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1.
Plant Cell ; 34(11): 4366-4387, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-35972379

RESUMO

Ethylene plays essential roles in adaptive growth of rice (Oryza sativa). Understanding of the crosstalk between ethylene and auxin (Aux) is limited in rice. Here, from an analysis of the root-specific ethylene-insensitive rice mutant mao hu zi 10 (mhz10), we identified the tryptophan aminotransferase (TAR) MHZ10/OsTAR2, which catalyzes the key step in indole-3-pyruvic acid-dependent Aux biosynthesis. Genetically, OsTAR2 acts downstream of ethylene signaling in root ethylene responses. ETHYLENE INSENSITIVE3 like1 (OsEIL1) directly activated OsTAR2 expression. Surprisingly, ethylene induction of OsTAR2 expression still required the Aux pathway. We also show that Os indole-3-acetic acid (IAA)1/9 and OsIAA21/31 physically interact with OsEIL1 and show promotive and repressive effects on OsEIL1-activated OsTAR2 promoter activity, respectively. These effects likely depend on their EAR motif-mediated histone acetylation/deacetylation modification. The special promoting activity of OsIAA1/9 on OsEIL1 may require both the EAR motifs and the flanking sequences for recruitment of histone acetyltransferase. The repressors OsIAA21/31 exhibit earlier degradation upon ethylene treatment than the activators OsIAA1/9 in a TIR1/AFB-dependent manner, allowing OsEIL1 activation by activators OsIAA1/9 for OsTAR2 expression and signal amplification. This study reveals a positive feedback regulation of ethylene signaling by Aux biosynthesis and highlights the crosstalk between ethylene and Aux pathways at a previously underappreciated level for root growth regulation in rice.


Assuntos
Etilenos , Ácidos Indolacéticos , Oryza , Raízes de Plantas , Triptofano Transaminase , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Triptofano Transaminase/genética , Triptofano Transaminase/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(36): e2121671119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037381

RESUMO

Carbohydrate partitioning between the source and sink tissues plays an important role in regulating plant growth and development. However, the molecular mechanisms regulating this process remain poorly understood. In this study, we show that elevated auxin levels in the rice dao mutant cause increased accumulation of sucrose in the photosynthetic leaves but reduced sucrose content in the reproductive organs (particularly in the lodicules, anthers, and ovaries), leading to closed spikelets, indehiscent anthers, and parthenocarpic seeds. RNA sequencing analysis revealed that the expression of AUXIN RESPONSE FACTOR 18 (OsARF18) and OsARF2 is significantly up- and down-regulated, respectively, in the lodicule of dao mutant. Overexpression of OsARF18 or knocking out of OsARF2 phenocopies the dao mutant. We demonstrate that OsARF2 regulates the expression of OsSUT1 through direct binding to the sugar-responsive elements (SuREs) in the OsSUT1 promoter and that OsARF18 represses the expression of OsARF2 and OsSUT1 via direct binding to the auxin-responsive element (AuxRE) or SuRE in their promoters, respectively. Furthermore, overexpression of OsSUT1 in the dao and Osarf2 mutant backgrounds could largely rescue the spikelets' opening and seed-setting defects. Collectively, our results reveal an auxin signaling cascade regulating source-sink carbohydrate partitioning and reproductive organ development in rice.


Assuntos
Metabolismo dos Carboidratos , Flores , Ácidos Indolacéticos , Oryza , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Ácidos Indolacéticos/metabolismo , Mutação , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sacarose/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(30): e2201072119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35858424

