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1.
BMC Plant Biol ; 21(1): 477, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34670492

RESUMO

BACKGROUND: Both underground rhizomes/buds and above-ground Moso bamboo (Phyllostachys heterocycla) shoots/culms/branches are connected together into a close inter-connecting system in which nutrients are transported and shared among each organ. However, the starch storage and utilization mechanisms during bamboo shoot growth remain unclear. This study aimed to reveal in which organs starch was stored, how carbohydrates were transformed among each organ, and how the expression of key genes was regulated during bamboo shoot growth and developmental stages which should lay a foundation for developing new theoretical techniques for bamboo cultivation. RESULTS: Based on changes of the NSC content, starch metabolism-related enzyme activity and gene expression from S0 to S3, we observed that starch grains were mainly elliptical in shape and proliferated through budding and constriction. Content of both soluble sugar and starch in bamboo shoot peaked at S0, in which the former decreased gradually, and the latter initially decreased and then increased as shoots grew. Starch synthesis-related enzymes (AGPase, GBSS and SBE) and starch hydrolase (α-amylase and ß-amylase) activities exhibited the same dynamic change patterns as those of the starch content. From S0 to S3, the activity of starch synthesis-related enzyme and starch amylase in bamboo rhizome was significantly higher than that in bamboo shoot, while the NSC content in rhizomes was obviously lower than that in bamboo shoots. It was revealed by the comparative transcriptome analysis that the expression of starch synthesis-related enzyme-encoding genes were increased at S0, but reduced thereafter, with almost the same dynamic change tendency as the starch content and metabolism-related enzymes, especially during S0 and S1. It was revealed by the gene interaction analysis that AGPase and SBE were core genes for the starch and sucrose metabolism pathway. CONCLUSIONS: Bamboo shoots were the main organ in which starch was stored, while bamboo rhizome should be mainly functioned as a carbohydrate transportation channel and the second carbohydrate sink. Starch metabolism-related genes were expressed at the transcriptional level during underground growth, but at the post-transcriptional level during above-ground growth. It may be possible to enhance edible bamboo shoot quality for an alternative starch source through genetic engineering.


Assuntos
Metabolismo dos Carboidratos/genética , Proteínas de Plantas/metabolismo , Poaceae/genética , Amido/metabolismo , Transcriptoma , Enzima Ramificadora de 1,4-alfa-Glucana/genética , Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Amilases/genética , Amilases/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Brotos de Planta/ultraestrutura , Poaceae/crescimento & desenvolvimento , Poaceae/fisiologia , Poaceae/ultraestrutura , Rizoma/genética , Rizoma/crescimento & desenvolvimento , Rizoma/fisiologia , Rizoma/ultraestrutura
2.
Plant Sci ; 312: 111035, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34620439

RESUMO

After germination, the maize shoot proceeds through a series of developmental stages before flowering. The first transition occurs during the vegetative phase where the shoot matures from the juvenile to the adult phase, called vegetative phase change (VPC). In maize, both phases exhibit easily-scored morphological characteristics, facilitating the elucidation of molecular mechanisms directing the characteristic gene expression patterns and resulting physiological features of each phase. miR156 expression is high during the juvenile phase, suppressing expression of squamosa promoter binding proteins/SBP-like transcription factors and miR172. The decline in miR156 and subsequent increase in miR172 expression marks the transition into the adult phase, where miR172 represses transcripts that confer juvenile traits. Leaf-derived signals attenuate miR156 expression and thus the duration of the juvenile phase. As found in other species, VPC in maize utilizes signals that consist of hormones, stress, and sugar to direct epigenetic modifiers. In this review we identify the intersection of leaf-derived signaling with components that contribute to the epigenetic changes which may, in turn, manage the distinct global gene expression patterns of each phase. In maize, published research regarding chromatin remodeling during VPC is minimal. Therefore, we identified epigenetic regulators in the maize genome and, using published gene expression data and research from other plant species, identify VPC candidates.


