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Plants have evolved diverse defense mechanisms encompassing physical and chemical barriers. Cotton pigment glands are known for containing various defense metabolites, but the precise regulation of gland size to modulate defense compound levels remains enigmatic. Here, it is discovered that the VQ domain-containing protein JAVL negatively regulates pigment gland size and the biosynthesis of defense compounds, while the MYC2-like transcription factor GoPGF has the opposite effect. Notably, GoPGF directly activates the expression of JAVL, whereas JAVL suppresses GoPGF transcription, establishing a negative feedback loop that maintains the expression homeostasis between GoPGF and JAVL. Furthermore, it is observed that JAVL negatively regulates jasmonate levels by inhibiting the expression of jasmonate biosynthetic genes and interacting with GoPGF to attenuate its activation effects, thereby maintaining homeostatic regulation of jasmonate levels. The increased expression ratio of GoPGF to JAVL leads to enlarged pigment glands and elevated jasmonates and defense compounds, enhancing insect and pathogen resistance in cotton. These findings unveil a new mechanism for regulating gland size and secondary metabolites biosynthesis, providing innovative strategies for strengthening plant defense.
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Ciclopentanos , Regulação da Expressão Gênica de Plantas , Gossypium , Oxilipinas , Fitoalexinas , Sesquiterpenos , Gossypium/genética , Gossypium/metabolismo , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Sesquiterpenos/metabolismo , Retroalimentação Fisiológica , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
Sphingolipids are components of plant membranes, and their heterogeneous distribution gives different membrane systems distinct properties. For example, glycosyl inositol phosphoceramides (GIPCs), 1 major type of sphingolipids, aggregate in the outer layer of the plasma membrane (PM), as well as in extracellular vesicles (EVs), including the small (30 to 100â nm) EVs termed exosomes. How these sphingolipids are sorted and trafficked is not clear. In this work, we report that Arabidopsis thaliana TETRASPANIN8 (TET8) acts as a sphingolipid carrier and thus regulates the export of GIPCs from the Golgi apparatus. TET8 recognized the coat protein complex I (COPI) subunit γ2-COPI and moved to its proper location in the PM; this recognition required the TET8 C-terminal tail. Deleting the C-terminal tail of TET8 largely restricted its roles in GIPC transport and endosomal trafficking. Further, we show that TET8 affects EV secretion in association with GIPCs. Thus, our findings shed light on GIPC transport and the molecular machinery involved in EV biogenesis.
Assuntos
Arabidopsis , Exossomos , Arabidopsis/genética , Arabidopsis/metabolismo , Exossomos/metabolismo , Inositol/metabolismo , Esfingolipídeos , Complexo I de Proteína do Envoltório/metabolismoRESUMO
Plants can synthesize a wide range of terpenoids in response to various environmental cues. However, the specific regulatory mechanisms governing terpenoid biosynthesis at the cellular level remain largely elusive. In this study, we employed single-cell RNA sequencing to comprehensively characterize the transcriptome profile of cotton leaves and established a hierarchical transcriptional network regulating cell-specific terpenoid production. We observed substantial expression levels of genes associated with the biosynthesis of both volatile terpenes (such as ß-caryophyllene and ß-myrcene) and non-volatile gossypol-type terpenoids in secretory glandular cells. Moreover, two novel transcription factors, namely GoHSFA4a and GoNAC42, are identified to function downstream of the Gossypium PIGMENT GLAND FORMATION genes. Both transcription factors could directly regulate the expression of terpenoid biosynthetic genes in secretory glandular cells in response to developmental and environmental stimuli. For convenient retrieval of the single-cell RNA sequencing data generated in this study, we developed a user-friendly web server . Our findings not only offer valuable insights into the precise regulation of terpenoid biosynthesis genes in cotton leaves but also provide potential targets for cotton breeding endeavors.