RESUMO

Soil compaction represents a major agronomic challenge, inhibiting root elongation and impacting crop yields. Roots use ethylene to sense soil compaction as the restricted air space causes this gaseous signal to accumulate around root tips. Ethylene inhibits root elongation and promotes radial expansion in compacted soil, but its mechanistic basis remains unclear. Here, we report that ethylene promotes abscisic acid (ABA) biosynthesis and cortical cell radial expansion. Rice mutants of ABA biosynthetic genes had attenuated cortical cell radial expansion in compacted soil, leading to better penetration. Soil compaction-induced ethylene also up-regulates the auxin biosynthesis gene OsYUC8. Mutants lacking OsYUC8 are better able to penetrate compacted soil. The auxin influx transporter OsAUX1 is also required to mobilize auxin from the root tip to the elongation zone during a root compaction response. Moreover, osaux1 mutants penetrate compacted soil better than the wild-type roots and do not exhibit cortical cell radial expansion. We conclude that ethylene uses auxin and ABA as downstream signals to modify rice root cell elongation and radial expansion, causing root tips to swell and reducing their ability to penetrate compacted soil.


Assuntos
Ácido Abscísico , Etilenos , Ácidos Indolacéticos , Oryza , Raízes de Plantas , Ácido Abscísico/metabolismo , Etilenos/metabolismo , Ácidos Indolacéticos/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Mutação , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Solo
5.
Proc Natl Acad Sci U S A ; 119(26): e2122582119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35733265

RESUMO

Plants use photoperiodism to activate flowering in response to a particular daylength. In rice, flowering is accelerated in short-day conditions, and even a brief exposure to light during the dark period (night-break) is sufficient to delay flowering. Although many of the genes involved in controlling flowering in rice have been uncovered, how the long- and short-day flowering pathways are integrated, and the mechanism of photoperiod perception is not understood. While many of the signaling components controlling photoperiod-activated flowering are conserved between Arabidopsis and rice, flowering in these two systems is activated by opposite photoperiods. Here we establish that photoperiodism in rice is controlled by the evening complex (EC). We show that mutants in the EC genes LUX ARRYTHMO (LUX) and EARLY FLOWERING3 (ELF3) paralogs abolish rice flowering. We also show that the EC directly binds and suppresses the expression of flowering repressors, including PRR37 and Ghd7. We further demonstrate that light acts via phyB to cause a rapid and sustained posttranslational modification of ELF3-1. Our results suggest a mechanism by which the EC is able to control both long- and short-day flowering pathways.


Assuntos
Flores , Oryza , Fotoperíodo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Flores/efeitos da radiação , Regulação da Expressão Gênica de Plantas , Luz , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
Ying Yong Sheng Tai Xue Bao ; 33(2): 405-414, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35229514

RESUMO

Light simplified cultivation and high quality rice are the main directions of rice production in China. Meteorological factors are the most important environmental factors affecting rice growth and yield. Few studies examined the relationship between rice yield and microclimate under different light simplified cultivation modes. To explore the relationship between rice yield and climatic factors (temperature, sunshine and water) at different growth stages of hybrid rice under different forecrops in southwest China, we carried out a split-plot design experiment in 2019 and 2020, with two forecrops of green cabbage and rape as the main plot, and three planting methods, direct-seeding, blanket-transplanting, and artificial transplanting as the subplots, taking Yixiangyou 2115 as the experimental variety. Results showed that compared with rape-paddy cropping system, cabbage-paddy cropping system significantly improved the accumulated temperature and precipitation production efficiency and consequently improved the effective panicles, setting rate, and 1000-grain weight. The yield was increased by 12.7% and 8.3% under cabbage-paddy and rape-paddy cropping system, respectively. Compared with manual transplanting, mechanical transplanting improved effective panicles, production efficiency of radiation, accumulated temperature and precipitation, and the radiation use efficiency of grain during the whole growth period. The mean yield was increased by 4.6% in 2019 and 2020. However, the above parameters of direct-seeding significantly decreased, but the yield decreased by 8.7%. Compared with 2019, mechanical transplanting and artificial transplanting were sown one month earlier in 2020 under the same stubble, which shortened growth period, reduced air temperature, and increased precipitation after flowering, leading to a significant decrease in effective accumulated temperature and light radiation; production efficiency of accumulated temperature, light energy, and precipitation; and utilization efficiency of light energy of grain, spikelets per panicle, setting rate, and 1000-grain weight. However, the yield was significantly reduced. Partial least squares regression analysis was used to establish the production forecast equation of standardized regression coefficients of meteorological factors. There was a positive correlation between rice yield and effective accumulated temperature and total radiation during the growth stage or the whole growth period. In addition, there was a significant negative correlation between rice yield and precipitation during the whole growth period. In conclusion, mechanical transplanting under cabbage-paddy cropping system was a rice planting method that optimised the seasonal sunshine and temperature resources in southwest China. The method facilitated the full utilization of temperature and sunshine resources, resulting in high yield. However, it was not advisable to sow or transplant too early.