Assuntos
Epigênese Genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/genética , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , MicroRNAs/fisiologia , Plantas Geneticamente Modificadas , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
3.
Int J Mol Sci ; 22(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502220

RESUMO

Phosphorus (P) is an essential macronutrient, playing a role in developmental and metabolic processes in plants. To understand the local and systemic responses of sorghum to inorganic phosphorus (Pi) starvation and the potential of straw and ash for reutilisation in agriculture, we compared two grain (Razinieh) and sweet (Della) sorghum varieties with respect to their morpho-physiological and molecular responses. We found that Pi starvation increased the elongation of primary roots, the formation of lateral roots, and the accumulation of anthocyanin. In Razinieh, lateral roots were promoted to a higher extent, correlated with a higher expression of SbPht1 phosphate transporters. Infrared spectra of straw from mature plants raised to maturity showed two prominent bands at 1371 and 2337 cm-1, which could be assigned to P-H(H2) stretching vibration in phosphine acid and phosphinothious acid, and their derivates, whose abundance correlated with phosphate uptake of the source plant and genotype (with a higher intensity in Razinieh). The ash generated from these straws stimulated the shoot elongation and root development of the rice seedlings, especially for the material derived from Razinieh raised under Pi starvation. In conclusion, sorghum growing on marginal lands has potential as a bio-economy alternative for mineral phosphorus recycling.


Assuntos
Oryza/crescimento & desenvolvimento , Fósforo/metabolismo , Desenvolvimento Vegetal , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Sorghum/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Sorghum/química , Estresse Fisiológico
4.
PLoS One ; 16(9): e0257172, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34492083

RESUMO

As an essential element, zinc (Zn) can improve or inhibit the growth of plants depending on its concentrations. In this study, the effects of 24-Epibrassinolide (EBR), one well-known steroid phytohormone regulating plant growth and alleviating abiotic stress damage, on morphological parameters and antioxidant capacities of Sedum lineare were investigated under different Zn doses. Compared to plants only exposed to Zn, simultaneously foliar application of 0.75 µM EBR significantly improved multiple morphological characteristics and such growth-improving effects were more significant at high Zn concentrations. At a detrimental 800 µM Zn, EBR benefitted plant growth most prominently, as shown by that the stem length, fresh weight and internode length were increased by 111%, 85% and 157%, respectively; than Zn solely treated plants. EBR spray also enhanced both the activities of antioxidant enzymes such as peroxidase (POD), ascorbate peroxidase (APX), glutathione reductase (GR), and the contents of antioxidative agents including ascorbic acid (AsA) and glutathione (GSH), which in turn decreased the accumulation of reactive oxygen species (ROS) and alleviated the lipid peroxidation in plants. Thus, by demonstrating that EBR could help S. lineare resist high-zinc stress through strengthening the antioxidant system, this work provided a new idea for expanding the planting range of Crassulaceae plants in heavy metal contaminated soil for phytoremediation purpose in the future.


Assuntos
Antioxidantes/farmacologia , Brassinosteroides/farmacologia , Sedum/crescimento & desenvolvimento , Esteroides Heterocíclicos/farmacologia , Estresse Fisiológico , Zinco/toxicidade , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/enzimologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Sedum/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Superóxidos/metabolismo
5.
Molecules ; 26(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361814

