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1.
BMC Genomics ; 25(1): 631, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914930

RESUMO

BACKGROUND: Current RNA-seq analysis software for RNA-seq data tends to use similar parameters across different species without considering species-specific differences. However, the suitability and accuracy of these tools may vary when analyzing data from different species, such as humans, animals, plants, fungi, and bacteria. For most laboratory researchers lacking a background in information science, determining how to construct an analysis workflow that meets their specific needs from the array of complex analytical tools available poses a significant challenge. RESULTS: By utilizing RNA-seq data from plants, animals, and fungi, it was observed that different analytical tools demonstrate some variations in performance when applied to different species. A comprehensive experiment was conducted specifically for analyzing plant pathogenic fungal data, focusing on differential gene analysis as the ultimate goal. In this study, 288 pipelines using different tools were applied to analyze five fungal RNA-seq datasets, and the performance of their results was evaluated based on simulation. This led to the establishment of a relatively universal and superior fungal RNA-seq analysis pipeline that can serve as a reference, and certain standards for selecting analysis tools were derived for reference. Additionally, we compared various tools for alternative splicing analysis. The results based on simulated data indicated that rMATS remained the optimal choice, although consideration could be given to supplementing with tools such as SpliceWiz. CONCLUSION: The experimental results demonstrate that, in comparison to the default software parameter configurations, the analysis combination results after tuning can provide more accurate biological insights. It is beneficial to carefully select suitable analysis software based on the data, rather than indiscriminately choosing tools, in order to achieve high-quality analysis results more efficiently.


Assuntos
RNA-Seq , Software , Fluxo de Trabalho , RNA-Seq/métodos , Fungos/genética , Biologia Computacional/métodos , Análise de Sequência de RNA/métodos , Processamento Alternativo
2.
Plant Biotechnol J ; 22(8): 2113-2128, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38470397

RESUMO

Plants face a relentless onslaught from a diverse array of pathogens in their natural environment, to which they have evolved a myriad of strategies that unfold across various temporal scales. Cell surface pattern recognition receptors (PRRs) detect conserved elicitors from pathogens or endogenous molecules released during pathogen invasion, initiating the first line of defence in plants, known as pattern-triggered immunity (PTI), which imparts a baseline level of disease resistance. Inside host cells, pathogen effectors are sensed by the nucleotide-binding/leucine-rich repeat (NLR) receptors, which then activate the second line of defence: effector-triggered immunity (ETI), offering a more potent and enduring defence mechanism. Moreover, PTI and ETI collaborate synergistically to bolster disease resistance and collectively trigger a cascade of downstream defence responses. This article provides a comprehensive review of plant defence responses, offering an overview of the stepwise activation of plant immunity and the interactions between PTI-ETI synergistic signal transduction.


Assuntos
Imunidade Vegetal , Transdução de Sinais , Receptores de Reconhecimento de Padrão/metabolismo , Receptores de Reconhecimento de Padrão/imunologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Plantas/imunologia , Plantas/metabolismo , Resistência à Doença/imunologia
3.
New Phytol ; 242(5): 2043-2058, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38515251

RESUMO

MicroRNAs are essential in plant development and stress resistance, but their specific roles in drought stress require further investigation. Here, we have uncovered that a Populus-specific microRNAs (miRNA), miR6445, targeting NAC (NAM, ATAF, and CUC) family genes, is involved in regulating drought tolerance of poplar. The expression level of miR6445 was significantly upregulated under drought stress; concomitantly, seven targeted NAC genes showed significant downregulation. Silencing the expression of miR6445 by short tandem target mimic technology significantly decreased the drought tolerance in poplar. Furthermore, 5' RACE experiments confirmed that miR6445 directly targeted NAC029. The overexpression lines of PtrNAC029 (OE-NAC029) showed increased sensitivity to drought compared with knockout lines (Crispr-NAC029), consistent with the drought-sensitive phenotype observed in miR6445-silenced strains. PtrNAC029 was further verified to directly bind to the promoters of glutathione S-transferase U23 (GSTU23) and inhibit its expression. Both Crispr-NAC029 and PtrGSTU23 overexpressing plants showed higher levels of PtrGSTU23 transcript and GST activity while accumulating less reactive oxygen species (ROS). Moreover, poplars overexpressing GSTU23 demonstrated enhanced drought tolerance. Taken together, our research reveals the crucial role of the miR6445-NAC029-GSTU23 module in enhancing poplar drought tolerance by regulating ROS homeostasis. This finding provides new molecular targets for improving the drought resistance of trees.


