Pheophytinase Knockdown Impacts Carbon Metabolism and Nutraceutical Content Under Normal Growth Conditions in Tomato
Although chlorophyll (Chl) degradation is an essential biochemical pathway for plant physiology, our knowledge regarding this process still has unfilled gaps. Pheophytinase (PPH) was shown to be essential for Chl breakdown in dark-induced senescent leaves. However, the catalyzing enzymes involved in pigment turnover and fruit ripening-associated degreening are still controversial. Chl metabolism is closely linked to the biosynthesis of other isoprenoid-derived compounds, such as carotenoids and tocopherols, which are also components of the photosynthetic machinery. Chls, carotenoids and tocopherols share a common precursor...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Lira, B. S., Rosado, D., Almeida, J., de Souza, A. P., Buckeridge, M. S., Purgatto, E., Guyer, L., Hörtensteiner, S., Freschi, L., Rossi, M. Tags: Regular Papers Source Type: research
Identification and Functional Characterization of Sesquiterpene Synthases from Xanthium strumarium
In this study, the cDNAs coding for three sesquiterpene synthases (designated as XsTPS1, XsTPS2 and XsTPS3) were isolated using the X. strumarium transcriptome that we recently constructed. XsTPS1, XsTPS2 and XsTPS3 were revealed to have primary activities forming germacrene D, guaia-4,6-diene and germacrene A, respectively, by either ectopic expression in yeast cells or purified recombinant protein-based in vitro assays. Quantitative real-time PCRs and metabolite analysis for the different plant parts showed that the transcript abundance of XsTPS1–XsTPS3 is consistent with the accumulation pattern of their enzymatic...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Li, Y., Chen, F., Li, Z., Li, C., Zhang, Y. Tags: Regular Papers Source Type: research
CsNIP2;1 is a Plasma Membrane Transporter from Cucumis sativus that Facilitates Urea Uptake When Expressed in Saccharomyces cerevisiae and Arabidopsis thaliana
Urea is an important source of nitrogen (N) for the growth and development of plants. It occurs naturally in soils, is the major N source in agricultural fertilizers and is an important N metabolite in plants. Therefore, the identification and characterization of urea transporters in higher plants is important for the fundamental understanding of urea-based N nutrition in plants and for designing novel strategies for improving the N-use efficiency of urea based-fertilizers. Progress in this area, however, is hampered due to scarce knowledge of plant urea transporters. From what is known, urea uptake from the soil into plan...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Zhang, L., Yan, J., Vatamaniuk, O. K., Du, X. Tags: Regular Papers Source Type: research
AtC3H17, a Non-Tandem CCCH Zinc Finger Protein, Functions as a Nuclear Transcriptional Activator and Has Pleiotropic Effects on Vegetative Development, Flowering and Seed Development in Arabidopsis
Despite increasing reports that CCCH zinc finger proteins function in plant development and stress responses, the functions and molecular aspects of many CCCH zinc finger proteins remain uncharacterized. Here, we characterized the biological and molecular functions of AtC3H17, a unique Arabidopsis gene encoding a non-tandem CCCH zinc finger protein. AtC3H17 was ubiquitously expressed throughout the life cycle of Arabidopsis plants and their organs. The rate and ratio of seed germination of atc3h17 mutants were slightly slower and lower, respectively, than those of the wild type (WT), whereas AtC3H17-overexpressing transgen...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Seok, H.-Y., Woo, D.-H., Park, H.-Y., Lee, S.-Y., Tran, H. T., Lee, E.-H., Vu Nguyen, L., Moon, Y.-H. Tags: Regular Papers Source Type: research
Branch Pathway Blocking in Artemisia annua is a Useful Method for Obtaining High Yield Artemisinin
There are many biosynthetic pathways competing for the metabolic flux with the artemisinin biosynthetic pathway in Artemisia annua L. To study the relationship between genes encoding enzymes at branching points and the artemisinin biosynthetic pathway, β-caryophyllene, β-farnesene and squalene were sprayed on young seedlings of A. annua. Transient expression assays indicated that the transcription levels of β-caryophyllene synthase (CPS), β-farnesene synthase (BFS) and squalene synthase (SQS) were inhibited by β-caryophyllene, β-farnesene and squalene, respectively, while expression of some ar...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Lv, Z., Zhang, F., Pan, Q., Fu, X., Jiang, W., Shen, Q., Yan, T., Shi, P., Lu, X., Sun, X., Tang, K. Tags: Regular Papers Source Type: research