RESUMO

The study demonstrated the effects of precursor feeding on the production of glucosinolates (GSLs), flavonoids, polyphenols, saccharides, and photosynthetic pigments in Nasturtium officinale microshoot cultures grown in Plantform bioreactors. It also evaluated the antioxidant and antimicrobial activities of extracts. L-phenylalanine (Phe) and L-tryptophan (Trp) as precursors were tested at 0.05, 0.1, 0.5, 1.0, and 3.0 mM. They were added at the beginning (day 0) or on day 10 of the culture. Microshoots were harvested after 20 days. Microshoots treated with 3.0 mM Phe (day 0) had the highest total GSL content (269.20 mg/100 g DW). The qualitative and quantitative profiles of the GSLs (UHPLC-DAD-MS/MS) were influenced by precursor feeding. Phe at 3.0 mM stimulated the best production of 4-methoxyglucobrassicin (149.99 mg/100 g DW) and gluconasturtiin (36.17 mg/100 g DW). Total flavonoids increased to a maximum of 1364.38 mg/100 g DW with 3.0 mM Phe (day 0), and polyphenols to a maximum of 1062.76 mg/100 g DW with 3.0 mM Trp (day 0). The precursors also increased the amounts of p-coumaric and ferulic acids, and rutoside, and generally increased the production of active photosynthetic pigments. Antioxidant potential increased the most with 0.1 mM Phe (day 0) (CUPRAC, FRAP), and with 0.5 mM Trp (day 10) (DPPH). The extracts of microshoots treated with 3.0 mM Phe (day 0) showed the most promising bacteriostatic activity against microaerobic Gram-positive acne strains (MIC 250-500 µg/mL, 20-21 mm inhibition zones). No extract was cytotoxic to normal human fibroblasts over the tested concentration range (up to 250 µg/mL).


Assuntos
Antioxidantes/química , Nasturtium/química , Extratos Vegetais/química , Brotos de Planta/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Biomassa , Reatores Biológicos , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Humanos , Nasturtium/metabolismo , Extratos Vegetais/farmacologia , Brotos de Planta/crescimento & desenvolvimento , Schisandra/química , Espectrometria de Massas em Tandem
6.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361755

RESUMO

Zinc (Zn) is an essential micronutrient for plant growth, and Zn deficiency is a global issue, especially in tropical soils. This study aimed to investigate the effects of humic acid (HA) and the Zn addition (Zn sulfate + HA) on the growth of maize and brachiaria in two contrasting Oxisols. The potential complexation of Zn sulfate by HA was evaluated by Fourier-transform infrared (FTIR) spectroscopy analysis. Zinc content and its availability in solution and the shoot and root biomass of maize and brachiaria were determined. FTIR spectroscopy revealed the complexation of Zn sulfate by HA through its S and C functional groups. In both Oxisols, solution Zn increased due to the combined use of Zn and HA. In a soil type-dependent manner, maize biomass and Zn in its shoots were affected only by the exclusive use of Zn fertilization. In the Yellow Oxisol, brachiaria growth and Zn accumulated in its shoot were positively affected by the combined use of Zn fertilization with HA. In the Oxisol with lower organic matter content, HA can assure adequate supplying of residual Zn, while increasing growth of brachiaria cultivated in sequence to maize.


Assuntos
Brachiaria/efeitos dos fármacos , Substâncias Húmicas/análise , Solo/química , Zea mays/efeitos dos fármacos , Sulfato de Zinco/farmacologia , Brachiaria/crescimento & desenvolvimento , Brasil , Fertilizantes/análise , Concentração de Íons de Hidrogênio , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier , Zea mays/crescimento & desenvolvimento , Sulfato de Zinco/análise , Sulfato de Zinco/química
7.
Nat Plants ; 7(9): 1276-1287, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34354259

RESUMO

Stem cell populations in all multicellular organisms are situated in a niche, which is a special microenvironment that defines stem cell fate. The interplay between stem cells and their niches is crucial for stem cell maintenance. Here, we show that an endogenous stress-related signal (ESS) is overrepresented in the shoot stem cell niche under natural growth conditions, and the vast majority of known stem-cell-specific and niche-specific genes responded to stress signals. Interference with the ESS in the stem cell niche by blocking ethylene signalling impaired stem cell maintenance. Ethylene-insensitive 3 (EIN3), the key transcription factor in ethylene signalling, directly actives the expression of the stress hub transcription factor AGAMOUS-LIKE 22 (AGL22) in the stem cell niche and relays ESS signals to the WUSCHEL/CLAVATA network. Our results provide a mechanistic framework for ESS signalling control of the stem cell niche and demonstrate that plant stem cells are maintained by a native stress microenvironment in vivo.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Diferenciação Celular/genética , Meristema/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/genética , Receptores de Superfície Celular/genética , Arabidopsis/genética , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Meristema/genética , Transdução de Sinais , Estresse Fisiológico
8.
PLoS One ; 16(8): e0235525, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34388148

