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1.
Plant Mol Biol ; 101(1-2): 81-93, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201686

RESUMO

KEY MESSAGE: Here we show that accumulation of galactose-containing lipids in plastid membranes in shoots and the other membranes in roots maintains Arabidopsis growth under acidic stress and acidic phosphate deficiency. Soil acidification and phosphate deficiency are closely related to each other in natural environments. In addition to the toxicity of high proton concentrations, acid soil can lead to imbalances of ion availability and nutritional deficiencies, including inorganic phosphate (Pi). Among plants, activation of non-phosphorus-containing galactolipid, digalactosyldiacylglycerol (DGDG), synthesis concomitant with phospholipid degradation, namely membrane lipid remodeling, is crucial for coping with Pi starvation. However, regulation mechanisms of membrane lipid composition during acidic stress have not been clarified. Here, we investigated lipid metabolism in Arabidopsis thaliana grown under acidic stress with or without Pi. Under Pi-sufficient acidic conditions, DGDG was increased in shoot membranes, and some Pi starvation-responsive genes that are involved in lipid remodeling were upregulated without reducing Pi content in leaves. In contrast, under acidic Pi deficiency, membrane lipid remodeling in roots was partially repressed at a lower external pH. Nevertheless, phenotypic comparison between wild type and the double mutant of MGD2/3, which are responsible for DGDG accumulation during Pi starvation, indicated that the complete absence of lipid remodeling in roots resulted in a loss of tolerance to Pi deficiency rather specifically under acidic conditions. This result suggested important physiological roles of galactolipid-enriched membranes under acidic Pi deficiency.


Assuntos
Arabidopsis/fisiologia , Galactolipídeos/metabolismo , Metabolismo dos Lipídeos , Lipídeos de Membrana/metabolismo , Fosfatos/deficiência , Fosfolipídeos/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Concentração de Íons de Hidrogênio , Fenótipo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Brotos de Planta/genética , Brotos de Planta/fisiologia , Plastídeos/metabolismo , Estresse Fisiológico
2.
Int J Mol Sci ; 20(9)2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31035580

RESUMO

In vitro plant regeneration addresses basic questions of molecular reprogramming in the absence of embryonic positional cues. The process is highly dependent on the genotype and explant characteristics. However, the regulatory mechanisms operating during organ differentiation from in vitro cultures remain largely unknown. Recently, miRNAs have emerged as key regulators during embryogenic callus induction, plant differentiation, auxin responses and totipotency. Here, we explored how development-related miRNA switches the impact on their target regulation depending on physiological and molecular events taking place during maize Tuxpeño VS-535 in vitro plant regeneration. Three callus types with distinctive regeneration potential were characterized by microscopy and histological preparations. The embryogenic calli (EC) showed higher miRNA levels than non-embryogenic tissues (NEC). An inverse correlation for miR160 and miR166 targets was found during EC callus induction, whereas miR156, miR164 and miR394 displayed similar to their targets RNA accumulation levels. Most miRNA accumulation switches took place early at regenerative spots coincident with shoot apical meristem (SAM) establishment, whereas miR156, miR160 and miR166 increased at further differentiation stages. Our data uncover particular miRNA-mediated regulation operating for maize embryogenic tissues, supporting their regulatory role in early SAM establishment and basipetala growth during the in vitro regeneration process.


Assuntos
Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Interferência de RNA , Regeneração/genética , Zea mays/genética , Zea mays/metabolismo , Especificidade de Órgãos/genética , Fenótipo , Desenvolvimento Vegetal/genética , Brotos de Planta/genética , Brotos de Planta/metabolismo
3.
Planta ; 250(2): 667-674, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31104129

RESUMO

MAIN CONCLUSION: Mercury accumulation in Arabidopsis shoots is accelerated by endodermis specific expression of fusion proteins of a bacterial mercury transporter MerC and a plant SNARE SYP121 under control of SCARECROW promoter. We previously demonstrated that the CaMV 35S RNA promoter (p35S)-driven ubiquitous expression of a bacterial mercury transporter MerC, fused with SYP121, an Arabidopsis SNARE protein increases mercury accumulation of Arabidopsis. To establish an improved fine-tuned mercury transport system in plants for phytoremediation, the present study generated and characterized transgenic Arabidopsis plants expressing MerC-SYP121 specifically in the root endodermis, which is a crucial cell type for root element uptake. We generated four independent transgenic Arabidopsis lines expressing a transgene encoding mCherry-MerC-SYP121 under the control of the endodermis-specific SCARECROW promoter (hereafter pSCR lines). Quantitative real-time PCR analysis showed that expression levels of the transgene in roots of the pSCR lines were 3-23% of the p35S driven-overexpressing line. Confocal microscopy analysis showed that mCherry-MerC-SYP121 was dominantly expressed in the endodermis of the meristematic zone as well as in the mature zone of the pSCR roots. Mercury accumulation in shoots of the pSCR lines exposed to inorganic mercury was overall higher than the wild-type and comparable to the p35S over-expressing line. These results suggest that endodermis-specific expression of the MerC-SYP121 fusion proteins in plant roots sufficiently enhances mercury uptake and accumulation into shoots, which would be an ideal phenotype for phytoremediation of mercury-contaminated environments.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Mercúrio/metabolismo , Proteínas Qa-SNARE/metabolismo , Arabidopsis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Transporte Biológico , Proteínas de Transporte de Cátions/genética , Meristema/genética , Meristema/metabolismo , Especificidade de Órgãos , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Proteínas Qa-SNARE/genética , Proteínas Recombinantes de Fusão
4.
Planta ; 250(2): 549-561, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31119363