The Petal-Specific InMYB1 Promoter Functions by Recognizing Petaloid Cells
The InMYB1 gene in Japanese morning glory (Ipomoea nil) is a member of the MYB transcription factor family. The promoter of InMYB1 has been reported to induce petal-specific gene expression in Arabidopsis and Eustoma, and has the same function in several other dicotyledonous plants. Most flowers consist of sepals, petals, stamens and a carpel, whose identity establishment is explained by the ABC model. The establishment of the identity of petals is determined by the expression of class A and B genes in whorl 2. The aim of this study was to clarify whether the InMYB1 promoter functions by recognizing whorl position or petal...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Azuma, M., Mitsuda, N., Goto, K., Oshima, Y., Ohme-Takagi, M., Otagaki, S., Matsumoto, S., Shiratake, K. Tags: Regular Papers Source Type: research
Exploiting the Substrate Promiscuity of Hydroxycinnamoyl-CoA:Shikimate Hydroxycinnamoyl Transferase to Reduce Lignin
In this study, we investigated the substrate promiscuity of HCT from a bryophyte (Physcomitrella) and from five representatives of vascular plants (Arabidopsis, poplar, switchgrass, pine and Selaginella) using a yeast expression system. We demonstrate for these HCTs a conserved capacity to acylate with p-coumaroyl-CoA several phenolic compounds in addition to the canonical acceptor shikimate normally used during lignin biosynthesis. Using either recombinant HCT from switchgrass (PvHCT2a) or an Arabidopsis stem protein extract, we show evidence of the inhibitory effect of these phenolics on the synthesis of p-coumaroyl shik...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Eudes, A., Pereira, J. H., Yogiswara, S., Wang, G., Teixeira Benites, V., Baidoo, E. E. K., Lee, T. S., Adams, P. D., Keasling, J. D., Loque, D. Tags: Regular Papers Source Type: research
Effects of Bleaching by Nitrogen Deficiency on the Quantum Yield of Photosystem II in Synechocystis sp. PCC 6803 Revealed by Chl Fluorescence Measurements
Estimation of photosynthesis by Chl fluorescence measurement of cyanobacteria is always problematic due to the interference from respiratory electron transfer and from phycocyanin fluorescence. The interference from respiratory electron transfer could be avoided by the use of DCMU or background illumination by blue light, which oxidizes the plastoquinone pool that tends to be reduced by respiration. On the other hand, the precise estimation of photosynthesis in cells with a different phycobilisome content by Chl fluorescence measurement is difficult. By subtracting the basal fluorescence due to the phycobilisome and PSI, i...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Ogawa, T., Sonoike, K. Tags: Regular Papers Source Type: research
The VviMYB80 Gene is Abnormally Expressed in Vitis vinifera L. cv. 'Zhong Shan Hong and its Expression in Tobacco Driven by the 35S Promoter Causes Male Sterility
In this study, we isolated and characterized cDNA for VviMYB80 expressed in flower buds of male-sterile Vitis vinifera L. cv. ‘Zhong Shan Hong’, a late-maturing cultivar derived from self-progeny of cv. ‘Wink’. VviMYB80 belongs to the MYB80 subfamily and clusters with AtMYB35/TDF1 in a distinct clade. We found that in flower buds, expression of the VviMYB80 gene in cv. ‘Zhong Shan Hong’ sharply increased at the tetrad stage, resulting in a higher and earlier transcript level than that found in cv. ‘Wink’. Expression of the VviMYB80 gene, driven by the 35S promoter, caused ple...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Zheng, H., Yu, X., Yuan, Y., Zhang, Y., Zhang, Z., Zhang, J., Zhang, M., Ji, C., Liu, Q., Tao, J. Tags: Regular Papers Source Type: research
The RING Finger E3 Ligase SpRing is a Positive Regulator of Salt Stress Signaling in Salt-Tolerant Wild Tomato Species
Protein ubiquitination in plants plays critical roles in many biological processes, including adaptation to abiotic stresses. Previously, RING finger E3 ligase has been characterized during salt stress response in several plant species, but little is known about its function in tomato. Here, we report that SpRing, a stress-inducible gene, is involved in salt stress signaling in wild tomato species Solanum pimpinellifolium ‘PI365967’. In vitro ubiquitination assay revealed that SpRing is an E3 ubiquitin ligase and the RING finger conserved region is required for its activity. SpRing is expressed in all tissues o...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Qi, S., Lin, Q., Zhu, H., Gao, F., Zhang, W., Hua, X. Tags: Regular Papers Source Type: research