Assuntos
Resistência à Seca , Glutationa Transferase , MicroRNAs , Proteínas de Plantas , Populus , Espécies Reativas de Oxigênio , Adaptação Fisiológica , Sequência de Bases , Sequestradores de Radicais Livres/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Populus/genética , Populus/fisiologia , Populus/enzimologia , Regiões Promotoras Genéticas/genética , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética
4.
Plant Cell Environ ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39318109

RESUMO

Changes in root system architecture are vital for plant adaptation to drought stress, yet the underlying molecular mechanisms of this process remain largely elusive. Here, FUSCA3 (FUS3), a B3 domain transcription factor isolated from Populus euphratica, was found to be an important gene of regulating lateral root (LR) development under drought stress. The expression of PeFUS3 was strongly induced by ABA and dehydration treatments. Overexpressing PeFUS3 in poplar 84 K (P. alba × P. glandulosa) positively regulated LR growth and enhanced drought tolerance, while the knockout lines, generated by the CRISPR/Cas9 system, displayed repressed LR growth and weakened drought tolerance. Further investigation demonstrated that PeFUS3 activated the expression of PIN2, PIN6a and AUX1, which were key genes involved in auxin transport, suggesting PeFUS3 modulated LR development under drought stress through auxin signalling. Moreover, PeFUS3 directly upregulated PePYL3 expression, and overexpressing PePYL3 poplar lines exhibited significantly increased drought resistance. In addition, PeABF2, an ABA responsive transcription factor, interacted with PeFUS3 and activated its transcription, indicating PeFUS3 was involved in ABA signalling pathway. Taken together, PeFUS3 is a key regulator, maintaining root growth of poplar by modulating the crosstalk of auxin and ABA signalling under drought stress.

5.
Plant Cell ; 33(5): 1594-1614, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-33793897

RESUMO

During leaf senescence, the final stage of leaf development, nutrients are recycled from leaves to other organs, and therefore proper control of senescence is thus critical for plant fitness. Although substantial progress has been achieved in understanding leaf senescence in annual plants, the molecular factors that control leaf senescence in perennial woody plants are largely unknown. Using RNA sequencing, we obtained a high-resolution temporal profile of gene expression during autumn leaf senescence in poplar (Populus tomentosa). Identification of hub transcription factors (TFs) by co-expression network analysis of genes revealed that senescence-associated NAC family TFs (Sen-NAC TFs) regulate autumn leaf senescence. Age-dependent alternative splicing (AS) caused an intron retention (IR) event in the pre-mRNA encoding PtRD26, a NAC-TF. This produced a truncated protein PtRD26IR, which functions as a dominant-negative regulator of senescence by interacting with multiple hub Sen-NAC TFs, thereby repressing their DNA-binding activities. Functional analysis of senescence-associated splicing factors identified two U2 auxiliary factors that are involved in AS of PtRD26IR. Correspondingly, silencing of these factors decreased PtRD26IR transcript abundance and induced early senescence. We propose that an age-dependent increase of IR splice variants derived from Sen-NAC TFs is a regulatory program to fine tune the molecular mechanisms that regulate leaf senescence in trees.


Assuntos
Processamento Alternativo/genética , Folhas de Planta/genética , Proteínas de Plantas/genética , Populus/genética , Fatores de Transcrição/genética , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Modelos Biológicos , Proteínas de Plantas/metabolismo , Populus/crescimento & desenvolvimento , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estações do Ano , Fatores de Tempo , Fatores de Transcrição/metabolismo
6.
BMC Plant Biol ; 23(1): 604, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38030990