RESUMO

Cannabis sativa is relatively recalcitrant to de novo regeneration, but several studies have reported shoot organogenesis or somatic embryogenesis from non-meristematic tissues. Most report infrequent regeneration rates from these tissues, but a landmark publication from 2010 achieved regeneration from leaf explants with a 96% response rate, producing an average of 12.3 shoots per explant in a single drug-type accession. Despite the importance regeneration plays in plant biotechnology and the renewed interest in this crop the aforementioned protocol has not been used in subsequent papers in the decade since it was published, raising concerns over its reproducibility. Here we attempted to replicate this important Cannabis regeneration study and expand the original scope of the study by testing it across 10 drug-type C. sativa genotypes to assess genotypic variation. In our study, callus was induced in all 10 genotypes but callus growth and appearance substantially differed among cultivars, with the most responsive genotype producing 6-fold more callus than the least responsive. The shoot induction medium failed to induce shoot organogenesis in any of the 10 cultivars tested, instead resulting in necrosis of the calli. The findings of this replication study raise concerns about the replicability of existing methods. However, some details of the protocol could not be replicated due to missing details in the original paper and regulatory issues, which could have impacted the outcome. These results highlight the importance of using multiple genotypes in such studies and providing detailed methods to facilitate replication.


Assuntos
Cannabis/crescimento & desenvolvimento , Cannabis/genética , Regeneração/genética , Genótipo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Reprodutibilidade dos Testes
9.
Nat Plants ; 7(8): 1078-1092, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34226690

RESUMO

Bidirectional root-shoot signalling is probably key in orchestrating stress responses and ensuring plant survival. Here, we show that Arabidopsis thaliana responses to microbial root commensals and light are interconnected along a microbiota-root-shoot axis. Microbiota and light manipulation experiments in a gnotobiotic plant system reveal that low photosynthetically active radiation perceived by leaves induces long-distance modulation of root bacterial communities but not fungal or oomycete communities. Reciprocally, microbial commensals alleviate plant growth deficiency under low photosynthetically active radiation. This growth rescue was associated with reduced microbiota-induced aboveground defence responses and altered resistance to foliar pathogens compared with the control light condition. Inspection of a set of A. thaliana mutants reveals that this microbiota- and light-dependent growth-defence trade-off is directly explained by belowground bacterial community composition and requires the host transcriptional regulator MYC2. Our work indicates that aboveground stress responses in plants can be modulated by signals from microbial root commensals.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/microbiologia , Adaptação Ocular/fisiologia , Adaptação Fisiológica , Bactérias , Fungos , Regulação da Expressão Gênica de Plantas , Variação Genética , Genótipo , Microbiota/fisiologia , Mutação , Desenvolvimento Vegetal/genética , Desenvolvimento Vegetal/fisiologia , Estresse Fisiológico/fisiologia , Simbiose/genética , Simbiose/fisiologia
10.
Sci Rep ; 11(1): 13769, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215814

RESUMO

Genetic basis and network studies underlying synergistic biomass accumulation of roots and shoots (SBA) are conducive for rational design of high-biomass rice breeding. In this study, association signals for root weight, shoot weight, and the ratio of root-to-shoot mass (R/S) were identified using 666 rice accessions by genome-wide association study, together with their sub-traits, root length, root thickness and shoot length. Most association signals for root weight and shoot weight did not show association with their sub-traits. Based on the results, we proposed a top-to-bottom model for SBA, i.e. root weight, shoot weight and R/S were determined by their highest priority in contributing to biomass in the regulatory pathway, followed by a lower priority pathway for their sub-traits. Owing to 37 enriched clusters with more than two association signals identified, the relationship among the six traits could be also involved in linkage and pleiotropy. Furthermore, a discrimination of pleiotropy and LD at sequencing level using the known gene OsPTR9 for root weight, R/S and root length was provided. The results of given moderate correlation between traits and their corresponding sub-traits, and moderate additive effects between a trait and the accumulation of excellent alleles corresponding to its sub-traits supported a bottom-to-top regulation model for SBA. This model depicted each lowest-order trait (root length, root thickness and shoot length) was determined by its own regulation loci, and competition among different traits, as well as the pleiotropy and LD. All above ensure the coordinated development of each trait and the accumulation of the total biomass, although the predominant genetic basis of SBA is still indistinguishable. The presentation of the above two models and evidence of this study shed light on dissecting the genetic architecture of SBA.


