Time filter

Source Type

Zhao F.Y.,Shandong University of Technology | Hu F.,Shandong University of Technology | Han M.M.,Shandong University of Technology | Zhang S.Y.,Shandong Rice Research Institute | Liu W.,Shandong University of Technology
Russian Journal of Plant Physiology | Year: 2011

Changes of root growth and the expression of auxin and cell-cycle genes were analyzed in rice (Oryza sativa L. cv. Zhonghua No. 11) treated with Cd alone, Cd plus TIBA (2,3,5-triiodobenzoic acid, an inhibitor of polar auxin transport) or IBA (indole-3-butytric acid) and Cd plus Tiron (a scavenger of O 2 ·- or DDC (sodium diethyldithiocarbamate, a superoxide dismutase inhibitor). It was shown that Cd-stimulated rice root growth can be further enhanced by Cd plus IBA or DDC treatments but can be significantly suppressed following Cd together with Tiron or TIBA application. A comprehensive expression analysis of auxin genes, such as OsPID, OsPINs (Pin-Formeds), OsARFs (auxin response factors), and core cell-cycle genes, such as CDKs and CYCs in differently treated roots was conducted by semi-quantitative RT-PCR. The results showed that the expressions of 21 out of 35 tested auxin genes and 51 out of 63 tested cell-cycle genes were regulated by various treatments. Among the modified expression profiles of 72 genes, 53 and 59 genes were up- or down-regulated by auxin (including Cd plus TIBA or IBA treatments) and O 2 ·- (including Cd plus Tiron or DDC treatments), respectively. In the roots treated with Cd plus IBA or TIBA, the expressions of 39 genes changed differently from those under single Cd treated roots. Following Cd plus DDC or Tiron treatment, the transcripts of 36 genes were also altered differently from those under single Cd treatment. Obviously, auxin and O 2 ·- affected the expression of auxin and core cell-cycle genes under Cd stress. Taken together, our results indicated that in Cd-stressed rice plants, O 2 ·- and auxin were implicated in the redistribution of root growth and the expression of auxin and cell-cycle genes. © 2011 Pleiades Publishing, Ltd.

Zhao F.Y.,Shandong University of Technology | Hu F.,Shandong University of Technology | Zhang S.Y.,Shandong Rice Research Institute | Wang K.,Shandong University of Technology | And 2 more authors.
Environmental Science and Pollution Research | Year: 2013

This work aims to analyze the relationship between root growth, mitogen-activated protein kinase (MAPK), auxin signaling, and cell cycle-related gene expression in cadmium (Cd)-stressed rice. The role of MAPKs in auxin signal modification and cell cycle-related gene expression during root growth was investigated by disrupting MAPK signaling using the MAPKK inhibitor PD98059 (PD). Treatment with Cd caused a significant accumulation of Cd in the roots. A Cd-specific probe showed that Cd is mainly localized in the meristematic zone and vascular tissues. Perturbation of MAPK signaling using PD significantly suppressed root system growth under Cd stress. The transcription of six MAPK genes was inhibited by Cd compared to the control. Detection using DR5-GUS transgenic rice showed that the intensity and distribution pattern of GUS staining was similar in roots treated with PD or Cd, whereas in Cd plus PD-treated roots, the GUS staining pattern was similar to that of the control, which indicates a close association of MAPK signaling with auxin homeostasis under control and Cd stress conditions. The expression of most key genes of auxin signaling, including OsYUCCA, OsPIN, OsARF, and OsIAA, and of most cell cycle-related genes, was negatively regulated by MAPKs under Cd stress. These results suggest that the MAPK pathway plays specific roles in auxin signal transduction and in the control of the cell cycle in response to Cd stress. Altogether, MAPKs take part in the regulation of root growth via auxin signal variation and the modified expression of cell cycle-related genes in Cd-stressed rice. A working model for the function of MAPKs in rice root systems grown under Cd stress is proposed. © 2013 Springer-Verlag Berlin Heidelberg.