RESUMO

MAIN CONCLUSION: OsHAK16 mediates K uptake and root-to-shoot translocation in a broad range of external K concentrations, thereby contributing to the maintenance of K homeostasis and salt tolerance in the rice shoot. The HAK/KUP/KT transporters have been widely associated with potassium (K) transport across membranes in both microbes and plants. Here, we report the physiological function of OsHAK16, a member belonging to the HAK/KUP/KT family in rice (Oryza sativa L.). Transcriptional expression of OsHAK16 was up-regulated by K deficiency or salt stress. OsHAK16 is localized at the plasma membrane. OsHAK16 knockout (KO) dramatically reduced root K net uptake rate and growth at both 0.1 mM and 1 mM K supplies, while OsHAK16 overexpression (OX) increased total K uptake and growth only at 0.1 mM K level. OsHAK16-KO decreased the rate of rubidium (Rb) uptake and translocation compared to WT at both 0.2 mM and 1 mM Rb levels. OsHAK16 disruption decreased while its overexpression increased K concentration in root slightly but in shoot remarkably. The relative distribution of total K between shoot and root decreased by 30% in OsHAK16-KO lines and increased by 30% in its OX lines compared to WT. OsHAK16-KO diminished K uptake and K/Na ratio, while OsHAK16-OX improved K uptake and translocation from root to shoot, resulting in increased sensitivity and tolerance to salt stress, respectively. Expression of OsHAK16 enhanced the growth of high salt-sensitive yeast mutant by increasing its K but no Na content. Taking all these together, we conclude that OsHAK16 plays crucial roles in maintaining K homeostasis and salt tolerance in rice shoot.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Potássio/metabolismo , Tolerância ao Sal , Proteínas de Transporte de Cátions/genética , Homeostase , Transporte de Íons , Oryza/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Brotos de Planta/genética , Brotos de Planta/fisiologia , Plantas Geneticamente Modificadas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia
5.
BMC Res Notes ; 12(1): 243, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036050

RESUMO

OBJECTIVE: Conifer genomes show high genetic diversity in intergenic regions that contain diverse sets of transposable elements with dominating long terminal repeat (LTR) retrotransposons (RE). Transcription of RE in response to environmental stimuli could produce various types of regulatory non-coding RNAs, but global genomic methylation changes could result in a coincidental expression of normally silent genomic regions. Expression of several RE families was evaluated in Scots pine seedlings after controlled inoculations with two fungal species that exhibit different modes of pathogenicity (necrotrophic and likely biotrophic); data compared to the overall RE distribution in genome. Recognition of regulatory non-coding RNA involved in host-pathogen interplay could be valuable in understanding defence mechanisms of perennial plants. RESULTS: In the case of necrotrophic fungi Heterobasidion annosum (HA), short activation followed by restriction of RE expression was revealed after inoculation and during the spread of the pathogen. After inoculation with Lophodermium seditiosum (LS), an early increase in RE expression was revealed with the spread of the pathogen and subsequent transcription rise in all seedlings. Our observations indicate that in the complex plant genome multiple RE families constitutively express in response to pathogen invasion and these sequences could undergo regulation related to host response or pathogen influence.


Assuntos
Regulação da Expressão Gênica de Plantas/imunologia , Genoma de Planta , Pinus sylvestris/genética , Doenças das Plantas/genética , Retroelementos/imunologia , Plântula/genética , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , Basidiomycota/genética , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/patogenicidade , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Pinus sylvestris/imunologia , Pinus sylvestris/microbiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Raízes de Plantas/genética , Raízes de Plantas/imunologia , Raízes de Plantas/microbiologia , Brotos de Planta/genética , Brotos de Planta/imunologia , Brotos de Planta/microbiologia , Plântula/imunologia , Plântula/microbiologia , Sequências Repetidas Terminais , Transcrição Genética
6.
BMC Plant Biol ; 19(1): 216, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31122195