Assuntos
Agricultura , Brassica , Oryza , Agricultura/métodos , Brassica/crescimento & desenvolvimento , China , Grão Comestível , Oryza/crescimento & desenvolvimento , Temperatura
7.
ScientificWorldJournal ; 2022: 5129423, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237114

RESUMO

This study was conducted in Tanahun district of Gandaki Province, Nepal, to analyze the land cover change over two decades, the migration effect in land cover, and the impact caused in crop production by Rhesus macaque. Landsat TM/ETM+ for land use of 2000 and 2010 extracted by ICIMOD and Landsat 8 OLI/TIRS satellite images for land cover 2019 were downloaded from the USGS website. A purposive sample for household survey was carried out based on crops damaged by the monkey. Two hundred and fifty households were taken as samples. The Landsat images were analyzed by ArcGIS, and the social data were analyzed using SPSS and MS Excel. Land cover change data revealed increment of forest cover from 36.57% to 40.91% and drastic decrease in agriculture crops from 57.52% to 43.78% in the period of 20 years. The accuracy of the data showed overall classification accuracy of 86.11%, 81.08%, and 75% with overall kappa statistics 0.83, 0.77, and 0.74, respectively. The migration effect in the land cover was related to remittance and migrated members and found a significant positive relationship. Analyzing the trend of production with an increase in the forest cover, 21% decrease in paddy, 5% decrease in maize, and 26% decrease in millet were found as compared to the production in 2000. The econometric model concluded that the quantity of crop damage was negatively significant in relation to distance from forest and distance from water body while positively significant to distance from settlements and distance from owner's home. The quantity of crop damage was estimated 113.89 kg per household, and the cost was 78.82 USD. This study recommends active forest management; regular thinning, and weeding. Remittance generated should be invested in the agriculture field by the households. Damage relief should be made available for the damage cost by Rhesus macaque.


Assuntos
Produção Agrícola , Produção Agrícola/métodos , Produção Agrícola/estatística & dados numéricos , Meio Ambiente , Florestas , Pradaria , Milhetes/crescimento & desenvolvimento , Modelos Estatísticos , Nepal , Oryza/crescimento & desenvolvimento , Imagens de Satélites , Zea mays/crescimento & desenvolvimento
8.
Int J Mol Sci ; 23(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35163461

RESUMO

Brown planthopper (BPH, Nilaparvata lugens Stal.) is the most damaging rice pest affecting stable rice yields worldwide. Currently, methods for controlling BPH include breeding a BPH-resistant cultivar and using synthetic pesticides. Nevertheless, the continuous cultivation of resistant cultivars allows for the emergence of various resistant races, and the use of synthetic pesticides can induce environmental pollution as well as the emergence of unpredictable new pest species. As plants cannot migrate to other locations on their own to combat various stresses, the production of secondary metabolites allows plants to protect themselves from stress and tolerate their reproduction. Pesticides using natural products are currently being developed to prevent environmental pollution and ecosystem disturbance caused by synthetic pesticides. In this study, after BPH infection in rice, chrysoeriol7 (C7), a secondary metabolite that induces resistance against BPH, was assessed. After C7 treatment and BPH infection, relative expression levels of the flavonoid-related genes were elevated, suggesting that in plants subjected to BPH, compounds related to flavonoids, among the secondary metabolites, play an important role in inducing resistance. The plant-derived natural compound chrysoeriol7 can potentially thus be used to develop environmentally friendly pesticides. The suggested control of BPH can be effectively used to alleviate concerns regarding environmental pollution and to construct a relatively safe rice breeding environment.


