Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.173
Filtrar
1.
Plant Sci ; 286: 28-36, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300139

RESUMO

MYB family genes act as important regulators modulating the response to abiotic stress in plants. However, much less is known about MYB proteins in cotton. Here, we found that a cotton MYB gene, GhMYB73, was induced by NaCl and abscisic acid (ABA). Silencing GhMYB73 expression in cotton increased sensitivity to salt stress. The cotyledon greening rate of Arabidopsis thaliana over-expressing GhMYB73 under NaCl or mannitol treatment was significantly enhanced during the seedling germination stage. What's more, several osmotic stress-induced genes, such as AtNHX1, AtSOS3 and AtP5CS1, were more highly induced in the over-expression lines than in wild type under salt treatment, supporting the hypothesis that GhMYB73 contributes to salinity tolerance by improving osmotic stress resistance. Arabidopsis lines over-expressing GhMYB73 had superior germination and cotyledon greening under ABA treatment, and some abiotic stress-induced genes involved in ABA pathways (AtPYL8, AtABF3, AtRD29B and AtABI5), had increased transcription levels under salt-stress conditions in these lines. Furthermore, we found that GhMYB73 physically interacts with GhPYL8 and AtPYL8, suggesting that GhMYB73 regulates ABA signaling during salinity stress response. Taken together, over-expression of GhMYB73 significantly increases tolerance to salt and ABA stress, indicating that it can potentially be used in transgenic technology approaches to improve cotton salt tolerance.


Assuntos
Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Gossypium/fisiologia , Proteínas de Plantas/genética , Estresse Salino/genética , Fatores de Transcrição/genética , Arabidopsis/genética , Inativação Gênica , Genes myb , Gossypium/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Fatores de Transcrição/metabolismo
2.
BMC Plant Biol ; 19(1): 321, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319815

RESUMO

BACKGROUND: Magnolia wufengensis is a new species of Magnolia L. and has considerable ornamental and economic value due to its unique characteristics. However, because of its characteristic of poor low temperature resistance, M. wufengensis is hardly popularization and application in the north of China. Furthermore, the mechanisms of gene regulation and signaling pathways involved in the cold-stress response remained unclear in this species. In order to solve the above-mentioned problems, we performed de novo transcriptome assembly and compared the gene expression under the natural (25 °C) and cold (4 °C) conditions for M. wufengensis seedlings. RESULTS: More than 46 million high-quality clean reads were produced from six samples (RNA was extracted from the leaves) and were used for performing de novo transcriptome assembly. A total of 59,764 non-redundant unigenes with an average length of 899 bp (N50 = 1,110) were generated. Among these unigenes, 31,038 unigenes exhibited significant sequence similarity to known genes, as determined by BLASTx searches (E-value ≤1.0E-05) against the Nr, SwissProt, String, GO, KEGG, and Cluster of COG databases. Based on a comparative transcriptome analysis, 3,910 unigenes were significantly differentially expressed (false discovery rate [FDR] < 0.05 and |log2FC (CT/CK)| ≥ 1) in the cold-treated samples, and 2,616 and 1,294 unigenes were up- and down-regulated by cold stress, respectively. Analysis of the expression patterns of 16 differentially expressed genes (DEGs) by quantitative real-time RT-PCR (qRT-PCR) confirmed the accuracy of the RNA-Seq results. Gene Ontology and KEGG pathway functional enrichment analyses allowed us to better understand these differentially expressed unigenes. The most significant transcriptomic changes observed under cold stress were related to plant hormone and signal transduction pathways, primary and secondary metabolism, and photosynthesis. In addition, 113 transcription factors, including members of the AP2-EREBP, bHLH, WRKY, MYB, NAC, HSF, and bZIP families, were identified as cold responsive. CONCLUSION: We generated a genome-wide transcript profile of M. wufengensis and a de novo-assembled transcriptome that can be used to analyze genes involved in biological processes. In this study, we provide the first report of transcriptome sequencing of cold-stressed M. wufengensis. Our findings provide important clues not only for understanding the molecular mechanisms of cold stress in plants but also for introducing cold hardiness into M. wufengensis.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Magnolia/genética , Resposta ao Choque Frio , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/fisiologia , Genes de Plantas/genética , Genes de Plantas/fisiologia , Magnolia/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Transdução de Sinais , Transcriptoma
3.
Gene ; 714: 143985, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31330236