Zhao F.-Y.,Shandong University of Technology | Han M.-M.,Shandong University of Technology | Zhang S.-Y.,Shandong Rice Research Institute | Wang K.,Shandong University of Technology | And 3 more authors.
Journal of Integrative Plant Biology | Year: 2012

The link between root growth, H2O2, auxin signaling, and the cell cycle in cadmium (Cd)-stressed rice (Oryza sativa L. cv. Zhonghua No. 11) was analyzed in this study. Exposure to Cd induced a significant accumulation of Cd, but caused a decrease in zinc (Zn) content which resulted from the decreased expression of OsHMA9 and OsZIP. Analysis using a Cd-specific probe showed that Cd was mainly localized in the meristematic zone and vascular tissues. Formation and elongation of the root system were significantly promoted by 3-amino-1,2,4-triazole (AT), but were markedly inhibited by N,N'-dimethylthiourea (DMTU) under Cd stress. The effect of H2O2 on Cd-stressed root growth was further confirmed by examining a gain-of-function rice mutant (carrying catalase1 and glutathione-S-transferase) in the presence or absence of diphenylene iodonium. DR5-GUS staining revealed close associations between H2O2 and the concentration and distribution of auxin. H2O2 affected the expression of key genes, including OsYUCCA, OsPIN, OsARF, and OsIAA, in the auxin signaling pathway in Cd-treated plants. These results suggest that H2O2 functions upstream of the auxin signaling pathway. Furthermore, H2O2 modified the expression of cell-cycle genes in Cd-treated roots. The effects of H2O2 on root system growth are therefore linked to auxin signal modification and to variations in the expression of cell-cycle genes in Cd-stressed rice. A working model for the effects of H2O2 on Cd-stressed root system growth is thus proposed and discussed in this paper. © 2012 Institute of Botany, Chinese Academy of Sciences.

Zhao F.Y.,Shandong University of Technology | Wang K.,Shandong University of Technology | Zhang S.Y.,Shandong Rice Research Institute | Ren J.,Shandong University of Technology | And 2 more authors.
Acta Physiologiae Plantarum | Year: 2014

We studied the link between abscisic acid (ABA), auxin, MAPK (mitogen-activated protein kinase) signaling, and the cell cycle in cadmium (Cd)-stressed rice (Oryza sativa L. cv. Zhonghua No. 11) roots. ABA can partially compensate for root growth inhibition and counteract over-accumulation of auxin caused by Cd. GUS staining of rice plants harboring DR5-GUS showed that ABA affects auxin distribution in Cd-stressed roots. Detection using DRB (5,6-dichlorobenzimidazole 1-β-d-ribofuranoside, an RNA synthesis inhibitor), MG132 (a protein degradation inhibitor), BFA (brefeldin A, a protein transport inhibitor), and TIBA (2,3,5-triiodobenzoic acid, a polar auxin transport inhibitor) revealed that ABA regulates the distribution of auxin via transcription, protein degradation, and transport pathways under Cd stress. Several genes related to ABA and MAPK, key components of the auxin signaling pathway, and the cell cycle were differentially regulated by Cd plus ABA vs. Cd plus tungstate (TS) (a ABA biosynthesis inhibitor) at 7 days or 11 days of treatment in roots, indicating that ABA levels affect the transcription of these genes, and that these genes are differentially regulated by ABA in rice seedlings at different developmental stages. Furthermore, the expression of some of these genes differed between Cd + ABA/TS-treated plants and plants treated with TS or ABA alone, suggesting that ABA signaling serves specific functions in the regulation of gene expression under Cd stress. Overall, these results suggest that ABA coordinates auxin and MAPK signaling and the cell cycle in response to Cd stress. The ABA signal transduction pathways in Cd-stressed rice plants are discussed. © 2014 Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków.

Zhao J.,Shandong Rice Research Institute | Zhao J.,Shandong Normal University | Zhou J.-J.,Shandong Rice Research Institute | Wang Y.-Y.,Shandong Rice Research Institute | And 3 more authors.
Rice Science | Year: 2013