Assuntos
Resistência à Doença , Flavonas/isolamento & purificação , Hemípteros/crescimento & desenvolvimento , Repelentes de Insetos/isolamento & purificação , Oryza/crescimento & desenvolvimento , Animais , Vias Biossintéticas , Flavonas/química , Flavonas/farmacologia , Regulação da Expressão Gênica de Plantas , Química Verde , Hemípteros/efeitos dos fármacos , Repelentes de Insetos/química , Repelentes de Insetos/farmacologia , Oryza/química , Oryza/parasitologia , Proteínas de Plantas/genética , Metabolismo Secundário
9.
Int J Mol Sci ; 23(3)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35163531

RESUMO

Flowering is a key agronomic trait that influences adaptation and productivity. Previous studies have indicated the genetic complexity associated with the flowering response in a photoinsensitive weedy rice accession PSRR-1 despite the presence of a photosensitive allele of a key flowering gene Hd1. In this study, we used whole-genome and RNA sequencing data from both cultivated and weedy rice to add further insights. The de novo assembly of unaligned sequences predicted 225 genes, in which 45 were specific to PSRR-1, including two genes associated with flowering. Comparison of the variants in PSRR-1 with the 3K rice genome (RG) dataset identified unique variants within the heading date QTLs. Analyses of the RNA-Seq result under both short-day (SD) and long-day (LD) conditions revealed that many differentially expressed genes (DEGs) colocalized with the flowering QTLs, and some DEGs such as Hd1, OsMADS56, Hd3a, and RFT1 had unique variants in PSRR-1. Ehd1, Hd1, OsMADS15, and OsMADS56 showed different alternate splicing (AS) events between genotypes and day length conditions. OsMADS56 was expressed in PSRR-1 but not in Cypress under both LD and SD conditions. Based on variations in both sequence and expression, the unique flowering response in PSRR-1 may be due to the high-impact variants of flowering genes, and OsMADS56 is proposed as a key regulator for its day-neutral flowering response.


Assuntos
Perfilação da Expressão Gênica/métodos , Oryza/crescimento & desenvolvimento , Locos de Características Quantitativas , Sequenciamento Completo do Genoma/métodos , Mapeamento Cromossômico , Produtos Agrícolas/classificação , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Oryza/classificação , Oryza/genética , Fotoperíodo , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , RNA-Seq
10.
Int J Mol Sci ; 23(3)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35163547

RESUMO

Salinity is one of the most common unfavorable environmental conditions that limits plant growth and development, ultimately reducing crop productivity. To investigate the underlying molecular mechanism involved in the salinity response in rice, we initially screened 238 rice cultivars after salt treatment at the seedling stage and identified two highly salt-tolerant cultivars determined by the relative damage rate parameter. The majority of cultivars (94.1%) were ranked as salt-sensitive and highly salt-sensitive. Transcriptome profiling was completed in highly salt-tolerant, moderately salt-tolerant, and salt-sensitive under water and salinity treatments at the seedling stage. Principal component analysis displayed a clear distinction among the three cultivars under control and salinity stress conditions. Several starch and sucrose metabolism-related genes were induced after salt treatment in all genotypes at the seedling stage. The results from the present study enable the identification of the ascorbate glutathione pathway, potentially participating in the process of plant response to salinity in the early growth stage. Our findings also highlight the significance of high-affinity K+ uptake transporters (HAKs) and high-affinity K+ transporters (HKTs) during salt stress responses in rice seedlings. Collectively, the cultivar-specific stress-responsive genes and pathways identified in the present study act as a useful resource for researchers interested in plant responses to salinity at the seedling stage.