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Redes Reguladoras de Genes , Gossypium , Gossypium/genética , Gossypium/metabolismo , Melhoramento Vegetal , Terpenos/metabolismo , Transcriptoma/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Análise de Sequência de RNA , Regulação da Expressão Gênica de PlantasRESUMO
Introduction: With social and economic development and the associated large-scale exploitation of natural resources, the number of slopes has significantly increased. As slope instability can lead to serious geological disasters, the ecological protection and reconstruction of slopes has become a hot topic of common global concern. Methods: In order to achieve scientific slope management and overcome the difficulty of maintaining slope greening in the long term, this study explored eight strategies (A, B, C, AB, AC, BC, ABC, CK), involving different patented mineral solubilizing microorganisms (MSMs), and analyzed the field application of active permanent greening (APG) based on MSMs. Results: The results revealed that MSMs significantly increased the content of effective metal ions and available nutrients in soil and enhanced soil enzyme activity. Among all strategies, strategy A showed significant superiority, with soil effective calcium, magnesium, potassium, nitrogen, phosphorus and organic matter contents increasing by 51.62%, 55.41%, 30.42%, 39.77%, 181.69% and 76.92%, respectively, while urease, sucrase and peroxidase activities increased by 89.59%, 74.68% and 85.30%. MSMs strongly promoted the growth of Amorpha. Strategy A showed the best performance, with plant seedling height, ground diameter, leaf area, root length, and root volume increasing by 95.75%, 47.78%, 124.14%, 108.83%, and 139. 86%, respectively. According to a comprehensive evaluation using the entropy-analysis hierarchy process, strategy A has great potential for application. The field test results verified that APG has significantly better greening performance than the traditional greening method, with high vegetation cover and stable soil layer. Discussion: The results of this study provide a reliable practical basis and technical reference for the development, promotion, and application of APG.
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Cotton is an irreplaceable economic crop currently domesticated in the human world for its extremely elongated fiber cells specialized in seed epidermis, which makes it of high research and application value. To date, numerous research on cotton has navigated various aspects, from multi-genome assembly, genome editing, mechanism of fiber development, metabolite biosynthesis, and analysis to genetic breeding. Genomic and 3D genomic studies reveal the origin of cotton species and the spatiotemporal asymmetric chromatin structure in fibers. Mature multiple genome editing systems, such as CRISPR/Cas9, Cas12 (Cpf1) and cytidine base editing (CBE), have been widely used in the study of candidate genes affecting fiber development. Based on this, the cotton fiber cell development network has been preliminarily drawn. Among them, the MYB-bHLH-WDR (MBW) transcription factor complex and IAA and BR signaling pathway regulate the initiation; various plant hormones, including ethylene, mediated regulatory network and membrane protein overlap fine-regulate elongation. Multistage transcription factors targeting CesA 4, 7, and 8 specifically dominate the whole process of secondary cell wall thickening. And fluorescently labeled cytoskeletal proteins can observe real-time dynamic changes in fiber development. Furthermore, research on the synthesis of cotton secondary metabolite gossypol, resistance to diseases and insect pests, plant architecture regulation, and seed oil utilization are all conducive to finding more high-quality breeding-related genes and subsequently facilitating the cultivation of better cotton varieties. This review summarizes the paramount research achievements in cotton molecular biology over the last few decades from the above aspects, thereby enabling us to conduct a status review on the current studies of cotton and provide strong theoretical support for the future direction.
Assuntos
Genômica , Melhoramento Vegetal , Humanos , Fatores de Transcrição/metabolismo , Biotecnologia , Reguladores de Crescimento de Plantas/metabolismo , Gossypium/genética , Gossypium/metabolismo , Fibra de Algodão , Regulação da Expressão Gênica de PlantasRESUMO
Axial chirality of biaryls can generate varied bioactivities. Gossypol is a binaphthyl compound made by cotton plants. Of its two axially chiral isomers, (-)-gossypol is the bioactive form in mammals and has antispermatogenic activity, and its accumulation in cotton seeds poses health concerns. Here we identified two extracellular dirigent proteins (DIRs) from Gossypium hirsutum, GhDIR5 and GhDIR6, which impart the hemigossypol oxidative coupling into (-)- and (+)-gossypol, respectively. To reduce cotton seed toxicity, we disrupted GhDIR5 by genome editing, which eliminated (-)-gossypol but had no effects on other phytoalexins, including (+)-gossypol, that provide pest resistance. Reciprocal mutagenesis identified three residues responsible for enantioselectivity. The (-)-gossypol-forming DIRs emerged later than their enantiocomplementary counterparts, from tandem gene duplications that occurred shortly after the cotton genus diverged. Our study offers insight into how plants control enantiomeric ratios and how to selectively modify the chemical spectra of cotton plants and thereby improve crop quality.