RESUMO

BACKGROUND: The WUSCHEL-related Homeobox (WOX) genes, which encode plant-specific homeobox (HB) transcription factors, play crucial roles in regulating plant growth and development. However, the functions of WOX genes are little known in Eucalyptus, one of the fastest-growing tree resources with considerable widespread cultivation worldwide. RESULTS: A total of nine WOX genes named EgWOX1-EgWOX9 were retrieved and designated from Eucalyptus grandis. From the three divided clades marked as Modern/WUS, Intermediate and Ancient, the largest group Modern/WUS (6 EgWOXs) contains a specific domain with 8 amino acids: TLQLFPLR. The collinearity, cis-regulatory elements, protein-protein interaction network and gene expression analysis reveal that the WUS proteins in E. grandis involve in regulating meristems development and regeneration. Furthermore, by externally adding of truncated peptides isolated from WUS specific domain, the transformation efficiency in E. urophylla × E. grandis DH32-29 was significant enhanced. The transcriptomics data further reveals that the use of small peptides activates metabolism pathways such as starch and sucrose metabolism, phenylpropanoid biosynthesis and flavonoid biosynthesis. CONCLUSIONS: Peptides isolated from WUS protein can be utilized to enhance the transformation efficiency in Eucalyptus, thereby contributing to the high-efficiency breeding of Eucalyptus.


Assuntos
Eucalyptus , Genes Homeobox , Eucalyptus/genética , Eucalyptus/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Melhoramento Vegetal , Peptídeos/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia
7.
New Phytol ; 240(3): 1116-1133, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37608617

RESUMO

The regulatory framework of leaf senescence is gradually becoming clearer; however, the fine regulation of this process remains largely unknown. Here, genetic analysis revealed that U2 small nuclear ribonucleoprotein B (U2B″), a component of the spliceosome, is a negative regulator of leaf senescence. Mutation of U2B″ led to precocious leaf senescence, whereas overexpression of U2B″ extended leaf longevity. Transcriptome analysis revealed that the jasmonic acid (JA) signaling pathway was activated in the u2b″ mutant. U2B″ enhances the generation of splicing variant JASMONATE ZIM-DOMAIN 9ß (JAZ9ß) with an intron retention in the Jas motif, which compromises its interaction with CORONATINE INSENSITIVE1 and thus enhances the stability of JAZ9ß protein. Moreover, JAZ9ß could interact with MYC2 and obstruct its activity, thereby attenuating JA signaling. Correspondingly, overexpression of JAZ9ß rescued the early senescence phenotype of the u2b″ mutant. Furthermore, JA treatment promoted expression of U2B″ that was found to be a direct target of MYC2. Overexpression of MYC2 in the u2b″ mutant resulted in a more pronounced premature senescence than that in wild-type plants. Collectively, our findings reveal that the spliceosomal protein U2B″ fine-tunes leaf senescence by enhancing the expression of JAZ9ß and thereby attenuating JA signaling.

8.
New Phytol ; 240(2): 694-709, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37265004

RESUMO

Leaf senescence is an orderly process regulated by multiple internal factors and diverse environmental stresses including nutrient deficiency. Histone variants are involved in regulating plant growth and development. However, their functions and underlying regulatory mechanisms in leaf senescence remain largely unclear. Here, we found that H2B histone variant HTB4 functions as a negative regulator of leaf senescence. Loss of function of HTB4 led to early leaf senescence phenotypes that were rescued by functional complementation. RNA-seq analysis revealed that several Ib subgroup basic helix-loop-helix (bHLH) transcription factors (TFs) involved in iron (Fe) homeostasis, including bHLH038, bHLH039, bHLH100, and bHLH101, were suppressed in the htb4 mutant, thereby compromising the expressions of FERRIC REDUCTION OXIDASE 2 (FRO2) and IRON-REGULATED TRANSPORTER (IRT1), two important components of the Fe uptake machinery. Chromatin immunoprecipitation-quantitative polymerase chain reaction analysis revealed that HTB4 could bind to the promoter regions of Ib bHLH TFs and enhance their expression by promoting the enrichment of the active mark H3K4me3 near their transcriptional start sites. Moreover, overexpression of Ib bHLH TFs or IRT1 suppressed the premature senescence phenotype of the htb4 mutant. Our work established a signaling pathway, HTB4-bHLH TFs-FRO2/IRT1-Fe homeostasis, which regulates the onset and progression of leaf senescence.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Senescência Vegetal , Homeostase , Proteínas de Membrana Transportadoras/metabolismo , Epigênese Genética , Regulação da Expressão Gênica de Plantas
9.
Plant Physiol ; 189(4): 1943-1960, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35604104