Assuntos
Estudo de Associação Genômica Ampla , Oryza/genética , Melhoramento Vegetal , Locos de Características Quantitativas/genética , Alelos , Biomassa , Ligação Genética , Genótipo , Oryza/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Polimorfismo de Nucleotídeo Único/genética
11.
Sci Rep ; 11(1): 13710, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34211083

RESUMO

It is widely known that during the reproductive stage (flowering), plants do not root well. Most protocols of shoot regeneration in plants utilize juvenile tissue. Adding these two realities together encouraged us to study the role of florigen in shoot regeneration. Mature tobacco tissue that expresses the endogenous tobacco florigen mRNA regenerates poorly, while juvenile tissue that does not express the florigen regenerates shoots well. Inhibition of Nitric Oxide (NO) synthesis reduced shoot regeneration as well as promoted flowering and increased tobacco florigen level. In contrast, the addition of NO (by way of NO donor) to the tissue increased regeneration, delayed flowering, reduced tobacco florigen mRNA. Ectopic expression of florigen genes in tobacco or tomato decreased regeneration capacity significantly. Overexpression pear PcFT2 gene increased regeneration capacity. During regeneration, florigen mRNA was not changed. We conclude that florigen presence in mature tobacco leaves reduces roots and shoots regeneration and is the possible reason for the age-related decrease in regeneration capacity.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Florígeno/metabolismo , Lycopersicon esculentum/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Pyrus/crescimento & desenvolvimento , Tabaco/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Óxido Nítrico/metabolismo , Persea/genética , Persea/crescimento & desenvolvimento , Persea/metabolismo , Desenvolvimento Vegetal , 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/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Pyrus/genética , Pyrus/metabolismo , RNA Mensageiro/genética , Tabaco/genética , Tabaco/metabolismo
12.
Methods Mol Biol ; 2288: 73-88, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270005

RESUMO

In the context of plant regeneration, in vitro systems to produce embryos are frequently used. In many of these protocols, nonzygotic embryos are initiated that will produce shoot-like structures but may lack a primary root. By increasing the auxin-to-cytokinin ratio in the growth medium, roots are then regenerated in a second step. Therefore, in vitro systems might not or only partially execute a similar developmental program as employed during zygotic embryogenesis. There are, however, in vitro systems that can remarkably mimic zygotic embryogenesis such as Brassica microspore-derived embryos. In this case, the patterning process of these haploid embryos closely follows zygotic embryogenesis and all fundamental tissue types are generated in a rather similar manner. In this review, we discuss the most fundamental molecular events during early zygotic embryogenesis and hope that this brief summary can serve as a reference for studying and developing in vitro embryogenesis systems in the context of doubled haploid production.


Assuntos
Magnoliopsida/embriologia , Padronização Corporal/genética , Padronização Corporal/fisiologia , Brassicaceae/embriologia , Brassicaceae/genética , Brassicaceae/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Ácidos Indolacéticos/metabolismo , Sistema de Sinalização das MAP Quinases , Magnoliopsida/genética , Magnoliopsida/fisiologia , Modelos Biológicos , Biologia Molecular/métodos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Regeneração/genética , Regeneração/fisiologia , Nicho de Células-Tronco/genética , Nicho de Células-Tronco/fisiologia , Zigoto
13.
Int J Mol Sci ; 22(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200414

