracellular space and imports H+ into the plant cell. Plants rely on these enzymes either to keep Na+ out of the cell or to sequester Na+ into vacuoles to avoid the toxic level of Na+ in the cytoplasm. Overexpression of AtNHX1 or SOS1 could improve salt tolerance in transgenic plants, but the improved salt tolerance is limited. NaCl at concentration >200 ...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Pehlivan, N., Sun, L., Jarrett, P., Yang, X., Mishra, N., Chen, L., Kadioglu, A., Shen, G., Zhang, H. Tags: Regular Papers Source Type: research
Precision Targeted Mutagenesis via Cas9 Paired Nickases in Rice
Recent reports of CRISPR- (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated protein 9) mediated heritable mutagenesis in plants highlight the need for accuracy of the mutagenesis directed by this system. Off-target mutations are an important issue when considering functional gene analysis, as well as the molecular breeding of crop plants with large genome size, i.e. with many duplicated genes, and where the whole-genome sequence is still lacking. In mammals, off-target mutations can be suppressed by using Cas9 paired nickases together with paired guide RNAs (gRNAs). However, the performanc...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Mikami, M., Toki, S., Endo, M. Tags: Regular Papers Source Type: research
In Vitro Assays of BciC Showing C132-Demethoxycarbonylase Activity Requisite for Biosynthesis of Chlorosomal Chlorophyll Pigments
In this study, we characterized the BciC derived from the green sulfur bacterium Chlorobaculum tepidum, and examined the in vitro enzymatic activities of its recombinant protein. The BciC-catalyzing reactions of various substrates showed that the enzyme recognized chlorophyllide (Chlide) a and 3,8-divinyl(DV)-Chlide a as chlorin substrates to give 3-vinyl-bacteriochlorophyllide (3V-BChlide) d and DV-BChlide d, respectively. Since the BciC afforded a higher activity with Chlide a than that with DV-Chlide a and no activity with (DV-)protoChlides a (porphyrin substrates) and 3V-BChlide a (a bacteriochlorin substrate), this en...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Teramura, M., Harada, J., Mizoguchi, T., Yamamoto, K., Tamiaki, H. Tags: Regular Papers Source Type: research
Involvement of EARLY BUD-BREAK, an AP2/ERF Transcription Factor Gene, in Bud Break in Japanese Pear (Pyrus pyrifolia Nakai) Lateral Flower Buds: Expression, Histone Modifications and Possible Target Genes
In the Japanese pear (Pyrus pyrifolia Nakai) ‘Kosui’, three developmental stages of lateral flower buds have been proposed to occur during ecodormancy to the flowering phase, i.e. rapid enlargement, sprouting and flowering. Here, we report an APETALA2/ethylene-responsive factor (AP2/ERF) transcription factor gene, named pear EARLY BUD-BREAK (PpEBB), which was highly expressed during the rapid enlargement stage occurring prior to the onset of bud break in flower buds. Gene expression analysis revealed that PpEBB expression was dramatically increased during the rapid enlargement stage in three successive growing ...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Anh Tuan, P., Bai, S., Saito, T., Imai, T., Ito, A., Moriguchi, T. Tags: Regular Papers Source Type: research
Oil Secretory System in Vegetative Organs of Three Arnica Taxa: Essential Oil Synthesis, Distribution and Accumulation
Arnica, a genus including the medicinal species A. montana, in its Arbo variety, and A. chamissonis, is among the plants richest in essential oils used as pharmaceutical materials. Despite its extensive use, the role of anatomy and histochemistry in the internal secretory system producing the essential oil is poorly understood. Anatomical sections allowed differentiation between two forms of secretory structures which differ according to their distribution in plants. The first axial type is connected to the vascular system of all vegetative organs and forms canals lined with epithelial cells. The second cortical type is re...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Kromer, K., Kreitschitz, A., Kleinteich, T., Gorb, S. N., Szumny, A. Tags: Regular Papers Source Type: research
A Novel Antifouling Defense Strategy from Red Seaweed: Exocytosis and Deposition of Fatty Acid Derivatives at the Cell Wall Surface
We investigated the organelles involved in the biosynthesis of fatty acid (FA) derivatives in the cortical cells of Laurencia translucida (Rhodophyta) and the effect of these compounds as antifouling (AF) agents. A bluish autofluorescence (with emission at 500 nm) within L. translucida cortical cells was observed above the thallus surface via laser scanning confocal microscopy (LSCM). A hexanic extract (HE) from L. translucida was split into two isolated fractions called hydrocarbon (HC) and lipid (LI), which were subjected to HPLC coupled to a fluorescence detector, and the same autofluorescence pattern as observed by LSC...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Paradas, W. C., Tavares Salgado, L., Pereira, R. C., Hellio, C., Atella, G. C., de Lima Moreira, D., do Carmo, A. P. B., Soares, A. R., Menezes Amado-Filho, G. Tags: Regular Papers Source Type: research
Oxidation of Cucurbitadienol Catalyzed by CYP87D18 in the Biosynthesis of Mogrosides from Siraitia grosvenorii
In this study, we report the successful identification of a multifunctional P450 (CYP87D18) as being involved in C-11 oxidation of cucurbitadienol. In vitro enzymatic activity assays showed that CYP87D18 catalyzed the oxidation of cucurbitadienol at C-11 to produce 11-oxo cucurbitadienol and 11-hydroxy cucurbitadienol. Furthermore, 11-oxo-24,25-epoxy cucurbitadienol as well as 11-oxo cucurbitadienol and 11-hydroxy cucurbitadienol were produced when CYP87D18 was co-expressed with SgCbQ in genetic yeast, and their structures were confirmed by liquid chromatography–solid-phase extraction–nuclear magnetic resonance...
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Zhang, J., Dai, L., Yang, J., Liu, C., Men, Y., Zeng, Y., Cai, Y., Zhu, Y., Sun, Y. Tags: Regular Papers Source Type: research
Chemical Promotion of Endogenous Amounts of ABA in Arabidopsis thaliana by a Natural Product, Theobroxide
In this report, it was found that a natural product, theobroxide, had potential as a plant chemical activator for stimulating the accumulation of ABA. Using theobroxide, the antagonistic effect of ABA against GAs was proved without exogenously applying ABA or using mutant plants. Our results suggest that ABA levels could be chemically controlled to elicit ABA-dependent biological phenomena. (Source: Plant and Cell Physiology)
Source: Plant and Cell Physiology - May 12, 2016 Category: Cytology Authors: Yamashita, Y., Ota, M., Inoue, Y., Hasebe, Y., Okamoto, M., Inukai, T., Masuta, C., Sakihama, Y., Hashidoko, Y., Kojima, M., Sakakibara, H., Inage, Y., Takahashi, K., Yoshihara, T., Matsuura, H. Tags: Regular Papers Source Type: research