Arabidopsis Mg-Protoporphyrin IX Methyltransferase Activity and Redox Regulation Depend on Conserved Cysteines
Redox regulation is an essential post-translational regulatory mechanism in prokaryotes and eukaryotes. The reversible oxidation and reduction of cysteine residues of proteins is also important in photosynthetic organisms to control enzymatic activities, protein stability and the interaction with other proteins of chloroplast-localized proteins. Several enzymes of the plant tetrapyrrole biosynthesis pathway have been identified to be redox regulated by thioredoxins (TRXs) and NADPH-dependent thioredoxin reductase C (NTRC). Among these proteins, Mg protoporphyrin IX methyltransferase (encoded by CHLM) was identified to be a...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Richter, A. S., Wang, P., Grimm, B. Tags: Regular Papers Source Type: research
Quantitative Proteomics-Based Reconstruction and Identification of Metabolic Pathways and Membrane Transport Proteins Related to Sugar Accumulation in Developing Fruits of Pear (Pyrus communis)
In conclusion, our data set comprehensively describes the proteome of developing pear fruits and provides novel insights about sugar accumulation as well as candidate genes for key reactions and transport steps. (Source: Plant and Cell Physiology)
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Reuscher, S., Fukao, Y., Morimoto, R., Otagaki, S., Oikawa, A., Isuzugawa, K., Shiratake, K. Tags: Regular Papers Source Type: research
Arabidopsis FH1 Formin Affects Cotyledon Pavement Cell Shape by Modulating Cytoskeleton Dynamics
Plant cell morphogenesis involves concerted rearrangements of microtubules and actin microfilaments. We previously reported that FH1, the main Arabidopsis thaliana housekeeping Class I membrane-anchored formin, contributes to actin dynamics and microtubule stability in rhizodermis cells. Here we examine the effects of mutations affecting FH1 (At3g25500) on cell morphogenesis and above-ground organ development in seedlings, as well as on cytoskeletal organization and dynamics, using a combination of confocal and variable angle epifluorescence microscopy with a pharmacological approach. Homozygous fh1 mutants exhibited cotyl...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Rosero, A., Oulehlova, D., Stillerova, L., Schiebertova, P., Grunt, M., Zarsky, V., Cvrckova, F. Tags: Regular Papers Source Type: research
Effects of Parental Temperature and Nitrate on Seed Performance are Reflected by Partly Overlapping Genetic and Metabolic Pathways
Seed performance is affected by the seed maturation environment, and previously we have shown that temperature, nitrate and light intensity were the most influential environmental factors affecting seed performance. Seeds developed in these environments were selected to assess the underlying metabolic pathways, using a combination of transcriptomics and metabolomics. These analyses revealed that the effects of the parental temperature and nitrate environments were reflected by partly overlapping genetic and metabolic networks, as indicated by similar changes in the expression levels of metabolites and transcripts. Nitrogen...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: He, H., Willems, L. A. J., Batushansky, A., Fait, A., Hanson, J., Nijveen, H., Hilhorst, H. W. M., Bentsink, L. Tags: Regular Papers Source Type: research
Three-Dimensional Imaging of Plant Organs Using a Simple and Rapid Transparency Technique
We describe a simple and rapid clearing and imaging method, termed ‘TOMEI’ (Transparent plant Organ MEthod for Imaging), which enables microscopic observation of intact plant organs. This method involves a clearing reagent containing 2,2'-thiodiethanol. Conveniently, transparent plant organs were prepared within only 3–6 h. We detected fluorescent stains at a depth of approximately 200 µm using confocal laser scanning microscopy and analyzed fluorescent proteins in internal tissues of transparent organs cleared using TOMEI. We adapted TOMEI for various plant organs of Arabidopsis thaliana and Oryza ...
Source: Plant and Cell Physiology - March 14, 2016 Category: Cytology Authors: Hasegawa, J., Sakamoto, Y., Nakagami, S., Aida, M., Sawa, S., Matsunaga, S. Tags: Rapid Paper Source Type: research