Assuntos
Gossipol , Animais , Gossipol/toxicidade , Gossipol/análise , Gossipol/química , Edição de Genes , Gossypium/genética , Gossypium/metabolismo , Sementes/metabolismo , Mamíferos/genéticaRESUMO
Introduction: The stability of exposed slopes is prone to natural disasters, seriously threatening socio-economic and human security. Through years of exploration and research, we proposed an active permanent greening (APG) method based on patented mineral solubilizing microorganisms (MSMs) as an improvement over the traditional greening method. Methods: In this study, we selected two MSMs (Bacillus thuringiensis and Gongronella butleri) and a plant species (Lolium perenne L.) set up six treatments (T1, T2, T3, T4, T5, and T6) to investigate the effectiveness of the MSMs and their combinations with the plant species on the soil stability using APG method. Results: We noted that both MSMs and the plant species significantly improved soil aggregate stability and organic matter content. Of all the treatments, the T1 treatment exhibited better results, with soil aggregate stability and organic matter content increased to 45.63% and 137.57%, respectively, compared to the control. Soil stability was significant positively correlated with macroaggregate content and negatively with microaggregates. Using structural equation modeling analysis, we further evaluated the mechanism underpinning the influence of organic matter content and fractions on the content of each graded agglomerates. The analysis showed that the macroaggregate content was influenced by the presence of the plant species, primarily realized by altering the content of organic matter and aromatic and amide compounds in the agglomerates, whereas the microaggregate content was influenced by the addition of MSMs, primarily realized by the content of organic matter and polysaccharide compounds. Overall, we observed that the effect of the co-action of MSMs and the plant species was significantly better than that of using MSMs or the plant species alone. Discussion: The findings of this study provide reliable data and theoretical support for the development and practical application of the APG method to gradually develop and improve the new greening approach.
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N6-methyladenosine (m6A) RNA modification plays important regulatory roles in plant development and adapting to the environment, which requires methyltransferases to achieve the methylation process. However, there has been no research regarding m6A RNA methyltransferases in cotton. Here, a systematic analysis of the m6A methyltransferase (METTL) gene family was performed on twelve cotton species, resulting in six METTLs identified in five allotetraploid cottons, respectively, and three to four METTLs in the seven diploid species. Phylogenetic analysis of protein-coding sequences revealed that METTL genes from cottons, Arabidopsis thaliana, and Homo sapiens could be classified into three clades (METTL3, METTL14, and METTL-like clades). Cis-element analysis predicated the possible functions of METTL genes in G. hirsutum. RNA-seq data revealed that GhMETTL14 (GH_A07G0817/GH_D07G0819) and GhMETTL3 (GH_A12G2586/GH_D12G2605) had high expressions in root, stem, leaf, torus, petal, stamen, pistil, and calycle tissues. GhMETTL14 also had the highest expression in 20 and 25 dpa fiber cells, implying a potential role at the cell wall thickening stage. Suppressing GhMETTL3 and GhMETTL14 by VIGS caused growth arrest and even death in G. hirsutum, along with decreased m6A abundance from the leaf tissues of VIGS plants. Overexpression of GhMETTL3 and GhMETTL14 produced distinct differentially expressed genes (DEGs) in A. thaliana, indicating their possible divergent functions after gene duplication. Overall, GhMETTLs play indispensable but divergent roles during the growth of cotton plants, which provides the basis for the systematic investigation of m6A in subsequent studies to improve the agronomic traits in cotton.