RESUMO

BACKGROUND: Adaptation to drought-prone environments requires robust root architecture. Genotypes with a more vigorous root system have the potential to better adapt to soils with limited moisture content. However, root architecture is complex at both, phenotypic and genetic level. Customized mapping panels in combination with efficient screenings methods can resolve the underlying genetic factors of root traits. RESULTS: A mapping panel of 233 spring barley genotypes was evaluated for root and shoot architecture traits under non-stress and osmotic stress. A genome-wide association study elucidated 65 involved genomic regions. Among them were 34 root-specific loci, eleven hotspots with associations to up to eight traits and twelve stress-specific loci. A list of candidate genes was established based on educated guess. Selected genes were tested for associated polymorphisms. By this, 14 genes were identified as promising candidates, ten remained suggestive and 15 were rejected. The data support the important role of flowering time genes, including HvPpd-H1, HvCry2, HvCO4 and HvPRR73. Moreover, seven root-related genes, HERK2, HvARF04, HvEXPB1, PIN5, PIN7, PME5 and WOX5 are confirmed as promising candidates. For the QTL with the highest allelic effect for root thickness and plant biomass a homologue of the Arabidopsis Trx-m3 was revealed as the most promising candidate. CONCLUSIONS: This study provides a catalogue of hotspots for seedling growth, root and stress-specific genomic regions along with candidate genes for future potential incorporation in breeding attempts for enhanced yield potential, particularly in drought-prone environments. Root architecture is under polygenic control. The co-localization of well-known major genes for barley development and flowering time with QTL hotspots highlights their importance for seedling growth. Association analysis revealed the involvement of HvPpd-H1 in the development of the root system. The co-localization of root QTL with HERK2, HvARF04, HvEXPB1, PIN5, PIN7, PME5 and WOX5 represents a starting point to explore the roles of these genes in barley. Accordingly, the genes HvHOX2, HsfA2b, HvHAK2, and Dhn9, known to be involved in abiotic stress response, were located within stress-specific QTL regions and await future validation.


Assuntos
Secas , Genes de Plantas/fisiologia , Genoma de Planta/genética , Hordeum/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Genótipo , Hordeum/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Plântula/genética , Plântula/crescimento & desenvolvimento
7.
Plant Physiol Biochem ; 141: 20-29, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31125808

RESUMO

Soil salinity is one of the most abiotic stress factors that severely affects the growth and development of many plants, which can ultimately threaten crop yield. Arbuscular mycorrhiza fungi (AMF) has been proven to be effective in mitigating salinity stress by symbiosis in many crops. Asparagus officinalis are perennial plants grown in saline-alkaline soil, however, limited information on their molecular mechanisms has restricted efficient application of AMF to garden asparagus under salinity stress. In this study, we conducted a transcriptome analysis on the leaves of garden asparagus to identify gene expression under salinity stress. Seedlings were grown in 4 treatments, including non-inoculated AMF using distilled water (NI), inoculated AMF using distilled water (AMF), non-inoculated with salinity stress (NI + S), and inoculated with salinity stress (AMF + S). A total of 6019 novel genes were obtained based on the reference-guided assembly of the garden asparagus transcriptome. Results revealed that 455 differentially expressed genes (DEGs) were identified when comparing NI + S to AMF + S. However, among the up-regulated DEGs, 41 DEGs were down-regulated, while 242 DEGs had no differences in their expression levels when comparing NI to NI + S. These DEGs' expression patterns may be key induced by AMF under salinity stress. Additionally, the GO and KEGG enrichment analyses of 455 DEGs revealed that these genes mainly participate in the improvement of the internal environment in plant cells, nitrogen metabolic-related processes, and possible photoprotection mechanisms. These findings provide insight into enhanced salinity stress adaptation by AMF inoculation, as well as salt-tolerant candidate genes for further functional analyses.


Assuntos
Asparagus (Planta)/genética , Micorrizas/fisiologia , Estresse Salino , Transcriptoma , Asparagus (Planta)/microbiologia , DNA Complementar/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Genoma de Planta , Metabolômica , Nitrogênio/química , Fotoquímica , Folhas de Planta/genética , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Brotos de Planta/genética , Salinidade , Tolerância ao Sal , Sais/química , Plântula , Análise de Sequência de RNA , Simbiose
8.
Plant Mol Biol ; 100(4-5): 467-479, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31004275