Assuntos
Perfilação da Expressão Gênica/métodos , Redes e Vias Metabólicas , Oryza/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica de Plantas , Genótipo , Germinação , Oryza/classificação , Oryza/genética , Proteínas de Plantas/genética , Salinidade , Estresse Salino , Plântula/classificação , Plântula/genética , Amido/biossíntese , Sacarose/metabolismo
11.
Sci Rep ; 12(1): 2694, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177664

RESUMO

The application of slow-release fertilizer is an effective way to satisfy the demand for nutrients of crops. The objective of present study was to investigate the microbial community characteristics in rice rhizosphere soil under different fertilization modes of slow-release fertilizer. Three fertilization modes of slow-release fertilizer, i.e., (CK) manually broadcasted on the soil surface at 300 kg·ha-1 before transplanting and then same fertilizer rate was applied at the same way one week after transplanting; (SF) 10 cm depth mechanized placement at 600 kg·ha-1 during the transplanting; (DSF) 10 cm depth mechanized placement at 480 kg·ha-1 during the transplanting, were adopt in the field experiment. The results showed that SF and DSF treatments promoted richness (ACE and Chao1 values) and diversity (Shannon value) of rice rhizosphere microorganisms compared with CK treatment. Compared with CK, SF treatment increased relative abundances of Planctomycetes and decreased relative abundance of Nitrospirae, DSF treatments increased relative abundances of Deltaproteobacteria. Moreover, higher relative abundances of Paenibacillus and Sphingomonas were recorded in DSF treatment than CK. In addition, the partial factor productivity (PFP) deep placement of slow-release fertilizer treatment was significantly higher than that of CK treatment. DSF treatment increased the yield by 16.61% compared with CK treatment while reducing fertilizer input by 20%. In conclusion, compared with broadcasting, deep placement of slow-release fertilizer could improve the structure, distribution, and diversity of the microbial community in rice rhizosphere soil, and increase the utilization rate of fertilizers, and increase rice yield.


Assuntos
Fertilizantes , Microbiota/efeitos dos fármacos , Oryza , Rizosfera , Microbiologia do Solo , Oryza/crescimento & desenvolvimento , Oryza/microbiologia
12.
Sci Rep ; 12(1): 2096, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136146

RESUMO

The response of root growth to various osmotic potentials is quite important in assessing the drought resistance of rice. This study modeled seminal root growth by applying consecutive polyethylene glycol (PEG) treatments (from 0 to 25%, 1% step), mathematical equations and noncontact image analysis to quantitatively evaluate the root response. Treatment began after seeds were germinated, and root growth was recorded by a digital camera every day from 7 to 20 days after seeding (DAS). Although the seminal root length (SRL) measured by image analysis slightly varied with DAS, the equations explained the differences in SRL increases under each PEG concentration relatively well (R2 = 0.774). The equations also suggested that the maximum seminal root length was observed at 5.9% PEG. This numerical characterization of root growth is an effective means of evaluating drought resistance.


Assuntos
Modelos Biológicos , Oryza/crescimento & desenvolvimento , Pressão Osmótica , Raízes de Plantas/crescimento & desenvolvimento , Polietilenoglicóis
13.
Int J Mol Sci ; 23(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35163510

RESUMO

In order to separate transformed cells from non-transformed cells, antibiotic selectable marker genes are usually utilized in genetic transformation. After obtaining transgenic plants, it is often necessary to remove the marker gene from the plant genome in order to avoid regulatory issues. However, many marker-free systems are time-consuming and labor-intensive. Homology-directed repair (HDR) is a process of homologous recombination using homologous arms for efficient and precise repair of DNA double-strand breaks (DSBs). The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein-9 (Cas9) system is a powerful genome editing tool that can efficiently cause DSBs. Here, we isolated a rice promoter (Pssi) of a gene that highly expressed in stem, shoot tip and inflorescence, and established a high-efficiency sequence-excision strategy by using this Pssi to drive CRISPR/Cas9-mediated HDR for marker free (PssiCHMF). In our study, PssiCHMF-induced marker gene deletion was detected in 73.3% of T0 plants and 83.2% of T1 plants. A high proportion (55.6%) of homozygous marker-excised plants were obtained in T1 progeny. The recombinant GUS reporter-aided analysis and its sequencing of the recombinant products showed precise deletion and repair mediated by the PssiCHMF method. In conclusion, our CRISPR/Cas9-mediated HDR auto-excision method provides a time-saving and efficient strategy for removing the marker genes from transgenic plants.