RESUMO

Leaf senescence can be induced by stress or aging, sometimes in a synergistic manner. It is generally acknowledged that the ability to withstand senescence-inducing conditions can provide plants with stress resilience. Although the signaling and transcriptional networks responsible for a delayed senescence phenotype, often referred to as a functional stay-green trait, have been actively investigated, very little is known about the subsequent metabolic adjustments conferring this aptitude to survival. First, using the individually darkened leaf (IDL) experimental setup, we compared IDLs of wild-type (WT) Arabidopsis (Arabidopsis thaliana) to several stay-green contexts, that is IDLs of two functional stay-green mutant lines, oresara1-2 (ore1-2) and an allele of phytochrome-interacting factor 5 (pif5), as well as to leaves from a WT plant entirely darkened (DP). We provide compelling evidence that arginine and ornithine, which accumulate in all stay-green contexts-likely due to the lack of induction of amino acids (AAs) transport-can delay the progression of senescence by fueling the Krebs cycle or the production of polyamines (PAs). Secondly, we show that the conversion of putrescine to spermidine (SPD) is controlled in an age-dependent manner. Thirdly, we demonstrate that SPD represses senescence via interference with ethylene signaling by stabilizing the ETHYLENE BINDING FACTOR1 and 2 (EBF1/2) complex. Taken together, our results identify arginine and ornithine as central metabolites influencing the stress- and age-dependent progression of leaf senescence. We propose that the regulatory loop between the pace of the AA export and the progression of leaf senescence provides the plant with a mechanism to fine-tune the induction of cell death in leaves, which, if triggered unnecessarily, can impede nutrient remobilization and thus plant growth and survival.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Arginina/metabolismo , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Ornitina/genética , Ornitina/metabolismo , Folhas de Planta/metabolismo , Senescência Vegetal , Fatores de Transcrição/metabolismo
10.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36902250

RESUMO

F-box proteins are important components of eukaryotic SCF E3 ubiquitin ligase complexes, which specifically determine protein substrate proteasomal degradation during plant growth and development, as well as biotic and abiotic stress. It has been found that the FBA (F-box associated) protein family is one of the largest subgroups of the widely prevalent F-box family and plays significant roles in plant development and stress response. However, the FBA gene family in poplar has not been systematically studied to date. In this study, a total of 337 F-box candidate genes were discovered based on the fourth-generation genome resequencing of P. trichocarpa. The domain analysis and classification of candidate genes revealed that 74 of these candidate genes belong to the FBA protein family. The poplar F-box genes have undergone multiple gene replication events, particularly in the FBA subfamily, and their evolution can be attributed to genome-wide duplication (WGD) and tandem duplication (TD). In addition, we investigated the P. trichocarpa FBA subfamily using the PlantGenIE database and quantitative real-time PCR (qRT-PCR); the results showed that they are expressed in the cambium, phloem and mature tissues, but rarely expressed in young leaves and flowers. Moreover, they are also widely involved in the drought stress response. At last, we selected and cloned PtrFBA60 for physiological function analysis and found that it played an important role in coping with drought stress. Taken together, the family analysis of FBA genes in P. trichocarpa provides a new opportunity for the identification of P. trichocarpa candidate FBA genes and elucidation of their functions in growth, development and stress response, thus demonstrating their utility in the improvement of P. trichocarpa.