RESUMO

KEY MESSAGE: We have isolated several Osiaa23 rice mutants with different knockout genotypes, resulting in different phenotypes, which suggested that different genetic backgrounds or mutation types influence gene function. The Auxin/Indole-3-Acetic Acid (Aux/IAA) gene family performs critical roles in auxin signal transduction in plants. In rice, the gene OsIAA23 (Os06t0597000) is known to affect development of roots and shoots, but previous knockouts in OsIAA23 have been sterile and difficult for research continuously. Here, we isolate new Osiaa23 mutants using the CRISPR/Cas9 system in japonica (Wuyunjing24) and indica (Kasalath) rice, with extensive genome re-sequencing to confirm the absence of off-target effects. In Kasalath, mutants with a 13-amino acid deletion showed profoundly greater dwarfing, lateral root developmental disorder, and fertility deficiency, relative to mutants with a single amino acid deletion, demonstrating that those 13 amino acids in Kasalath are essential to gene function. In Wuyunjing24, we predicted that mutants with a single base-pair frameshift insertion would experience premature termination and strong phenotypic defects, but instead these lines exhibited negligible phenotypic difference and normal fertility. Through RNA-seq, we show here that new mosaic transcripts of OsIAA23 were produced de novo, which circumvented the premature termination and thereby preserved the wild-type phenotype. This finding is a notable demonstration in plants that mutants can mask loss of function CRISPR/Cas9 editing of the target gene through de novo changes in alternative splicing.


Assuntos
Ácidos Indolacéticos/metabolismo , Oryza/genética , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Sistemas CRISPR-Cas , Técnicas de Inativação de Genes , Genoma de Planta , Genótipo , Mutação , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fenótipo , Desenvolvimento Vegetal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Mol Biotechnol ; 61(6): 442-450, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980224

RESUMO

Soil salinity imposes a serious threat to the productivity of agricultural crops. Among several other transporters, high-affinity K+ transporter (HKT)'s play an important role in reducing the phytotoxicity of Na+. Expression of Eutrema salsugineum (a halophyte) HKT1;2 is induced upon salt exposure. To elucidate the role of its promoter, we compared the sequences of HKT1;2 promoters from E. salsugineum (1822 bp) and E. botschantzevii (1811 bp) with Arabidopsis thaliana HKT1;1 (846 bp) promoter. In silico analysis predicted several cis-acting regulatory elements (GT-1 elements, core motifs of DRE/CRT, MYC/MYB-recognition sites and ACGT elements). Activities of the three promoters were analyzed by measuring HKT1;1 and/or HKT1;2 transcript level in the Athkt1;1 mutant plants. NaCl tolerance of the transgenics was also assessed. Our results depicted that expressing either AtHKT1;1 or EsHKT1;2 coding regions under the control of AtHKT1;1 promoter, almost reversed the hypersensitivity of the mutant for salt, on contrarily, when AtHKT1;1 coding sequence expressed under either Es or EbHKT1;2 promoters did not. Changes in shoot Na+/K+ concentrations under salt exposure is significantly consistent with the complementation ability of the mutant. The transcript concentration for genes under the control of either of Eutrema promoters, at control level was very less. This may suggest that either an important upstream response motif is missed or that A. thaliana misses a transcriptional regulator that is essential for salt-inducible HKT1 expression in Eutrema.


Assuntos
Arabidopsis/genética , Brassicaceae/genética , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Tolerância ao Sal/genética , Simportadores/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Sequência de Bases , Brassicaceae/efeitos dos fármacos , Brassicaceae/crescimento & desenvolvimento , Brassicaceae/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Teste de Complementação Genética , Transporte de Íons/efeitos dos fármacos , Mutação , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Potássio/metabolismo , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Sódio/metabolismo , Cloreto de Sódio/farmacologia , Especificidade da Espécie , Estresse Fisiológico/genética , Simportadores/metabolismo
10.
PLoS Genet ; 15(4): e1008065, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30946745

RESUMO

Integration of environmental and endogenous cues at plant shoot meristems determines the timing of flowering and reproductive development. The MADS box transcription factor FLOWERING LOCUS C (FLC) of Arabidopsis thaliana is an important repressor of floral transition, which blocks flowering until plants are exposed to winter cold. However, the target genes of FLC have not been thoroughly described, and our understanding of the mechanisms by which FLC represses transcription of these targets and how this repression is overcome during floral transition is still fragmentary. Here, we identify and characterize TARGET OF FLC AND SVP1 (TFS1), a novel target gene of FLC and its interacting protein SHORT VEGETATIVE PHASE (SVP). TFS1 encodes a B3-type transcription factor, and we show that tfs1 mutants are later flowering than wild-type, particularly under short days. FLC and SVP repress TFS1 transcription leading to deposition of trimethylation of Iysine 27 of histone 3 (H3K27me3) by the Polycomb Repressive Complex 2 at the TFS1 locus. During floral transition, after downregulation of FLC by cold, TFS1 transcription is promoted by SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1), a MADS box protein encoded by another target of FLC/SVP. SOC1 opposes PRC function at TFS1 through recruitment of the histone demethylase RELATIVE OF EARLY FLOWERING 6 (REF6) and the SWI/SNF chromatin remodeler ATPase BRAHMA (BRM). This recruitment of BRM is also strictly required for SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 9 (SPL9) binding at TFS1 to coordinate RNAPII recruitment through the Mediator complex. Thus, we show that antagonistic chromatin modifications mediated by different MADS box transcription factor complexes play a crucial role in defining the temporal and spatial patterns of transcription of genes within a network of interactions downstream of FLC/SVP during floral transition.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Proteínas de Domínio MADS/genética , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Cromatina/genética , Cromatina/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Código das Histonas/genética , Proteínas de Domínio MADS/metabolismo , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Modelos Biológicos , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
PLoS Genet ; 15(4): e1007954, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31009456