Assuntos
Edição de Genes/métodos , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Sistemas CRISPR-Cas , Embaralhamento de DNA , Flores/genética , Flores/crescimento & desenvolvimento , Recombinação Homóloga , Oryza/genética , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Caules de Planta/genética , Caules de Planta/crescimento & desenvolvimento
14.
Int J Mol Sci ; 23(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35163555

RESUMO

Iron (Fe) homeostasis in plants is governed by a complex network of regulatory elements and transcription factors (TFs), as both Fe toxicity and deficiency negatively impact plant growth and physiology. The Fe homeostasis network is well characterized in Arabidopsis thaliana and remains poorly understood in monocotyledon species such as rice (Oryza sativa L.). Recent investigation of the rice Fe homeostasis network revealed OsIRO3, a basic Helix-Loop-Helix (bHLH) TF as a putative negative regulator of genes involved in Fe uptake, transport, and storage. We employed CRISPR-Cas9 gene editing to target the OsIRO3 coding sequence and generate two independent T-DNA-free, loss-of-function iro3 mutants in rice cv. Nipponbare. The iro3 mutant plants had similar phenotype under nutrient-sufficient conditions and had stunted growth under Fe-deficient conditions, relative to a T-DNA free, wild-type control (WT). Under Fe deficiency, iro3 mutant shoots had reduced expression of Fe chelator biosynthetic genes (OsNAS1, OsNAS2, and OsNAAT1) and upregulated expression of an Fe transporter gene (OsYSL15), relative to WT shoots. We place our results in the context of the existing literature and generate a model describing the role of OsIRO3 in rice Fe homeostasis and reinforce the essential function of OsIRO3 in the rice Fe deficiency response.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ferro/metabolismo , Oryza/crescimento & desenvolvimento , Sistemas CRISPR-Cas , Ferroptose , Edição de Genes , Regulação da Expressão Gênica de Plantas , Homeostase , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
15.
BMC Plant Biol ; 22(1): 70, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35176996

RESUMO

BACKGROUND: Seed germination is a crucial process, which determines the initiation of seed plant life cycle. The early events during this important life cycle transition that called early seed germination is defined as initially water uptake plus radicle growing out of the covering seed layers. However, a specific genome-wide analysis of early seed germination in rice is still obscure. RESULTS: In this study, the physiological characteristics of rice seed during seed germination are determined to define key points of early seed germination. Transcriptome analyses of early phase of seed germination provided deeper insight into the genetic regulation landscape. Many genes involved in starch-to-sucrose transition were differentially expressed, especially alpha-amylase 1b and beta-amylase 2, which were predominantly expressed. Differential exon usage (DEU) genes were identified, which were significantly enriched in the pathway of starch and sucrose metabolism, indicating that DEU events were critical for starch-to-sucrose transition at early seed germination. Transcription factors (TFs) were also dramatic expressed, including the abscisic acid (ABA) responsive gene, OsABI5, and gibberellic acid (GA) responsive genes, GAI. Moreover, GAI transactivated GA responsive gene, GAMYB in vivo, indicating a potential pathway involved in early seed germination process. In addition, CBL-interacting protein kinase (CIPK) genes, such as CIPK13, CIPK14 and CIPK17 were potentially interacted with other proteins, indicating its pivotal role at early seed germination. CONCLUSION: Taken together, gene regulation of early seed germination in rice was complex and protein-to-gene or protein-to-protein interactions were indispensable.