Assuntos
Proteínas F-Box , Família Multigênica , Secas , Genoma de Planta , Genes de Plantas , Proteínas F-Box/genética , Estresse Fisiológico/genética , Filogenia , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas
11.
New Phytol ; 235(2): 550-562, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35396726

RESUMO

Leaf senescence is the final stage of leaf development and is influenced by numerous internal and environmental factors. CLE family peptides are plant-specific peptide hormones that regulate various developmental processes. However, the role of CLE in regulating Arabidopsis leaf senescence remains unclear. Here, we found that CLE42 is a negative regulator of leaf senescence by using a CRISPR/Cas9-produced CLE mutant collection. The cle42 mutant displayed earlier senescence phenotypes, while overexpression of CLE42 delayed age-dependent and dark-induced leaf senescence. Moreover, application of the synthesized 12-amino-acid peptide (CLE42p) also delayed leaf senescence under natural and dark conditions. CLE42 and CLE41/44 displayed functional redundancy in leaf senescence, and the cle41 cle42 cle44 triple mutant displayed more pronounced earlier senescence phenotypes than any single mutant. Analysis of differentially expressed genes obtained by RNA-Seq methodology revealed that the ethylene pathway was suppressed by overexpressing CLE42. Moreover, CLE42 suppressed ethylene biosynthesis and thus promoted the protein accumulation of EBF, which in turn decreased the function of EIN3. Accordingly, mutation of EIN3/EIL1 or overexpression of EBF1 suppressed the earlier senescence phenotypes of the cle42 mutant. Together, our results reveal that the CLE peptide hormone regulates leaf senescence by communicating with the ethylene pathway.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Mutação/genética , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/fisiologia , Senescência Vegetal
12.
Nucleic Acids Res ; 48(D1): D1069-D1075, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31599330

RESUMO

The leaf senescence database (LSD) is a comprehensive resource of senescence-associated genes (SAGs) and their corresponding mutants. Through manual curation and extensive annotation, we updated the LSD to a new version LSD 3.0, which contains 5853 genes and 617 mutants from 68 species. To provide sustainable and reliable services for the plant research community, LSD 3.0 (https://bigd.big.ac.cn/lsd/) has been moved to and maintained by the National Genomics Data Center at Beijing Institute of Genomics, Chinese Academy of Sciences. In the current release, we added some new features: (i) Transcriptome data of leaf senescence in poplar were integrated; (ii) Leaf senescence-associated transcriptome data information in Arabidopsis, rice and soybean were included; (iii) Senescence-differentially expressed small RNAs (Sen-smRNA) in Arabidopsis were identified; (iv) Interaction pairs between Sen-smRNAs and senescence-associated transcription factors (Sen-TF) were established; (v) Senescence phenotypes of 90 natural accessions (ecotypes) and 42 images of ecotypes in Arabidopsis were incorporated; (vi) Mutant seed information of SAGs in rice obtained from Kitbase was integrated; (vii) New options of search engines for ecotypes and transcriptome data were implemented. Together, the updated database bears great utility to continue to provide users with useful resources for studies of leaf senescence.


Assuntos
Envelhecimento/genética , Biologia Computacional/métodos , Bases de Dados Genéticas , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Folhas de Planta/genética , Arabidopsis/genética , Perfilação da Expressão Gênica , Anotação de Sequência Molecular , Mutação , Fenótipo , Navegador
13.
J Integr Plant Biol ; 64(3): 771-786, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34990062

RESUMO

Drought is a critical environmental factor which constrains plant survival and growth. Genetic engineering provides a credible strategy to improve drought tolerance of plants. Here, we generated transgenic poplar lines expressing the isopentenyl transferase gene (IPT) under the driver of PtRD26 promoter (PtRD26pro -IPT). PtRD26 is a senescence and drought-inducible NAC transcription factor. PtRD26pro -IPT plants displayed multiple phenotypes, including improved growth and drought tolerance. Transcriptome analysis revealed that auxin biosynthesis pathway was activated in the PtRD26pro -IPT plants, leading to an increase in auxin contents. Biochemical analysis revealed that ARABIDOPSIS RESPONSE REGULATOR10 (PtARR10), one of the type-B ARR transcription factors in the cytokinin pathway, was induced in PtRD26pro -IPT plants and directly regulated the transcripts of YUCCA4 (PtYUC4) and YUCCA5 (PtYUC5), two enzymes in the auxin biosynthesis pathway. Overexpression of PtYUC4 enhanced drought tolerance, while simultaneous silencing of PtYUC4/5 evidently attenuated the drought tolerance of PtRD26pro -IPT plants. Intriguingly, PtYUC4/5 displayed a conserved thioredoxin reductase activity that is required for drought tolerance by deterring reactive oxygen species accumulation. Our work reveals the molecular basis of cytokinin and auxin interactions in response to environmental stresses, and shed light on the improvement of drought tolerance without a growth penalty in trees by molecular breeding.


