TY  - JOUR
AB  - Plants are constantly exposed to stressful environmental conditions. Plant stress reactions were mainly investigated for single stress factors. However, under natural conditions plants may be simultaneously exposed to different stresses. Responses to combined stresses cannot be predicted from the reactions to the single stresses. Flavonoids accumulate in Arabidopsis thaliana during exposure to UV-A, UV-B, or cold, but the interactions of these factors on flavonoid biosynthesis were unknown. We therefore investigated the interaction of UV radiation and cold in regulating the expression of well-characterized stress-regulated genes, and on transcripts and metabolites of the flavonoid biosynthetic pathway in 52 natural Arabidopsis accessions that differ widely in their freezing tolerance. The data revealed interactions of cold and UV on the regulation of stress-related and flavonoid biosynthesis genes, and on flavonoid composition. In many cases, plant reactions to a combination of cold and UV were unique under combined stress and not predictable from the responses to the single stresses. Strikingly, all correlations between expression levels of flavonoid biosynthesis genes and flavonol levels were abolished by UV-B exposure. Similarly, correlations between transcript levels of flavonoid biosynthesis genes or flavonoid contents, and freezing tolerance were lost in the presence of UV radiation, while correlations with the expression levels of cold regulated genes largely persisted. This may indicate different molecular cold acclimation responses in the presence or absence of UV radiation.
AU  - Schulz, E.*
AU  - Tohge, T.*
AU  - Winkler, J.B.
AU  - Albert, A.
AU  - Schäffner, A.
AU  - Fernie, A.R.*
AU  - Zuther, E.*
AU  - Hincha, D.K.*
C1  - 61346
C2  - 50175
CY  - Great Clarendon St, Oxford Ox2 6dp, England
SP  - 502-514
TI  - Natural variation among Arabidopsis accessions in the regulation of flavonoid metabolism and stress gene expression by combined UV radiation and cold.
JO  - Plant Cell Physiol.
VL  - 62
IS  - 3
PB  - Oxford Univ Press
PY  - 2021
SN  - 0032-0781
ER  - 

TY  - JOUR
AB  - Bread wheat is a major crop that has long been the focus of basic and breeding research. Assembly of its genome has been difficult because of its large size and allohexaploid nature (AABBDD genome). Following the first reported assembly of the genome of the experimental strain Chinese Spring (CS), the 10+ Wheat Genomes Project was launched to produce multiple assemblies of worldwide modern cultivars. The only Asian cultivar in the project is Norin 61, a representative Japanese cultivar adapted to grow across a broad latitudinal range, mostly characterized by a wet climate and a short growing season. Here, we characterize key aspects of its chromosome-scale genome assembly spanning 15 Gb with a raw scaffold N50 of 23 Mb. Analysis of the repetitive elements identified chromosomal regions unique to Norin 61 that encompass a tandem array of the pathogenesis-related-13 family. We report novel copy-number variations in the B homeolog of the florigen gene FT1/VRN3, pseudogenization of its D homeolog, and the association of its A homeologous alleles with the spring/winter growth habit. Further, the Norin 61 genome carries typical East Asian functional variants from CS ranging from a single nucleotide to multi-Mb scale. Examples of such variation are the Fhb1 locus, which confers Fusarium head-blight resistance, Ppd-D1a, which confers early flowering, Glu-D1f for Asian noodle quality, and Rht-D1b, which introduced semi-dwarfism during the green revolution. The adoption of Norin 61 as a reference assembly for functional and evolutionary studies will enable comprehensive characterization of the underexploited Asian bread wheat diversity.
AU  - Shimizu, K.K.*
AU  - Copetti, D.*
AU  - Okada, M.*
AU  - Wicker, T.*
AU  - Tameshige, T.*
AU  - Hatakeyama, M.*
AU  - Shimizu-Inatsugi, R.*
AU  - Aquino, C.*
AU  - Nishimura, K.*
AU  - Kobayashi, F.*
AU  - Murata, K.*
AU  - Kuo, T.*
AU  - Delorean, E.*
AU  - Poland, J.*
AU  - Haberer, G.
AU  - Spannagl, M.
AU  - Mayer, K.F.X.
AU  - Gutierrez-Gonzalez, J.*
AU  - Muehlbauer, G.J.*
AU  - Monat, C.*
AU  - Himmelbach, A.*
AU  - Padmarasu, S.*
AU  - Mascher, M.*
AU  - Walkowiak, S.*
AU  - Nakazaki, T.*
AU  - Ban, T.*
AU  - Kawaura, K.*
AU  - Tsuji, H.*
AU  - Pozniak, C.*
AU  - Stein, N.*
AU  - Sese, J.*
AU  - Nasuda, S.*
AU  - Handa, H.*
C1  - 60635
C2  - 49511
CY  - Great Clarendon St, Oxford Ox2 6dp, England
SP  - 8-27
TI  - De novo genome assembly of the Japanese wheat cultivar norin 61 highlights functional variation in flowering time and fusarium resistance genes in East Asian genotypes.
JO  - Plant Cell Physiol.
VL  - 62
IS  - 1
PB  - Oxford Univ Press
PY  - 2021
SN  - 0032-0781
ER  - 