RESUMO

One of the main outcomes of quantitative genetics approaches to natural variation is to reveal the genetic architecture underlying the phenotypic space. Complex genetic architectures are described as including numerous loci (or alleles) with small-effect and/or low-frequency in the populations, interactions with the genetic background, environment or age. Linkage or association mapping strategies will be more or less sensitive to this complexity, so that we still have an unclear picture of its extent. By combining high-throughput phenotyping under two environmental conditions with classical QTL mapping approaches in multiple Arabidopsis thaliana segregating populations as well as advanced near isogenic lines construction and survey, we have attempted to improve our understanding of quantitative phenotypic variation. Integrative traits such as those related to vegetative growth used in this work (highlighting either cumulative growth, growth rate or morphology) all showed complex and dynamic genetic architecture with respect to the segregating population and condition. The more resolutive our mapping approach, the more complexity we uncover, with several instances of QTLs visible in near isogenic lines but not detected with the initial QTL mapping, indicating that our phenotyping accuracy was less limiting than the mapping resolution with respect to the underlying genetic architecture. In an ultimate approach to resolve this complexity, we intensified our phenotyping effort to target specifically a 3Mb-region known to segregate for a major quantitative trait gene, using a series of selected lines recombined every 100kb. We discovered that at least 3 other independent QTLs had remained hidden in this region, some with trait- or condition-specific effects, or opposite allelic effects. If we were to extrapolate the figures obtained on this specific region in this particular cross to the genome- and species-scale, we would predict hundreds of causative loci of detectable phenotypic effect controlling these growth-related phenotypes.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Mapeamento Cromossômico , Cruzamentos Genéticos , Epistasia Genética , Variação Genética , Genoma de Planta , Endogamia , Herança Multifatorial , Fenótipo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Locos de Características Quantitativas , Recombinação Genética
12.
Planta ; 250(1): 41-57, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30904943

RESUMO

MAIN CONCLUSION: The plasticity of plant growth response to differing nitrate availability renders the identification of biomarkers difficult, but allows access to genetic factors as tools to modulate root systems to a wide range of soil conditions. Nitrogen availability is a major determinant of crop yield. While the application of fertiliser substantially increases the yield on poor soils, it also causes nitrate pollution of water resources and high costs for farmers. Increasing nitrogen use efficiency in crop plants is a necessary step to implement low-input agricultural systems. We exploited the genetic diversity present in the worldwide Arabidopsis thaliana population to study adaptive growth patterns and changes in gene expression associated with chronic low nitrate stress, to identify biomarkers associated with good plant performance under low nitrate availability. Arabidopsis accessions were grown on agar plates with limited and sufficient supply of nitrate to measure root system architecture as well as shoot and root fresh weight. Differential gene expression was determined using Affymetrix ATH1 arrays. We show that the response to differing nitrate availability is highly variable in Arabidopsis accessions. Analyses of vegetative shoot growth and root system architecture identified accession-specific reaction modes to cope with limited nitrate availability. Transcription and epigenetic factors were identified as important players in the adaption to limited nitrogen in a global gene expression analysis. Five nitrate-responsive genes emerged as possible biomarkers for NUE in Arabidopsis. The plasticity of plant growth in response to differing nitrate availability in the substrate renders the identification of morphological and molecular features as biomarkers difficult, but at the same time allows access to a multitude of genetic factors which can be used as tools to modulate and adjust root systems to a wide range of soil conditions.


Assuntos
Arabidopsis/genética , Variação Genética , Nitratos/metabolismo , Nitrogênio/metabolismo , Adaptação Fisiológica , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Brotos de Planta/genética , Brotos de Planta/fisiologia , Solo/química
13.
Planta ; 250(1): 105-114, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30927053

RESUMO

MAIN CONCLUSION: Rice phytochrome-interacting factor-like protein OsPIL15 regulates tiller angle through light and gravity signals in rice. Tiller angle of cereal crops is a key agronomic trait that contributes to grain production. An understanding of how tiller angle is controlled is helpful for achieving ideal plant architecture to improve grain yield. Phytochrome-interacting factors (PIFs) are known to regulate seed germination, seedling skotomorphogenesis, shade avoidance, and flowering in Arabidopsis thaliana. Here, we report that OsPIL15 is, indeed, a rice PIF that negatively regulates tiller angle. Dominant-negative OsPIL15 plants displayed a larger tiller angle, which was associated with reduced shoot gravitropism. Phytochrome B (phyB) is the main photoreceptor perceiving the low red:far-red ratio of shade light. Compared with wild-type rice plants, loss-of-function phyB plants and OsPIL15-overexpressing plants showed smaller tiller angles and enhanced shoot gravitropism. In addition, more OsPIL15 protein accumulated in phyB plants than in wild-type plants. Light regulates the level of the OsPIL15 protein negatively, depending on phyB partially. We propose that OsPIL15 integrates light and gravity signals to regulate tiller angle in rice.