RESUMO

Numerous environmental and endogenous factors affect the level of genetic diversity in natural populations. Genetic variability is the cornerstone of evolution and adaptation of species. However, currently, more and more plant species and local varieties (landraces) are on the brink of extinction due to anthropopression and climate change. Their preservation is imperative for the sake of future breeding programs. Gene banks have been created worldwide to conserve different plant species of cultural and economic importance. Many of them apply cryopreservation, a conservation method in which ultra-low temperatures (-135 °C to -196 °C) are used for long-term storage of tissue samples, with little risk of variation occurrence. Cells can be successfully cryopreserved in liquid nitrogen (LN) when the adverse effect of ice crystal formation and growth is mitigated by the removal of water and the formation of the so-called biological glass (vitrification). This state can be achieved in several ways. The involvement of key cold-regulated genes and proteins in the acquisition of cold tolerance in plant tissues may additionally improve the survival of LN-stored explants. The present review explains the importance of cryostorage in agronomy and presents an overview of the recent works accomplished with this strategy. The most widely used cryopreservation techniques, classic and modern cryoprotective agents, and some protocols applied in crops are considered to understand which parameters provide the establishment of high quality and broadly applicable cryopreservation. Attention is also focused on the issues of genetic integrity and functional genomics in plant cryobiology.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Criopreservação/métodos , Crioprotetores/farmacologia , Melhoramento Vegetal , Brotos de Planta/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Vitrificação , Protoplastos
14.
PLoS One ; 16(7): e0254318, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34314420

RESUMO

Screening for drought tolerance requires precise techniques like phonemics, which is an emerging science aimed at non-destructive methods allowing large-scale screening of genotypes. Large-scale screening complements genomic efforts to identify genes relevant for crop improvement. Thirty maize inbred lines from various sources (exotic and indigenous) maintained at Dryland Agriculture Research Station were used in the current study. In the automated plant transport and imaging systems (LemnaTec Scanalyzer system for large plants), top and side view images were taken of the VIS (visible) and NIR (near infrared) range of the light spectrum to capture phenes. All images were obtained with a thermal imager. All sensors were used to collect images one day after shifting the pots from the greenhouse for 11 days. Image processing was done using pre-processing, segmentation and flowered by features' extraction. Different surrogate traits such as pixel area, plant aspect ratio, convex hull ratio and calliper length were estimated. A strong association was found between canopy temperature and above ground biomass under stress conditions. Promising lines in different surrogates will be utilized in breeding programmes to develop mapping populations for traits of interest related to drought resilience, in terms of improved tissue water status and mapping of genes/QTLs for drought traits.


Assuntos
Secas , Zea mays/fisiologia , Biomassa , Produtos Agrícolas , Genótipo , Processamento de Imagem Assistida por Computador , Fenótipo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Locos de Características Quantitativas , Água/fisiologia , Zea mays/genética , Zea mays/crescimento & desenvolvimento
15.
Cells ; 10(5)2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067728

RESUMO

Cassava brown streak disease (CBSD) is a destructive disease of cassava in Eastern and Central Africa. Because there was no source of resistance in African varieties to provide complete protection against the viruses causing the disease, we searched in South American germplasm and identified cassava lines that did not become infected with the cassava brown streak viruses. These findings motivated further investigations into the mechanism of virus resistance. We used RNAscope® in situ hybridization to localize cassava brown streak virus in cassava germplasm lines that were highly resistant (DSC 167, immune) or that restricted virus infections to stems and roots only (DSC 260). We show that the resistance in those lines is not a restriction of long-distance movement but due to preventing virus unloading from the phloem into parenchyma cells for replication, thus restricting the virus to the phloem cells only. When DSC 167 and DSC 260 were compared for virus invasion, only a low CBSV signal was found in phloem tissue of DSC 167, indicating that there is no replication in this host, while the presence of intense hybridization signals in the phloem of DSC 260 provided evidence for virus replication in companion cells. In neither of the two lines studied was there evidence of virus replication outside the phloem tissues. Thus, we conclude that in resistant cassava lines, CBSV is confined to the phloem tissues only, in which virus replication can still take place or is arrested.