RESUMO

In all eukaryotes, the response to heat stress (HS) is dependent on the activity of HS transcription factors (Hsfs). Plants contain a large number of Hsfs, however, only members of the HsfA1 subfamily are considered as master regulators of stress response and thermotolerance. In Solanum lycopersicum, among the four HsfA1 members, only HsfA1a has been proposed to possess a master regulator function. We performed a comparative analysis of HsfA1a, HsfA1b, HsfA1c and HsfA1e at different levels of regulation and function. HsfA1a is constitutively expressed under control and stress conditions, while the other members are induced in specific tissues and stages of HS response. Despite that all members are localized in the nucleus when expressed in protoplasts, only HsfA1a shows a wide range of basal activity on several HS-induced genes. In contrast, HsfA1b, HsfA1c, and HsfA1e show only high activity for specific subsets of genes. Domain swapping mutants between HsfA1a and HsfA1c revealed that the variation in that transcriptional transactivation activity is due to differences in the DNA binding domain (DBD). Specifically, we identified a conserved arginine (R107) residue in the turn of ß3 and ß4 sheet in the C-terminus of the DBD of HsfA1a that is highly conserved in plant HsfA1 proteins, but is replaced by leucine and cysteine in tomato HsfA1c and HsfA1e, respectively. Although not directly involved in DNA interaction, R107 contributes to DNA binding and consequently the activity of HsfA1a. Thus, we demonstrate that this variation in DBD in part explains the functional diversification of tomato HsfA1 members.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Fatores de Transcrição de Choque Térmico/genética , Lycopersicon esculentum/genética , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico/genética , Temperatura Alta , Domínios Proteicos/genética , Protoplastos/fisiologia , Temperatura Ambiente , Termotolerância/genética , Transcrição Genética/genética , Ativação Transcricional/genética
4.
Gene ; 714: 144004, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31351124

RESUMO

Calreticulin (CRT) is calcium binding protein of endoplasmic reticulum (ER) which performs plethora of functions besides it's role as molecular chaperone. Among the three different isoforms of this protein, CRT3 is most closely related to primitive CRT gene of higher plants. Based on their distinct structural and functional organisation, the plant CRTs have been known to contain three different domains: N, P and the C domain. The domain organisation and various biochemical characterstics of plant and animal CRTs are common with the exception of some differences. In plant calreticulin, the important N-glycosylation site(s) are replaced by the glycan chain(s) and several consensus sequences for in vitro phosphorylation by protein kinase CK2 (casein kinase-2), are also present unlike the animal calreticulin. Biotic and abiotic stresses play a significant role in bringing down the crop production. The role of various phytohormones in defense against fungal pathogens is well documented. CRT3 has been reported to play important role in protecting the plants against fungal and bacterial pathogens and in maintaining plant innate immunity. There is remarkable crosstalk between CRT mediated signalling and biotic, abiotic stress, and phytohormone mediated signalling pathways The role of CRT mediated pathway in mitigating biotic and abiotic stress can be further explored in plants so as to strategically modify it for development of stress tolerant plants.


Assuntos
Proteínas de Arabidopsis/genética , Calreticulina/genética , Transdução de Sinais/genética , Estresse Fisiológico/genética , Animais , Regulação da Expressão Gênica de Plantas/genética , Imunidade Vegetal/genética , Isoformas de Proteínas/genética
5.
BMC Plant Biol ; 19(1): 320, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319813