Assuntos
Germinação/genética , Oryza/genética , Sementes/genética , Ácido Abscísico/metabolismo , Éxons , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Mapas de Interação de Proteínas/genética , Sementes/crescimento & desenvolvimento , Amido/genética , Amido/metabolismo , Sacarose/metabolismo , Fatores de Transcrição/genética
16.
Int J Mol Sci ; 23(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35162955

RESUMO

The effect of exogenously-applied ethylene sourced from ethephon (2-chloroethyl phosphonic acid)was studied on photosynthesis, carbohydrate metabolism, and high-temperature stress tolerance in Taipei-309 and Rasi cultivars of rice (Oryza sativa L.). Heat stress increased the content of H2O2 and thiobarbituric acid reactive substances (TBARS)more in Rasi than Taipei-309. Further, a significant decline in sucrose, starch, and carbohydrate metabolism enzyme activity and photosynthesis was also observed in response to heat stress. The application of ethephon reduced H2O2 and TBARS content by enhancing the enzymatic antioxidant defense system and improved carbohydrate metabolism, photosynthesis, and growth more conspicuously in Taipei-309 under heat stress. The ethephon application enhanced photosynthesis by up-regulating the psbA and psbB genes of photosystem II in heat-stressed plants. Interestingly, foliar application of ethephoneffectively down-regulated high-temperature-stress-induced elevated ethylene biosynthesis gene expression. Overall, ethephon application optimized ethylene levels under high-temperature stress to regulate the antioxidant enzymatic system and carbohydrate metabolism, reducing the adverse effects on photosynthesis. These findings suggest that ethylene regulates photosynthesis via carbohydrate metabolism and the antioxidant system, thereby influencing high-temperature stress tolerance in rice.


Assuntos
Antioxidantes/metabolismo , Metabolismo dos Carboidratos/efeitos dos fármacos , Compostos Organofosforados/farmacologia , Oryza/crescimento & desenvolvimento , Complexo de Proteína do Fotossistema II/genética , Etilenos/química , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Compostos Organofosforados/química , Oryza/efeitos dos fármacos , Oryza/genética , Oryza/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Proteínas de Plantas/genética , Termotolerância , Tiobarbitúricos/metabolismo
17.
Int J Mol Sci ; 23(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35163057

RESUMO

Low phosphate (Pi) availability and high aluminum (Al) toxicity constitute two major plant mineral nutritional stressors that limit plant productivity on acidic soils. Advances toward the identification of genes and signaling networks that are involved in both stresses in model plants such as Arabidopsis thaliana and rice (Oryza sativa), and in other plants as well have revealed that some factors such as organic acids (OAs), cell wall properties, phytohormones, and iron (Fe) homeostasis are interconnected with each other. Moreover, OAs are involved in recruiting of many plant-growth-promoting bacteria that are able to secrete both OAs and phosphatases to increase Pi availability and decrease Al toxicity. In this review paper, we summarize these mutual mechanisms by which plants deal with both Al toxicity and P starvation, with emphasis on OA secretion regulation, plant-growth-promoting bacteria, transcription factors, transporters, hormones, and cell wall-related kinases in the context of root development and root system architecture remodeling that plays a determinant role in improving P use efficiency and Al resistance on acidic soils.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Fosfatos/deficiência , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Bactérias/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Ferro/metabolismo , Oryza/metabolismo , Oryza/microbiologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia
18.
Int J Mol Sci ; 23(3)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35163767