Assuntos
Regulação da Expressão Gênica de Plantas , Gravitropismo/genética , Oryza/fisiologia , Fitocromo/metabolismo , Proteínas de Plantas/metabolismo , Gravitropismo/efeitos da radiação , Luz , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/efeitos da radiação , Proteínas de Plantas/genética , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Brotos de Planta/efeitos da radiação , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Plântula/efeitos da radiação
14.
Ecotoxicol Environ Saf ; 176: 85-94, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30921700

RESUMO

Brassica parachinensis L., a daily consumed leaf vegetable, is a high-Cd accumulator that substantially threatens human health. Screening and breeding Cd pollution-safe cultivars (Cd-PSCs) of crops is a low-cost strategy to restrict human Cd intake from contaminated soils via the food chain. However, little is known about the molecular mechanisms underlying the low-Cd-accumulating traits of B. parachinensis Cd-PSCs. In the current study, we analyzed the transcriptomes of the Cd-treated (5 µM) roots and shoots of a low-Cd-accumulating cultivar (SJ19) and a high-Cd-accumulating cultivar (CX4) of B. parachinensis to reveal the molecular mechanisms in response to Cd stress. Compared to CX4, many pathways involved in carbohydrate and amino acid metabolisms were exclusively up-regulated in SJ19 roots upon exposure to low Cd concentrations, which may produce more energy and metabolites for Cd detoxification. Antioxidant enzymes in the peroxisome were up-regulated in both SJ19 and CX4 roots in response to Cd, while glutathione biosynthesis was only activated in SJ19 roots. In SJ19 shoots, pathways of photosynthesis and cell growth were activated to mitigate Cd-induced damages. Furthermore, Cd transport genes, such as MTP1, HMA3 and CAX family genes, were highly induced by Cd stress in SJ19 roots in accordance with the high Cd concentration in roots, while genes involved in root-to-shoot Cd translocation such as FRD3 and CESA3 were suppressed, which may contribute to the low Cd concertation in edible part of SJ19. Our study provides a genetic basis for further Cd-PSCs screening and breeding.


Assuntos
Brassica/genética , Cádmio/metabolismo , Produtos Agrícolas/genética , Poluentes do Solo/metabolismo , Brassica/metabolismo , Cádmio/farmacologia , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Humanos , Redes e Vias Metabólicas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , Poluentes do Solo/farmacologia , Transcriptoma/efeitos dos fármacos
15.
Plant Sci ; 280: 228-240, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30824001

RESUMO

Salinity severely hampers crop productivity worldwide and plant growth promoting bacteria could serve as a sustainable solution to improve plant growth under salt stress. However, the molecular mechanisms underlying salt stress tolerance promotion by beneficial bacteria remain unclear. In this work, six bacterial isolates from four different desert plant species were screened for their biochemical plant growth promoting traits and salinity stress tolerance promotion of the unknown host plant Arabidopsis thaliana. Five of the isolates induced variable root phenotypes but could all increase plant shoot and root weight under salinity stress. Inoculation of Arabidopsis with five isolates under salinity stress resulted in tissue-specific transcriptional changes of ion transporters and reduced Na+/K+ shoot ratios. The work provides first insights into the possible mechanisms and the commonality by which phylogenetically diverse bacteria from different desert plants induce salinity stress tolerance in Arabidopsis. The bacterial isolates provide new tools for studying abiotic stress tolerance mechanisms in plants and a promising agricultural solution for increasing crop yields in semi-arid regions.


Assuntos
Arabidopsis/microbiologia , Bactérias/classificação , Fenômenos Fisiológicos Bacterianos , Regulação da Expressão Gênica de Plantas , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Clima Desértico , Endófitos , Transporte de Íons , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Filogenia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/microbiologia , Brotos de Planta/fisiologia , Potássio/análise , Estresse Salino , Tolerância ao Sal , Sódio/análise
16.
Int J Mol Sci ; 20(6)2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30875914