Assuntos
Populus , Citocininas/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Populus/metabolismo , Espécies Reativas de Oxigênio/metabolismo
14.
Int J Mol Sci ; 22(22)2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34830215

RESUMO

Gibberellic acid-stimulated Arabidopsis (GASA) proteins, as cysteine-rich peptides (CRPs), play roles in development and reproduction and biotic and abiotic stresses. Although the GASA gene family has been identified in plants, the knowledge about GASAs in Populus euphratica, the woody model plant for studying abiotic stress, remains limited. Here, we referenced the well-sequenced Populus trichocarpa genome, and identified the GASAs in the whole genome of P. euphratica and P. trichocarpa. 21 candidate genes in P. trichocarpa and 19 candidate genes in P. euphratica were identified and categorized into three subfamilies by phylogenetic analysis. Most GASAs with signal peptides were located extracellularly. The GASA genes in Populus have experienced multiple gene duplication events, especially in the subfamily A. The evolution of the subfamily A, with the largest number of members, can be attributed to whole-genome duplication (WGD) and tandem duplication (TD). Collinearity analysis showed that WGD genes played a leading role in the evolution of GASA genes subfamily B. The expression patterns of P. trichocarpa and P. euphratica were investigated using the PlantGenIE database and the real-time quantitative PCR (qRT-PCR), respectively. GASA genes in P. trichocarpa and P. euphratica were mainly expressed in young tissues and organs, and almost rarely expressed in mature leaves. GASA genes in P. euphratica leaves were also widely involved in hormone responses and drought stress responses. GUS activity assay showed that PeuGASA15 was widely present in various organs of the plant, especially in vascular bundles, and was induced by auxin and inhibited by mannitol dramatically. In summary, this present study provides a theoretical foundation for further research on the function of GASA genes in P. euphratica.


Assuntos
Genes de Plantas , Giberelinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/genética , Populus/metabolismo , Transcriptoma , Evolução Molecular , Espaço Extracelular/metabolismo , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Manitol/farmacologia , Filogenia , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/genética , Populus/classificação , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
15.
J Exp Bot ; 71(22): 7270-7285, 2020 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-32822499

RESUMO

Water availability is a main limiting factor for plant growth, development, and distribution throughout the world. Stomatal movement mediated by abscisic acid (ABA) is particularly important for drought adaptation, but the molecular mechanisms in trees are largely unclear. Here, we isolated an ABA-responsive element binding factor, PeABF3, in Populus euphratica. PeABF3 was preferentially expressed in the xylem and young leaves, and was induced by dehydration and ABA treatments. PeABF3 showed transactivation activity and was located in the nucleus. To study its functional mechanism in poplar responsive to drought stress, transgenic triploid white poplars (Populus tomentosa 'YiXianCiZhu B385') overexpressing PeABF3 were generated. PeABF3 overexpression significantly enhanced stomatal sensitivity to exogenous ABA. When subjected to drought stress, PeABF3 overexpression maintained higher photosynthetic activity and promoted cell membrane integrity, resulting in increased water-use efficiency and enhanced drought tolerance compared with wild-type controls. Moreover, a yeast one-hybrid assay and an electrophoretic mobility shift assay revealed that PeABF3 activated the expression of Actin-Depolymerizing Factor-5 (PeADF5) by directly binding to its promoter, promoting actin cytoskeleton remodeling and stomatal closure in poplar under drought stress. Taken together, our results indicate that PeABF3 enhances drought tolerance via promoting ABA-induced stomatal closure by directly regulating PeADF5 expression.