RESUMO

Salt stress is a major limiting factor in crop production and yield in many regions of the world. The objective of this study was to identify the genes responsible for salt tolerance in Thai rice populations. We performed a genome-wide association study with growth traits, relative water content, and cell membrane stability at the seedling stage, and predicted 25 putative genes. Eleven of them were located within previously reported salt-tolerant QTLs (ST-QTLs). OsCRN, located outside the ST-QTLs, was selected for gene characterization using the Arabidopsis mutant line with T-DNA insertion in the orthologous gene. Mutations in the AtCRN gene led to the enhancement of salt tolerance by increasing the ability to maintain photosynthetic pigment content and relative water content, while the complemented lines with ectopic expression of OsCRN showed more susceptibility to salt stress detected by photosynthesis performance. Moreover, the salt-tolerant rice varieties showed lower expression of this gene than the susceptible rice varieties under salt stress conditions. The study concludes that by acting as a negative regulator, OsCRN plays an important role in salt tolerance in rice.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Oryza/crescimento & desenvolvimento , Locos de Características Quantitativas , Tolerância ao Sal , Mapeamento Cromossômico , Regulação da Expressão Gênica de Plantas , Mutação , Oryza/genética , Fenótipo , Fotossíntese , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , Plântula/genética , Plântula/crescimento & desenvolvimento
19.
Sci Rep ; 12(1): 1203, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35075121

RESUMO

The harvested plant products, specifically, the grains of cereals are major drivers of soil phosphorus (P) depletion. However, the breeding or biotechnology efforts to develop low P seeds have not been attempted because of possible adverse effects on seedling vigour and crop establishment. Several studies have contradictory observations on influence of seed P on seedling vigour. Lack of appropriate genetic material has been the major bottleneck in reaching the consensus. In this study, we used 30 EMS induced mutants of rice cultivar Nagina22 to understand the role of seed P on seedling vigour and associated physiological processes. Seedling vigour, morpho-physiological characteristics, acid phosphatases, alpha-amylase, and expression of P transporter genes were analyzed in seedlings obtained from seeds of high and low grain P mutants. The study suggests that seed P has a significant role on seedling vigour, chlorophyll content and photosynthesis process of young seedlings, and P transport from roots. Notably, we identified few mutants such as NH4791, NH4785, NH4714, NH4663, NH4614, and NH4618 which showed least influence of low seed P on seedling vigour and other metabolic processes. Therefore, these mutants can be used in breeding programs aiming for development of low P grains. Also, these and other identified mutants can be used to decipher the genetic and molecular mechanisms regulating the differential response of seed P on germination, seedling vigour and several other physiological processes influencing the crop growth and establishment.


Assuntos
Oryza/metabolismo , Fósforo/metabolismo , Plântula/crescimento & desenvolvimento , Sementes/metabolismo , Fosfatase Ácida/metabolismo , Clorofila/metabolismo , Mutagênese , Oryza/genética , Oryza/crescimento & desenvolvimento , alfa-Amilases/metabolismo
20.
Nat Commun ; 13(1): 485, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079011

RESUMO

Nitrogen (N), one of the most important plant nutrients, plays crucial roles in multiple plant developmental processes. Spikelets are the primary sink tissues during reproductive growth, and N deficiency can cause floral abortion. However, the roles of N nutrition in meiosis, the crucial step in plant sexual reproduction, are poorly understood. Here, we identified an N-dependent meiotic entrance mutant with loss of function of ELECTRON TRANSFER FLAVOPROTEIN SUBUNIT ß (ETFß) in rice (Oryza sativa). etfß displayed meiosis initiation defects, excessive accumulation of branched-chain amino acids (BCAAs) and decrease in total N contents in spikelets under N starvation, which were rescued by applying excess exogenous inorganic N. Under N starvation, ETFß, through its involvement in BCAA catabolism, promotes N reutilization and contributes to meeting N demands of spikelets, highlighting the impact of N nutrition on meiosis initiation. We conclude that N nutrition contributes to plant fertility by affecting meiosis initiation.


Assuntos
Aminoácidos de Cadeia Ramificada/metabolismo , Flavoproteínas Transferidoras de Elétrons/metabolismo , Regulação da Expressão Gênica de Plantas , Meiose , Nitrogênio/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Flavoproteínas Transferidoras de Elétrons/genética , Fertilidade , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética
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