RESUMO

Plant-derived smoke has effects on plant growth. To find the molecular mechanism of plant-derived smoke on maize, a gel-free/label-free proteomic technique was used. The length of root and shoot were increased in maize by plant-derived smoke. Proteomic analysis revealed that 2000 ppm plant-derived smoke changed the abundance of 69 proteins in 4-days old maize shoot. Proteins in cytoplasm, chloroplast, and cell membrane were altered by plant-derived smoke. Catalytic, signaling, and nucleotide binding proteins were changed. Proteins related to sucrose synthase, nucleotides, signaling, and glutathione were significantly increased; however, cell wall, lipids, photosynthetic, and amino acid degradations related proteins were decreased. Based on proteomic and immunoblot analyses, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) was decreased; however, RuBisCO activase was not changed by plant-derived smoke in maize shoot. Ascorbate peroxidase was not affected; however, peroxiredoxin was decreased by plant-derived smoke. Furthermore, the results from enzyme-activity and mRNA-expression analyses confirmed regulation of ascorbate peroxidase and the peroxiredoxinin reactive oxygen scavenging system. These results suggest that increases in sucrose synthase, nucleotides, signaling, and glutathione related proteins combined with regulation of reactive oxygen species and their scavenging system in response to plant-derived smoke may improve maize growth.


Assuntos
Proteínas de Plantas/metabolismo , Plantas/química , Proteômica/métodos , Fumaça , Zea mays/crescimento & desenvolvimento , Ascorbato Peroxidases/genética , Ascorbato Peroxidases/metabolismo , Membrana Celular/metabolismo , Cloroplastos/metabolismo , Citoplasma/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Zea mays/efeitos dos fármacos , Zea mays/genética , Zea mays/metabolismo
17.
Mol Biol Rep ; 46(2): 2121-2129, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30762165

RESUMO

Hypericum lydium Boiss. is a perennial plant of the Hypericaceae family, which has been used in particular to treat depression. The aim of this study was to determine in vitro antioxidant, antimicrobial activities, anticholinesterase (acetylcholinesterase (AChE)/butyrylcholinesterase (BChE)), antidiabetic activities (α-glucosidase/α-amylase) and Tyrosinase inhibitor activity of methanol and water extracts of H. lydium. Also, gene expression has been evaluated in the shoot and root by microarray technology. So, in general, the purpose of this study is to study the active molecules such as antioxidant, antimicrobial, antidiabetic, enzymes and genes in the plant, which is the first to be reported. The experiments were conducted in a completely randomized design with three replications. In addition, gene expression was compared in the shoot and root parts. Expression profiling was carried out by microarrays. According to the results, the highest chemical components were determined in methanol extract rather than water extract. There was a difference between the obtained components. While the highest antioxidant activity was determined from the methanol extract of plant herbs for DPPH Free Radical Scavenging Activity, antioxidant activity was the same in both methanol and water extracts using the ABTS method. The methanol extract demonstrated stronger anticholinesterase (AChE and BChE) and α-amylase inhibition activity. This study was complemented by the detection of antioxidant activity and some enzyme inhibition activity in the methanol extract. Microarray showed 10,784 genes had significantly different expression in root and shoot. There was a positive effect of methanol extract in respect of different activities compared to the water extract. Gene expression showed that the number of expressed genes in the root was greater than the shoot.


Assuntos
Antioxidantes/isolamento & purificação , Hypericum/genética , Extratos Vegetais/isolamento & purificação , Acetilcolinesterase/metabolismo , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase , Flavonoides/farmacologia , Hypericum/metabolismo , Metanol/química , Extratos Vegetais/farmacologia , Raízes de Plantas/genética , Brotos de Planta/genética , Água/química
18.
Mol Biol Rep ; 46(2): 1909-1930, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30721422

RESUMO

Brassinosteroids (BRs) are a group of plant steroid hormones that play crucial roles in a range of plant growth and development processes. BR action includes active BR formation by a complex biosynthesis process and driving BR biological function through signal transduction. Although the characterization of several BR action-related genes has been conducted in a few model plants, systematic information about these genes in bamboo is still lacking. We identified 64 genes related to BR action from the genome of moso bamboo (Phyllostachys edulis), including twenty that participated in BR biosynthesis and forty-four involved in BR signal transduction. The characteristics of all these candidate genes were identified by bioinformatics methods, including the gene structures, basic physical and chemical properties of proteins, conserved domains and evolutionary relationships. Based on the transcriptome data, the candidate genes demonstrated different expression patterns, which were further validated by qRT-PCR using templates from bamboo shoots with different heights. Thirty-four positive and three negative co-expression modules were identified by 44 candidate genes in the newly emerging bamboo shoot. The gene expression patterns and co-expression modules of BR action-related genes in bamboo shoots indicated that they might function to promote bamboo growth through BR biosynthesis and signal transduction processes. This study provides the first step towards the cloning and functional dissection of the role of BR action-related genes in moso bamboo, which also presents an excellent opportunity for genetic engineering using the candidate genes to improve bamboo quantity and quality.