Assuntos
Regulação da Expressão Gênica de Plantas , Gossypium , Metiltransferases , Humanos , Genômica , Gossypium/genética , Metiltransferases/genética , Filogenia , RNARESUMO
The widely cultivated medicinal and ornamental plant sage (Salvia officinalis L.) is an evergreen shrub of the Lamiaceae family, native to the Mediterranean. We assembled a high-quality sage genome of 480 Mb on seven chromosomes, and identified a biosynthetic gene cluster (BGC) encoding two pairs of diterpene synthases (diTPSs) that, together with the cytochromes P450 (CYPs) genes located inside and outside the cluster, form two expression cascades responsible for the shoot and root diterpenoids, respectively, thus extending BGC functionality from co-regulation to orchestrating metabolite production in different organs. Phylogenomic analysis indicates that the Salvia clades diverged in the early Miocene. In East Asia, most Salvia species are herbaceous and accumulate diterpenoids in storage roots. Notably, in Chinese sage S. miltiorrhiza, the diterpene BGC has contracted and the shoot cascade has been lost. Our data provide genomic insights of micro-evolution of growth type-associated patterning of specialized metabolite production in plants.
Assuntos
Diterpenos , Salvia , Família Multigênica , Filogenia , Plantas/genética , Salvia/genética , Salvia/metabolismoRESUMO
Plant trichomes are specialized epidermal cells that protect plants from insects and pathogens. In Arabidopsis, epidermal hairs decrease as internodes increase in height, with only few epidermal hairs produced on the sepals abaxial surface of the early flowers. TRIPTYCHON (TRY) is known to be a negative regulator of epidermal hair development in Arabidopsis, suppressing the formation of ectopic epidermal hairs in the inflorescence. Here, we reported that the second intron of TRY gene plays a critical role in trichome spatial distribution in Arabidopsis. The expression of TRY rises with the increasing stem nodes and reaches the peak in the inflorescence, while the trichomes distribution decrease. The transgenic plants showed that TRY promoter could only drive the genomic instead of coding sequences combined with GUS reporter gene, which indicates that the regulatory elements of TRY expression in inflorescence could be located in the intron regions. Multiple SPLs and MADS-box binding sites were found in the TRY intron2 sequence. Further genetic and biochemistry assays revealed that the flowering-related genes such as SPL9 could bind to these cis-elements directly, contributing to the TRY spatial expression. Since cotton fiber and Arabidopsis trichomes share similar regulatory mechanism, extended analysis showed that the intron2 of cotton TRY genes also contain the cis-elements. Thus, the introns harboring the transcription element may be the general way to regulate the gene expression in different plants and provides molecular clues for the related crops' traits design.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Inflorescência/genética , Inflorescência/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Transativadores/metabolismoRESUMO
BACKGROUND: The cryptochromes (CRY) are specific blue light receptors of plants and animals, which play crucial roles in physiological processes of plant growth, development, and stress tolerance. RESULTS: In the present work, a systematic analysis of the CRY gene family was performed on twelve cotton species, resulting in 18, 17, 17, 17, and 17 CRYs identified in five alloteraploid cottons (Gossypium hirsutum, G. barbadense, G. tomentosum, G. mustelinum and G. darwinii), respectively, and five to nine CRY genes in the seven diploid species. Phylogenetic analysis of protein-coding sequences revealed that CRY genes from cottons and Arabidopsis thaliana could be classified into seven clades. Synteny analysis suggested that the homoeolog of G. hirsutum Gh_A02G0384 has undergone an evolutionary loss event in the other four allotetraploid cotton species. Cis-element analysis predicated the possible functions of CRY genes in G. hirsutum. RNA-seq data revealed that Gh_D09G2225, Gh_A09G2012 and Gh_A11G1040 had high expressions in fiber cells of different developmental states. In addition, the expression levels of one (Gh_A03G0120), 15 and nine GhCRY genes were down-regulated following the PEG, NaCl and high-temperature treatments, respectively. For the low-temperature treatment, five GhCRY genes were induced, and five were repressed. These results indicated that most GhCRY genes negatively regulate the abiotic stress treatments. CONCLUSION: We report the structures, domains, divergence, synteny, and cis-elements analyses systematically of G. hirsutum CRY genes. Possible biological functions of GhCRY genes in differential tissues as well as in response to abiotic stress during the cotton plant life cycle were predicted.