Assuntos
Ácido Abscísico , Populus , Secas , Regulação da Expressão Gênica de Plantas , Estômatos de Plantas/genética , Plantas Geneticamente Modificadas/genética , Populus/genética
16.
Int J Mol Sci ; 21(21)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143308

RESUMO

Leaf senescence is the final stage of leaf development. It is accompanied by the remobilization of nutrients from senescent leaves to developing organs. The occurrence of senescence is the consequence of integrating intrinsic and environmental signals. DNA damage triggered by stresses has been regarded as one of the reasons for senescence. To prevent DNA damage, cells have evolved elaborate DNA repair machinery. The ataxia telangiectasia mutated (ATM) functions as the chief transducer of the double-strand breaks (DSBs) signal. Our previous study suggests that ATM functions in lifespan regulation in Arabidopsis. However, ATM regulatory mechanism on plant longevity remains unclear. Here, we performed chemical mutagenesis to identify the components involved in ATM-mediated longevity and obtained three dominant mutants satmf1~3, suppressor of atm in fertility, displaying delayed senescence and restored fertility in comparison with atm mutant. Molecular cloning and functional analysis of SATMF (suppressor of atm in fertility) will help to understand the underlying regulatory mechanism of ATM in plants, and shed light on developing new treatments for the disease Ataxia-telangiectasia.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Senescência Celular , Fertilidade , Mutação com Perda de Função/genética , Folhas de Planta/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Humanos , Fenótipo , Folhas de Planta/genética , Folhas de Planta/metabolismo
17.
Plant Biotechnol J ; 17(11): 2169-2183, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30977939

RESUMO

In the present study, PeSTZ1, a cysteine-2/histidine-2-type zinc finger transcription factor, was isolated from the desert poplar, Populus euphratica, which serves as a model stress adaptation system for trees. PeSTZ1 was preferentially expressed in the young stems and was significantly up-regulated during chilling and freezing treatments. PeSTZ1 was localized to the nucleus and bound specifically to the PeAPX2 promoter. To examine the potential functions of PeSTZ1, we overexpressed it in poplar 84K hybrids (Populus alba × Populus glandulosa), which are known to be stress-sensitive. Upon exposure to freezing stress, transgenic poplars maintained higher photosynthetic activity and dissipated more excess light energy (in the form of heat) than wild-type poplars. Thus, PeSTZ1 functions as a transcription activator to enhance freezing tolerance without sacrificing growth. Under freezing stress, PeSTZ1 acts upstream of ASCORBATE PEROXIDASE2 (PeAPX2) and directly regulates its expression by binding to its promoter. Activated PeAPX2 promotes cytosolic APX that scavenges reactive oxygen species (ROS) under cold stress. PeSTZ1 may operate in parallel with C-REPEAT-BINDING FACTORS to regulate COLD-REGULATED gene expression. Moreover, PeSTZ1 up-regulation reduces malondialdehyde and ROS accumulation by activating the antioxidant system. Taken together, these results suggested that overexpressing PeSTZ1 in 84K poplar enhances freezing tolerance through the modulation of ROS scavenging via the direct regulation of PeAPX2 expression.


Assuntos
Ascorbato Peroxidases/fisiologia , Congelamento , Proteínas de Plantas/fisiologia , Populus/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/fisiologia , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/fisiologia , Populus/genética , Dedos de Zinco
18.
Plant Biotechnol J ; 16(8): 1514-1528, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29406575

RESUMO

Drought, a primary abiotic stress, seriously affects plant growth and productivity. Stomata play a vital role in regulating gas exchange and drought adaptation. However, limited knowledge exists of the molecular mechanisms underlying stomatal movement in trees. Here, PeCHYR1, a ubiquitin E3 ligase, was isolated from Populus euphratica, a model of stress adaptation in forest trees. PeCHYR1 was preferentially expressed in young leaves and was significantly induced by ABA (abscisic acid) and dehydration treatments. To study the potential biological functions of PeCHYR1, transgenic poplar 84K (Populus alba × Populus glandulosa) plants overexpressing PeCHYR1 were generated. PeCHYR1 overexpression significantly enhanced H2 O2 production and reduced stomatal aperture. Transgenic lines exhibited increased sensitivity to exogenous ABA and greater drought tolerance than that of WT (wild-type) controls. Moreover, up-regulation of PeCHYR1 promoted stomatal closure and decreased transpiration, resulting in strongly elevated WUE (water use efficiency). When exposed to drought stress, transgenic poplar maintained higher photosynthetic activity and biomass accumulation. Taken together, these results suggest that PeCHYR1 plays a crucial role in enhancing drought tolerance via ABA-induced stomatal closure caused by hydrogen peroxide (H2 O2 ) production in transgenic poplar plants.