Assuntos
Brassinosteroides/biossíntese , Brassinosteroides/metabolismo , Sasa/genética , Biologia Computacional , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Estudo de Associação Genômica Ampla/métodos , Filogenia , Reguladores de Crescimento de Planta/genética , Proteínas de Plantas/genética , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Ativação Transcricional , Transcriptoma/genética
19.
Molecules ; 24(3)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717158

RESUMO

Bioactive metabolites in Codonopsis pilosula are of particular interest as an immunostimulant. Methyl jasmonate (MeJA) plays an important role in the elicitation of metabolite biosynthesis. Here, we explored the response of metabolites to MeJA elicitation in C. pilosula adventitious roots and multiple shoots. The results showed that the biomass, polysaccharide, and lobetyolin content of adventitious roots exhibited the highest increases with 100 µmol·L-1 MeJA at the 16th day of subculture, whereas the atractylenolide III (a terpenoid) content increased extremely with 50 µmol·L-1 MeJA treatment at the 7th day of subculture. In addition, the biomass and lobetyolin content significantly increased at the 4th day after treatment. Similarly, the polysaccharide and lobetyolin content increased in multiple shoots. Further identification of different metabolites responding to MeJA by ¹H-NMR showed an extremely significant increase of the lobetyolinin level, which coincided with lobetyolin. Accordingly, the precursor, fatty acids, showed a highly significant decrease in their levels. Furthermore, a significant increase in ß-d-fructose-butanol glycoside was detected, which was accompanied by a decrease in the sucrose level. Accordingly, the enzyme genes responsible for terpenoid and carbohydrate biosynthesis, CpUGPase, and CpPMK, were up regulated. In conclusion, MeJA promoted culture growth and accelerated bioactive metabolite accumulation by regulating the expression of the metabolite biosynthesis related genes, CpUGPase and CpPMK in C. pilosula.


Assuntos
Acetatos/farmacologia , Codonopsis/efeitos dos fármacos , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas , Oxilipinas/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/genética , Biomassa , Codonopsis/genética , Codonopsis/crescimento & desenvolvimento , Codonopsis/metabolismo , Ácidos Graxos/biossíntese , Lactonas/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Fosfotransferases (Aceptor do Grupo Fosfato)/genética , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Poli-Inos/metabolismo , Sesquiterpenos/metabolismo , UTP-Glucose-1-Fosfato Uridililtransferase/genética , UTP-Glucose-1-Fosfato Uridililtransferase/metabolismo
20.
BMC Plant Biol ; 19(1): 72, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30760212

RESUMO

BACKGROUND: Drought is an important constraint on grapevine sustainability. Vitis riparia, widely used in rootstock and scion breeding, has been studied in isolated leaf drying response studies; however, it is essential to identify key root and shoot water deficit signaling traits in intact plants. This information will aid improved scion and rootstock selection and management practices in grapevine. RNAseq data were generated from V. riparia roots and shoots under water deficit and well-watered conditions to determine root signaling and shoot responses to water deficit. RESULTS: Shoot elongation, photosynthetic rate, and stomatal conductance were significantly reduced in water deficit (WD) treated than in well-watered grapevines. RNAseq analysis indicated greater transcriptional differences in shoots than in roots under WD, with 6925 and 1395 genes differentially expressed, respectively (q-value < 0.05). There were 50 and 25 VitisNet pathways significantly enriched in WD relative to well-watered treatments in grapevine shoots and roots, respectively. The ABA biosynthesis genes beta-carotene hydroxylase, zeaxanthin epoxidase, and 9-cis-epoxycarotenoid dioxygenases were up-regulated in WD root and WD shoot. A positive enrichment of ABA biosynthesis genes and signaling pathways in WD grapevine roots indicated enhanced root signaling to the shoot. An increased frequency of differentially expressed reactive oxygen species scavenging (ROS) genes were found in the WD shoot. Analyses of hormone signaling genes indicated a strong ABA, auxin, and ethylene network and an ABA, cytokinin, and circadian rhythm network in both WD shoot and WD root. CONCLUSIONS: This work supports previous findings in detached leaf studies suggesting ABA-responsive binding factor 2 (ABF2) is a central regulator in ABA signaling in the WD shoot. Likewise, ABF2 may have a key role in V. riparia WD shoot and WD root. A role for ABF3 was indicated only in WD root. WD shoot and WD root hormone expression analysis identified strong ABA, auxin, ethylene, cytokinin, and circadian rhythm signaling networks. These results present the first ABA, cytokinin, and circadian rhythm signaling network in roots under water deficit. These networks point to organ specific regulators that should be explored to further define the communication network from soil to shoot.


Assuntos
Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/metabolismo , Transdução de Sinais , Transcriptoma , Vitis/genética , Ácido Abscísico/metabolismo , Citocininas/metabolismo , Desidratação , Secas , Etilenos/metabolismo , Especificidade de Órgãos , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Brotos de Planta/genética , Brotos de Planta/fisiologia , Vitis/fisiologia
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