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Criptocromos , Gossypium , Criptocromos/genética , Regulação da Expressão Gênica de Plantas , Gossypium/fisiologia , Família Multigênica , FilogeniaRESUMO
Sphingolipids, which comprise membrane systems together with other lipids, are ubiquitous in cellular organisms. They show a high degree of diversity across plant species and vary in their structures, properties, and functions. Benefiting from the development of lipidomic techniques, over 300 plant sphingolipids have been identified. Generally divided into free long-chain bases (LCBs), ceramides, glycosylceramides (GlcCers) and glycosyl inositol phosphoceramides (GIPCs), plant sphingolipids exhibit organized aggregation within lipid membranes to form raft domains with sterols. Accumulating evidence has revealed that sphingolipids obey certain trafficking and distribution rules and confer unique properties to membranes. Functional studies using sphingolipid biosynthetic mutants demonstrate that sphingolipids participate in plant developmental regulation, stimulus sensing, and stress responses. Here, we present an updated metabolism/degradation map and summarize the structures of plant sphingolipids, review recent progress in understanding the functions of sphingolipids in plant development and stress responses, and review sphingolipid distribution and trafficking in plant cells. We also highlight some important challenges and issues that we may face during the process of studying sphingolipids.
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Plantas/metabolismo , Esfingolipídeos/metabolismo , Transporte BiológicoRESUMO
The exquisite chemodiversity of terpenoids is the product of the large diverse terpene synthase (TPS) superfamily. Here, by using structural and phylogenetic analyses and site-directed mutagenesis, we identified a residue (Cys440 in Nicotiana tabacum 5-epi-aristolochene synthase) proximal to an ion-binding motif common to all TPSs and named the preNSE/DTE residue, which determines the product specificity of sesquiterpene synthases from different plant species. In sesquiterpene synthases catalyzing 1,10-cyclization (1,10-cyclases) of farnesyl diphosphate, mutation of the residue in both specific and promiscuous 1,10-cyclases from different lineages leads to the accumulation of monocyclic germacrene A-11-ol, which is "short-circuited" from complex cyclization cascades, suggesting a key role of this residue in generating the first common intermediate of 1,10-cyclization. Altering this residue in a specific 1,11-cyclase results in alternative 1,10-cyclization products. Moreover, the preNSE/DTE residue can be harnessed to engineer highly specific sesquiterpene synthases for an improved proportion of high-value terpenoids, such as patchoulol, a main constituent of several traditional Chinese medicines that could treat SARS-CoV-2.
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Alquil e Aril Transferases/química , Alquil e Aril Transferases/metabolismo , Biocatálise , Alquil e Aril Transferases/genética , Domínio Catalítico , Ciclização , Modelos Moleculares , Mutagênese Sítio-Dirigida , Filogenia , Nicotiana/enzimologiaRESUMO
BACKGROUND: Cotton fiber is a model system for studying plant cell development. At present, the functions of many transcription factors in cotton fiber development have been elucidated, however, the roles of auxin response factor (ARF) genes in cotton fiber development need be further explored. RESULTS: Here, we identify auxin response factor (ARF) genes in three cotton species: the tetraploid upland cotton G. hirsutum, which has 73 ARF genes, and its putative extent parental diploids G. arboreum and G. raimondii, which have 36 and 35 ARFs, respectively. Ka and Ks analyses revealed that in G. hirsutum ARF genes have undergone asymmetric evolution in the two subgenomes. The cotton ARFs can be classified into four phylogenetic clades and are actively expressed in young tissues. We demonstrate that GhARF2b, a homolog of the Arabidopsis AtARF2, was preferentially expressed in developing ovules and fibers. Overexpression of GhARF2b by a fiber specific promoter inhibited fiber cell elongation but promoted initiation and, conversely, its downregulation by RNAi resulted in fewer but longer fiber. We show that GhARF2b directly interacts with GhHOX3 and represses the transcriptional activity of GhHOX3 on target genes. CONCLUSION: Our results uncover an important role of the ARF factor in modulating cotton fiber development at the early stage.