Phytochromes in rice are encoded by a gene family composed of three members, PHYA, PHYB, and PHYC. Through characterizing the phytochrome mutants and wild type (WT) in terms of photomorphogenesis, roles of individual phytochromes have been preliminarily explored in regulating rice de-etiolation, flowering time and fertility. However, little information has been reported about whether or how phytochromes affect chlorophyll biosynthesis and chloroplast development in rice. In this study, we compared the chlorophyll contents of wild type and the phyA, phyB and phyAphyB mutants grown under either white light (WL) or red light (R). The results suggest that phyB perceives R to positively regulate chlorophyll biosynthesis, while the role of phyA can be detected only in the phyB-deficient mutant. Analyses of the expression levels of genes involved in chlorophyll biosynthesis revealed that phytochromes affected the chlorophyll biosynthesis by regulating protochlorophyll oxidoreductase A (PORA) expression. The role of phyB in chloroplast development was also analyzed, and the results suggest that phyB perceives R to regulate chloroplast development by affecting the numbers of chloroplasts and grana, as well as the chloroplast membrane system. © 2013 China National Rice Research Institute.

Tian S.,Shandong Agricultural University | Wang Y.,Shandong Rice Research Institute | Ning T.,Shandong Agricultural University | Zhao H.,Shandong Agricultural University | And 4 more authors.
PLoS ONE | Year: 2013

Appropriate tillage plays an important role in mitigating the emissions of greenhouse gases (GHG) in regions with higher crop yields, but the emission situations of some reduced tillage systems such as subsoiling, harrow tillage and rotary tillage are not comprehensively studied. The objective of this study was to evaluate the emission characteristics of GHG (CH4 and N2O) under four reduced tillage systems from October 2007 to August 2009 based on a 10-yr tillage experiment in the North China Plain, which included no-tillage (NT) and three reduced tillage systems of subsoil tillage (ST), harrow tillage (HT) and rotary tillage (RT), with the conventional tillage (CT) as the control. The soil under the five tillage systems was an absorption sink for CH4 and an emission source for N2O. The soil temperature positive impacted on the CH4 absorption by the soils of different tillage systems, while a significant negative correlation was observed between the absorption and soil moisture. The main driving factor for increased N2O emission was not the soil temperature but the soil moisture and the content of nitrate. In the two rotation cycle of wheat-maize system (10/2007-10/2008 and 10/2008-10/2009), averaged cumulative uptake fluxes of CH4 under CT, ST, HT, RT and NT systems were approximately 1.67, 1.72, 1.63, 1.77 and 1.17 t ha-1 year-1, respectively, and meanwhile, approximately 4.43, 4.38, 4.47, 4.30 and 4.61 t ha-1 year-1 of N2O were emitted from soil of these systems, respectively. Moreover, they also gained 33.73, 34.63, 32.62, 34.56 and 27.54 t ha-1 yields during two crop-rotation periods, respectively. Based on these comparisons, the rotary tillage and subsoiling mitigated the emissions of CH4 and N2O as well as improving crop productivity of a wheat-maize cropping system. © 2013 Tian et al.

Zhao J.,Chinese Academy of Agricultural Sciences | Wang T.,Chinese Academy of Agricultural Sciences | Wang M.,Chinese Academy of Agricultural Sciences | Liu Y.,Chinese Academy of Agricultural Sciences | And 8 more authors.
Plant and Cell Physiology | Year: 2014

Strigolactones (SLs) are a novel class of plant hormones that inhibit shoot branching. Currently, two proteins in rice are thought to play crucial roles in SL signal transduction. DWARF14 (D14), an α/β hydrolase, is responsible for SL perception, while DWARF3 (D3), an F-box protein with leucine-rich repeats, is essential for SL signal transduction. However, how these two proteins transmit SL signals to downstream factors remains unclear. Here, we characterized a high-tillering dwarf rice mutant, gsor300097, which is insensitive to GR24, a synthetic analog of SL. Mapping and sequencing analysis showed that gsor300097 is a novel allelic mutant of D3, in which a nonsense mutation truncates the protein from 720 to 527 amino acids. The D3 gene was strongly expressed in root, leaf, shoot base and panicle. Nuclear-localized F-box protein D3 played a role in the SCF complex by interacting with OSK1, OSK5 or OSK20 and OsCullin1. In addition, D3 associated with D14 in a GR24-dependent manner in vivo. Taken together, our findings suggested that D3 assembled into an SCFD3 complex and associated with D14 to suppress rice shoot branching. © 2014 The Author.