Assuntos
Ácido Abscísico/farmacologia , Proteínas de Plantas/metabolismo , Estômatos de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Populus/metabolismo , Populus/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Secas , Proteínas de Plantas/genética , Estômatos de Plantas/efeitos dos fármacos , Populus/efeitos dos fármacos , Ubiquitina-Proteína Ligases/genética
19.
J Exp Bot ; 69(22): 5519-5530, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30124931

RESUMO

The hemibiotroph Colletotrichum gloeosporioides and the necrotroph Cytospora chrysosperma cause poplar foliage and stem disease, respectively, resulting in substantial economic losses. In this study, Populus trichocarpa ptc-miR472a was down-regulated in leaves treated with salicylic acid, jasmonic acid (JA) or bacterial flagellin (flg22). Here, ptc-miR472a and a short tandem target mimic (STTM) of miR472a were overexpressed in P. alba × P. glandulosa, and overexpression lines of miR472a and silenced lines of STTM472a were generated. Compared with the STTM472a and wild type lines, lower reactive oxygen species accumulation was detected in miR472a overexpressing plants treated with flg22, C. gloeosporioides or C. chrysosperma. In addition, the miR472a overexpressing lines exhibited the highest susceptibility to the hemibiotroph, C. gloeosporioides, but the highest effective defence response to the necrotroph, C. chrysosperma. The JA/ethylene marker gene ERF1 was rapidly up-regulated in miR472a overexpressing plants. Furthermore, five phased, secondary, small interfering RNAs (phasiRNAs) were confirmed in the miR472a overexpressing and STTM472a lines, triggering phasiRNAs predicted to enhance NBS-LRR silencing. Taken together, our results revealed that ptc-miR472a exerts a key role in plant immunity to C. gloeosporioides and C. chrysosperma by targeting NBS-LRR transcripts. This study provides a new strategy and method in plant breeding to improve plant disease resistance.


Assuntos
Colletotrichum/fisiologia , MicroRNAs/genética , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Populus/genética , Populus/imunologia , Resistência à Doença/genética , MicroRNAs/metabolismo , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Populus/microbiologia , Especificidade da Espécie
20.
New Phytol ; 213(1): 300-313, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27401059

RESUMO

Here, we compared the development of dark- and light-grown Chinese fir (Cunninghamia lanceolata) cotyledons, which synthesize chlorophyll in the dark, representing a different phenomenon from angiosperm model plants. We determined that the grana lamellar membranes were well developed in both chloroplasts and etiochloroplasts. The accumulation of thylakoid membrane protein complexes was similar between chloroplasts and etiochloroplasts. Measurement of chlorophyll fluorescence parameters indicated that photosystem II (PSII) had low photosynthetic activities, whereas the photosystem I (PSI)-driven cyclic electron flow (CEF) rate exceeded the rate of PSII-mediated photon harvesting in etiochloroplasts. Analysis of the protein contents in etiochloroplasts indicated that the light-harvesting complex II remained mostly in its monomeric conformation. The ferredoxin NADP+ oxidoreductase and NADH dehydrogenase-like complexes were relatively abundantly expressed in etiochloroplasts for Chinese fir. Our transcriptome analysis contributes a global expression database for Chinese fir cotyledons, providing background information on the regulatory mechanisms of different genes involved in the development of dark- and light-grown cotyledons. In conclusion, we provide a novel description of the early developmental status of the light-dependent and light-independent photosynthetic apparatuses in gymnosperms.


Assuntos
Cunninghamia/fisiologia , Cunninghamia/efeitos da radiação , Luz , Fotossíntese/efeitos da radiação , Clorofila/metabolismo , Cotilédone/metabolismo , Cotilédone/efeitos da radiação , Cunninghamia/genética , Escuridão , Transporte de Elétrons/efeitos da radiação , Fluorescência , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Complexos Multiproteicos/metabolismo , Fosforilação/efeitos da radiação , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Plastídeos/metabolismo , Plastídeos/ultraestrutura , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação
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