Assuntos
Manihot/virologia , Raízes de Plantas/virologia , Brotos de Planta/virologia , Potyviridae/patogenicidade , Tropismo , Resistência à Doença , Interações Hospedeiro-Patógeno , Manihot/genética , Manihot/crescimento & desenvolvimento , Floema/virologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Potyviridae/crescimento & desenvolvimento , Replicação Viral
16.
PLoS Genet ; 17(6): e1009626, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34181637

RESUMO

How organisms control when to transition between different stages of development is a key question in biology. In plants, epigenetic silencing by Polycomb repressive complex 1 (PRC1) and PRC2 plays a crucial role in promoting developmental transitions, including from juvenile-to-adult phases of vegetative growth. PRC1/2 are known to repress the master regulator of vegetative phase change, miR156, leading to the transition to adult growth, but how this process is regulated temporally is unknown. Here we investigate whether transcription factors in the VIVIPAROUS/ABI3-LIKE (VAL) gene family provide the temporal signal for the epigenetic repression of miR156. Exploiting a novel val1 allele, we found that VAL1 and VAL2 redundantly regulate vegetative phase change by controlling the overall level, rather than temporal dynamics, of miR156 expression. Furthermore, we discovered that VAL1 and VAL2 also act independently of miR156 to control this important developmental transition. In combination, our results highlight the complexity of temporal regulation in plants.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/genética , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 2/genética , Proteínas Repressoras/genética , Alelos , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Epigênese Genética , Regulação da Expressão Gênica de Plantas , MicroRNAs/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Complexo Repressor Polycomb 1/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Tempo
17.
PLoS Genet ; 17(6): e1009636, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34181654

RESUMO

Our previous studies showed that MAN3-mediated mannose plays an important role in plant responses to cadmium (Cd) stress. However, the underlying mechanisms and signaling pathways involved are poorly understood. In this study, we showed that an Arabidopsis MYB4-MAN3-Mannose-MNB1 signaling cascade is involved in the regulation of plant Cd tolerance. Loss-of-function of MNB1 (mannose-binding-lectin 1) led to decreased Cd accumulation and tolerance, whereas overexpression of MNB1 significantly enhanced Cd accumulation and tolerance. Consistently, expression of the genes involved in the GSH-dependent phytochelatin (PC) synthesis pathway (such as GSH1, GSH2, PCS1, and PCS2) was significantly reduced in the mnb1 mutants but markedly increased in the MNB1-OE lines in the absence or presence of Cd stress, which was positively correlated with Cd-activated PC synthesis. Moreover, we found that mannose is able to bind to the GNA-related domain of MNB1, and that mannose binding to the GNA-related domain of MNB1 is required for MAN3-mediated Cd tolerance in Arabidopsis. Further analysis showed that MYB4 directly binds to the promoter of MAN3 to positively regulate the transcript of MAN3 and thus Cd tolerance via the GSH-dependent PC synthesis pathway. Consistent with these findings, overexpression of MAN3 rescued the Cd-sensitive phenotype of the myb4 mutant but not the mnb1 mutant, whereas overexpression of MNB1 rescued the Cd-sensitive phenotype of the myb4 mutant. Taken together, our results provide compelling evidence that a MYB4-MAN3-Mannose-MNB1 signaling cascade regulates cadmium tolerance in Arabidopsis through the GSH-dependent PC synthesis pathway.


Assuntos
Adaptação Fisiológica/genética , Arabidopsis/genética , Lectinas de Ligação a Manose/genética , Manose/metabolismo , Proteínas Repressoras/genética , beta-Manosidase/genética , Aminoaciltransferases/genética , Aminoaciltransferases/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cádmio/toxicidade , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Lectinas de Ligação a Manose/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/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 , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Repressoras/metabolismo , Transdução de Sinais , Poluentes do Solo/toxicidade , beta-Manosidase/metabolismo
18.
Nat Commun ; 12(1): 3656, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34135347