PubMed | James Hutton Institute, Shandong Rice Research Institute, Zhejiang Academy of Agricultural Sciences and Zhejiang University
Type: | Journal: The New phytologist | Year: 2016

Plant hormones play a vital role in plant immune responses. However, in contrast to the relative wealth of information on hormone-mediated immunity in dicot plants, little information is available on monocot-virus defense systems. We used a high-throughput-sequencing approach to compare the global gene expression of Rice black-streaked dwarf virus (RBSDV)-infected rice plants with that of healthy plants. Exogenous hormone applications and transgenic rice were used to test RBSDV infectivity and pathogenicity. Our results revealed that the jasmonic acid (JA) pathway was induced while the brassinosteroid (BR) pathway was suppressed in infected plants. Foliar application of methyl jasmonate (MeJA) or brassinazole (BRZ) resulted in a significant reduction in RBSDV incidence, while epibrassinolide (BL) treatment increased RBSDV infection. Infection studies using coi1-13 and Go mutants demonstrated JA-mediated resistance and BR-mediated susceptibility to RBSDV infection. A mixture of MeJA and BL treatment resulted in a significant reduction in RBSDV infection compared with a single BL treatment. MeJA application efficiently suppressed the expression of BR pathway genes, and this inhibition depended on the JA coreceptor OsCOI1. Collectively, our results reveal that JA-mediated defense can suppress the BR-mediated susceptibility to RBSDV infection.

PubMed | Chinese Academy of Agricultural Sciences and Shandong Rice Research Institute
Type: Journal Article | Journal: PloS one | Year: 2016

Rice is a model plant species for the study of cellulose biosynthesis. We isolated a mutant, S1-24, from ethyl methanesulfonate (EMS)-treated plants of the japonica rice cultivar, Nipponbare. The mutant exhibited brittle culms and other pleiotropic phenotypes such as dwarfism and partial sterility. The brittle culms resulted from reduced mechanical strength due to a defect in thickening of the sclerenchyma cell wall and reduced cellulose content in the culms of the S1-24 mutant. Map-based gene cloning and a complementation assay showed that phenotypes of the S1-24 mutant were caused by a recessive point mutation in the OsCESA7 gene, which encodes cellulose synthase A subunit 7. The missense mutation changed the highly conserved C40 to Y in the zinc finger domain. The OsCESA7 gene is expressed predominantly in the culm at the mature stage, particularly in mechanical tissues such as vascular bundles and sclerenchyma cells, consistent with the brittle phenotype in the culm. These results indicate that OsCESA7 plays an important role in cellulose biosynthesis and plant growth.

PubMed | Chinese Academy of Agricultural Sciences, Shandong Rice Research Institute and Qingdao Agricultural University
Type: Journal Article | Journal: PloS one | Year: 2015

Leaf morphology is closely associated with cell division. In rice, mutations in Narrow leaf 1 (NAL1) show narrow leaf phenotypes. Previous studies have shown that NAL1 plays a role in regulating vein patterning and increasing grain yield in indica cultivars, but its role in leaf growth and development remains unknown. In this report, we characterized two allelic mutants of NARROW LEAF1 (NAL1), nal1-2 and nal1-3, both of which showed a 50% reduction in leaf width and length, as well as a dwarf culm. Longitudinal and transverse histological analyses of leaves and internodes revealed that cell division was suppressed in the anticlinal orientation but enhanced in the periclinal orientation in the mutants, while cell size remained unaltered. In addition to defects in cell proliferation, the mutants showed abnormal midrib in leaves. Map-based cloning revealed that nal1-2 is a null allelic mutant of NAL1 since both the whole promoter and a 404-bp fragment in the first exon of NAL1 were deleted, and that a 6-bp fragment was deleted in the mutant nal1-3. We demonstrated that NAL1 functions in the regulation of cell division as early as during leaf primordia initiation. The altered transcript level of G1- and S-phase-specific genes suggested that NAL1 affects cell cycle regulation. Heterogeneous expression of NAL1 in fission yeast (Schizosaccharomyces pombe) further supported that NAL1 affects cell division. These results suggest that NAL1 controls leaf width and plant height through its effects on cell division.

Loading Shandong Rice Research Institute collaborators
Loading Shandong Rice Research Institute collaborators