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Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Fibra de Algodão , Diploide , Gossypium/genética , Gossypium/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Pancreatic ductal adenocarcinoma (PDAC), one of the most lethal human cancers, can be divided into head and body/tail cancers anatomically. We previously reported a prognostic relevance of tumour location in resectable PDAC. This study aimed to further explore the mechanism underlying the molecular diversity between the head and body/tail of PDACs. We detected tumour genomes in 154 resectable (surgery) and non-resectable (biopsy) PDACs using a next-generation sequencing panel. Wilcoxon's rank test or Fisher's exact test was used for evaluating associations between clinical characteristics, mutation frequency and survival probability between the two cohorts. Compared with pancreatic head cancers, pancreatic body/tail cancers showed significantly more enriched genomic alterations in KRAS (97.1% vs 82.4%, P = 0.004) and SMAD4 (42.0% vs 21.2%, P = 0.008). At early stages (I-II), the SMAD4 mutation rate was significantly higher in pancreatic body/tail cancers than pancreatic head cancers (56.0% vs 26.5%, P = 0.021). At late stages (III-IV), pancreatic body/tail cancers presented significantly higher KRAS mutation rate (100.0% vs 75.8%, P = 0.001), higher frequency of MAPK pathway mutation (100% vs 87.8%, P = 0.040) and lower rates of druggable genomic alterations (30.8% vs 57.6%, P = 0.030) than pancreatic head cancers. Our work points out that pancreatic body/tail cancer seems to be more malignant than pancreatic head cancer at late stages.
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Biomarcadores Tumorais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Genômica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/mortalidade , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Prognóstico , Transdução de SinaisRESUMO
Almost all plants form trichomes, which protect them against insect herbivores by forming a physical barrier and releasing chemical repellents. Glandular trichomes produce a variety of specialized defensive metabolites, including volatile terpenes. Previous studies have shown that the defence hormone jasmonic acid (JA) affects trichome development and induces terpene synthases (TPSs) but the underlying molecular mechanisms remain unclear. Here, we characterized a loss-of-function allele of the HD-ZIP IV transcription factor woolly (wo) and analysed its role in mediating JA signalling in tomato. We showed that knockout of wo led to extensive trichome defects, including structural and functional changes in type VI glandular trichomes, and a dramatic reduction in terpene levels. We further found that wo directly binds to TPS gene promoters to recruit SlMYC1, a JA signalling modulator, and that together these transcription factors promote terpene biosynthesis in tomato trichomes. The wo/SlMYC1 regulatory module is inhibited by SlJAZ2 through a competitive binding mechanism, resulting in a fine-tuned JA response in tomato trichomes. Enhanced expression of SlMYC1 substantially increased terpene levels and improved tomato resistance to spider mites. Interestingly, we also found that SlMYC1 plays an additional role in glandular cell division and expansion in type VI trichomes, independent of JA. Together, our results reveal a novel, JA-mediated regulatory mechanism that promotes insect resistance in tomato.
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Solanum lycopersicum , Tricomas , Ciclopentanos , Solanum lycopersicum/genética , Oxilipinas , Folhas de PlantaRESUMO
The plant extracellular vesicles (EVs) are lipid-enveloped nano-particles containing proteins, nucleic acids and metabolites and function in plant development and response. The Arabidopsis four transmembrane protein TETRASPANIN 8 (TET8) knock-out mutant tet8 secreted less EVs than the wild-type (WT). In this report, we show that the tet8 mutant was attenuated in the plant hormone jasmonate (JA) accumulation in response to mechanical wounding treatment. We also noticed that the EVs contained a high level of phospholipids phosphatidic acids (PAs) which may serve as precursors of JA biosynthesis during wound-triggered-self-healing processes. Thus, we propose an open question about a potential role of EVs or TET8 or both in damage-associated JA response.