RESUMO

Plants respond to high ambient temperature by implementing a suite of morphological changes collectively termed thermomorphogenesis. Here we show that the above and below ground tissue-response to high ambient temperature are mediated by distinct transcription factors. While the central hub transcription factor, PHYTOCHROME INTERCTING FACTOR 4 (PIF4) regulates the above ground tissue response, the below ground root elongation is primarily regulated by ELONGATED HYPOCOTYL 5 (HY5). Plants respond to high temperature by largely expressing distinct sets of genes in a tissue-specific manner. HY5 promotes root thermomorphogenesis via directly controlling the expression of many genes including the auxin and BR pathway genes. Strikingly, the above and below ground thermomorphogenesis is impaired in spaQ. Because SPA1 directly phosphorylates PIF4 and HY5, SPAs might control the stability of PIF4 and HY5 to regulate thermomorphogenesis in both tissues. These data collectively suggest that plants employ distinct combination of SPA-PIF4-HY5 module to regulate tissue-specific thermomorphogenesis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Brassinosteroides/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Temperatura Alta , Morfogênese/genética , Fosforilação , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Plântula/genética , Plântula/crescimento & desenvolvimento
19.
Nat Plants ; 7(6): 716-724, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34099903

RESUMO

Plants generate a large variety of shoot forms with regular geometries. These forms emerge primarily from the activity of a stem cell niche at the shoot tip. Recent efforts have established a theoretical framework of form emergence at the shoot tip, which has empowered the use of modelling in conjunction with biological approaches to begin to disentangle the biochemical and physical mechanisms controlling form development at the shoot tip. Here, we discuss how these advances get us closer to identifying the construction principles of plant shoot tips. Considering the current limits of our knowledge, we propose a roadmap for developing a general theory of form development at the shoot tip.


Assuntos
Parede Celular , Ácidos Indolacéticos/metabolismo , Meristema/crescimento & desenvolvimento , Modelos Biológicos , Brotos de Planta/crescimento & desenvolvimento , Fenômenos Biomecânicos , Meristema/anatomia & histologia , Meristema/citologia , Células Vegetais/fisiologia , Brotos de Planta/anatomia & histologia , Brotos de Planta/citologia
20.
Mol Genet Genomics ; 296(5): 1071-1083, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34159440

RESUMO

Branching in long-lived plants can cause scarring at the base and affect wood density, which greatly inhibits wood yield and quality. Eucalyptus urophylla is one of the most important commercial forest tree species in South China, with diverse branch number and branch angles under different genetic backgrounds. However, the main elements and regulatory mechanisms associated with different branching traits in E. urophylla remain unclear. To identify the factors that may influence branching, the transcriptome and metabolome were performed on the shoot apex (SA), lateral shoot apex (LSA), and stem segment at the 5th axillary bud from the shoot apex (S1) in lines ZQUC14 (A) and LDUD26 (B), with A exhibiting a smaller Ba than B. A total of 307.3 million high-quality clean reads and nine hormones were identified from six libraries. Several differentially expressed regulatory factors were identified between the two genotypes of E. urophylla. The Kyoto Encyclopedia of Genes and Genomes pathways were enriched in plant hormone signal transduction, plant hormone biosynthesis and their transport pathways. Furthermore, gene expression pattern analysis identified genes that were significantly downregulated or upregulated in S1 relative to the SA and LSA segments, and the plant hormone signal transduction pathway was constructed to explain branching development. This study clarified the main plant hormones and genes underlying branch numbers and angles of E. urophylla, confirmed that ABA and SA could promote a larger branch angle and smaller branch number, while IAA has an opposite function. Numbers of key candidate genes involved in plant hormone signal transduction were found in the positive regulation of branch formation. These novel findings should aid molecular breeding of branching in Eucalyptus.


Assuntos
Eucalyptus/crescimento & desenvolvimento , Eucalyptus/genética , Eucalyptus/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Cromatografia Líquida de Alta Pressão , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genótipo , Reguladores de Crescimento de Plantas/genética , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Caules de Planta/genética , Caules de Planta/metabolismo , Transdução de Sinais/genética , Espectrometria de Massas em Tandem
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