TY  - JOUR
AB  - Accumulation of heavy metals such as zinc (Zn) disturbs the metabolism of reactive oxygen (e.g. hydrogen peroxide, H2O2) and nitrogen species (e.g. nitric oxide, NO; S-nitrosoglutathione, GSNO) in plant cells; however, their signal interactions are not well understood. Therefore, this study examines the interplay between H2O2 metabolism and GSNO signaling in Arabidopsis. Comparing the Zn tolerance of the wild type (WT), GSNO reductase (GSNOR) overexpressor 35S::FLAG-GSNOR1 and GSNOR-deficient gsnor1-3, we observed relative Zn tolerance of gsnor1-3, which was not accompanied by altered Zn accumulation capacity. Moreover, in gsnor1-3 plants Zn did not induce NO/S-nitrosothiol (SNO) signaling, possibly due to the enhanced activity of NADPH-dependent thioredoxin reductase. In WT and 35S::FLAG-GSNOR1, GSNOR was inactivated by Zn, and Zn-induced H2O2 is directly involved in the GSNOR activity loss. In WT seedlings, Zn resulted in a slight intensification of protein nitration detected by Western blot and protein S-nitrosation observed by resin-assisted capture of SNO proteins (RSNO-RAC). LC-MS/MS analyses indicate that Zn induces the S-nitrosation of ascorbate peroxidase 1. Our data collectively show that Zn-induced H2O2 may influence its own level, which involves GSNOR inactivation-triggered SNO signaling. These data provide new evidence for the interplay between H2O2 and SNO signaling in Arabidopsis plants affected by metal stress.
AU  - Kolbert, Z.*
AU  - Molnar, A.*
AU  - Oláh, D.*
AU  - Feigl, G.*
AU  - Horváth, E.*
AU  - Erdei, L.*
AU  - Ördög, A.*
AU  - Rudolf, E.E.
AU  - Barth, T.K.
AU  - Lindermayr, C.
C1  - 56620
C2  - 47208
CY  - Great Clarendon St, Oxford Ox2 6dp, England
SP  - 2449-2463
TI  - S-nitrosothiol signaling is involved in regulating hydrogen peroxide metabolism of zinc-stressed Arabidopsis.
JO  - Plant Cell Physiol.
VL  - 60
IS  - 11
PB  - Oxford Univ Press
PY  - 2019
SN  - 0032-0781
ER  - 

TY  - JOUR
AB  - Toxic boron (B) concentrations cause impairments in several plant metabolic and physiological processes. Recently we reported that B toxicity led to a decrease in the transpiration rate of Arabidopsis plants in an ABA-dependent process within 24 h, which could indicate the occurrence of an adjustment of whole-plant water relations in response to this stress. Since plasma membrane intrinsic protein (PIP) aquaporins are key components influencing the water balance of plants because of their involvement in root water uptake and tissue hydraulic conductance, the aim of the present work was to study the effects of B toxicity on these important parameters affecting plant water status over a longer period of time. For this purpose, transpiration rate, water transport to the shoot and transcript levels of genes encoding four major PIP aquaporins were measured in Arabidopsis plants treated or not with a toxic B concentration. Our results indicate that, during the first 24 h of B toxicity, increased shoot ABA content would play a key role in reducing stomatal conductance, transpiration rate and, consequently, the water transport to the shoot. These physiological responses to B toxicity were maintained for up to 48 h of B toxicity despite shoot ABA content returning to control levels. In addition, B toxicity also caused the down-regulation of several genes encoding root and shoot aquaporins, which could reduce the cell to cell movement of water in plant tissues and, consequently, the water flux to shoot. All these changes in the water balance of plants under B toxicity could be a mechanism to prevent excess B accumulation in plant tissues.
AU  - Macho-Rivero, M.A.*
AU  - Herrera-Rodríguez, M.B.*
AU  - Brejcha, R.
AU  - Schäffner, A.
AU  - Tanaka, N.*
AU  - Fujiwara, T.*
AU  - González-Fontes, A.*
AU  - Camacho-Cristóbal, J.J.*
C1  - 52903
C2  - 44487
SP  - 836-844
TI  - Boron toxicity reduces water transport from root to shoot in arabidopsis plants. Evidence for a reduced transpiration rate and expression of major PIP aquaporin genes.
JO  - Plant Cell Physiol.
VL  - 59
IS  - 4
PY  - 2018
SN  - 0032-0781
ER  -