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Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Vesículas Extracelulares/metabolismo , Oxilipinas/metabolismo , Folhas de Planta/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Vias Biossintéticas , Mutação/genética , Ácidos Fosfatídicos/metabolismo , RegeneraçãoRESUMO
BACKGROUND: Cotton (Gossypium spp.) is the most important world-wide fiber crop but salt stress limits cotton production in coastal and other areas. Growth regulation factors (GRFs) play regulatory roles in response to salt stress, but their roles have not been studied in cotton under salt stress. RESULTS: We identified 19 GRF genes in G. raimondii, 18 in G. arboreum, 34 in G. hirsutum and 45 in G. barbadense, respectively. These GRF genes were phylogenetically analyzed leading to the recognition of seven GRF clades. GRF genes from diploid cottons (G. raimondii and G. arboreum) were largely retained in allopolyploid cotton, with subsequent gene expansion in G. barbadense relative to G. hirsutum. Most G. hirsutum GRF (GhGRF) genes are preferentially expressed in young and growing tissues. To explore their possible role in salt stress, we used qRT-PCR to study expression responses to NaCl treatment, showing that five GhGRF genes were down-regulated in leaves. RNA-seq experiments showed that seven GhGRF genes exhibited decreased expression in leaves under NaCl treatment, three of which (GhGRF3, GhGRF4, and GhGRF16) were identified by both RNA-seq and qRT-PCR. We also identified six and three GRF genes that exhibit decreased expression under salt stress in G. arboreum and G. barbadense, respectively. Consistent with its lack of leaf withering or yellowing under the salt treatment conditions, G. arboreum had better salt tolerance than G. hirsutum and G. barbadense. Our results suggest that GRF genes are involved in salt stress responses in Gossypium. CONCLUSION: In summary, we identified candidate GRF genes that were involved in salt stress responses in cotton.
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Regulação da Expressão Gênica de Plantas , Gossypium , Gossypium/genética , Gossypium/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse SalinoRESUMO
Plant extracellular vesicles (EVs) are membrane-enclosed nanoparticles that play diverse roles in plant development and response. Recently, impressive progress has been made in the isolation and identification of the proteins and RNAs carried in plant EVs; however, the analysis of EV lipid compositions remains rudimentary. Here, we performed lipidomic analysis of Arabidopsis rosette leaf EVs, revealing a high abundance of certain groups of lipids, in particular sphingolipids, in the EVs. Remarkably, the EV sphingolipids are composed of nearly pure glycosylinositolphosphoceramides (GIPCs), which are green lineage abundant and negatively charged. We further showed that the Arabidopsis TETRASPANIN 8 (TET8) knockout mutant has a lower amount of cellular GIPCs and secrets fewer EVs, companied with impaired reactive oxygen species (ROS) burst toward stresses. Exogenous application of GIPCs promoted the secretion of EVs and ROS burst in both the WT and tet8 mutant. The characteristic enrichment of sphingolipid GIPCs provides valuable insights into the biogenesis and function of plant EVs.
Assuntos
Arabidopsis/metabolismo , Vesículas Extracelulares/metabolismo , Lipidômica/métodos , Folhas de Planta/metabolismo , Glicoesfingolipídeos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Esfingolipídeos/metabolismoRESUMO
The reactive electrophilic species (RES), typically the molecules bearing α,ß-unsaturated carbonyl group, are widespread in living organisms and notoriously known for their damaging effects. Many of the mycotoxins released from phytopathogenic fungi are RES and their contamination to cereals threatens food safety worldwide. However, due to their high reactivity, RES are also used by host organisms to synthesize specific metabolites. The evolutionary conserved glyoxalase (GLX) system scavenges the cytotoxic α-oxoaldehydes that bear RES groups, which cause host disorders and diseases. In cotton, a specialized enzyme derived from glyoxalase I (GLXI) through gene duplications and named as specialized GLXI (SPG), acts as a distinct type of aromatase in the gossypol pathway to transform the RES intermediates into the phenolic products. In this review, we briefly introduce the research progress in understanding the RES, especially the RES-type mycotoxins, the GLX system and SPG, and discuss their application potential in detoxification and synthetic biology.