RESUMO

BACKGROUND: Plant cell walls participate in all plant-environment interactions. Maintaining cell wall integrity (CWI) during these interactions is essential. This realization led to increased interest in CWI and resulted in knowledge regarding early perception and signalling mechanisms active during CWI maintenance. By contrast, knowledge regarding processes mediating changes in cell wall metabolism upon CWI impairment is very limited. RESULTS: To identify genes involved and to investigate their contributions to the processes we selected 23 genes with altered expression in response to CWI impairment and characterized the impact of T-DNA insertions in these genes on cell wall composition using Fourier-Transform Infrared Spectroscopy (FTIR) in Arabidopsis thaliana seedlings. Insertions in 14 genes led to cell wall phenotypes detectable by FTIR. A detailed analysis of four genes found that their altered expression upon CWI impairment is dependent on THE1 activity, a key component of CWI maintenance. Phenotypic characterizations of insertion lines suggest that the four genes are required for particular aspects of CWI maintenance, cell wall composition or resistance to Plectosphaerella cucumerina infection in adult plants. CONCLUSION: Taken together, the results implicate the genes in responses to CWI impairment, cell wall metabolism and/or pathogen defence, thus identifying new molecular components and processes relevant for CWI maintenance.


Assuntos
Arabidopsis/genética , Parede Celular/metabolismo , Genes de Plantas/fisiologia , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Ascomicetos , Parede Celular/fisiologia , Resistência à Doença/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Técnicas de Silenciamento de Genes , Interações Hospedeiro-Patógeno , Doenças das Plantas/imunologia , Plântula/metabolismo , Plântula/fisiologia , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Plant Sci ; 285: 165-174, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203881

RESUMO

The TPL/TPR co-repressor is involved in many plant signaling pathways, including those regulating the switch from vegetative to reproductive growth. Here, a TPL homolog (TPL 1-2) was isolated from chrysanthemum. Its product was found to be deposited in the nucleus. The abundance of TPL1-2 transcript varied across the plant, with its highest level being recorded in the stem apex, and its lowest in the root and stem. In the leaf, the abundance of TPL1-2 transcript was highest at dusk in plants exposed to long days, and at dawn in those exposed to short days. Site-directed mutagenesis was used to induce an N176H mutation in TPL1-2. The constitutive expression in Arabidopsis thaliana of the wild type and the mutated alleles of TPL1-2 had a contrasting effect on flowering time, with the mutant transgene expressors flowering later than the wild type transgene expressors. The flowering-related genes FT, TSF, FUL and AP1 were all more strongly transcribed in the mutant transgene expressors than in the wild type transgene expressors.


Assuntos
Chrysanthemum/genética , Flores/crescimento & desenvolvimento , Genes de Plantas/genética , Proteínas de Plantas/genética , Arabidopsis , Chrysanthemum/crescimento & desenvolvimento , Chrysanthemum/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/fisiologia , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Fatores de Tempo , Técnicas do Sistema de Duplo-Híbrido
7.
Plant Cell Rep ; 38(8): 927-936, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31147728

RESUMO

KEY MESSAGE: A new anthocyanin biosynthesis transcription factor PdMYB118, which could be used for the genetic engineering of colorful tree species, was indentified from a red leaf mutant of Populus deltoids. In higher plants, the biosynthesis of anthocyanins is regulated by several classes of transcription factors (TFs), including R2R3-MYB, bHLH and WD-repeat proteins. In this work, we isolated an MYB gene regulating anthocyanin biosynthesis from a red leaf mutant of Populus deltoids, which accumulated more anthocyanins in the leaves and showed higher expression levels of anthocyanin biosynthesis genes than did the wild type. Gene expression analyses of all TFs regulating anthocyanin biosynthesis demonstrated that only a MYB118 homologous gene, PdMYB118, was up-regulated in the mutant compared with the wide type. Subcellular localization analyses in poplar leaf mesophyll protoplasts showed that PdMYB118-YFP fusion protein was specifically located in nucleus. When transiently expressed in poplar leaf protoplasts, PdMYB118 specifically promoted the expression of anthocyanidin biosynthesis genes. Dual-luciferase assays revealed that PdMYB118 can directly activate the promoters of these genes. When overexpressed in Shanxin Yang (P. davidiana × P. bolleana), a hybrid clone commercially grown for landscaping in the northern part of China, transgenic plants overexpressing PdMYB118 produced more anthocyanins in the leaves and turned their color into redness when grown in both greenhouse and field. Consistently, transcripts of some important anthocyanidin biosynthesis genes were significantly increased in the leaves of transgenic plants. All these results indicate that PdMYB118 functions as an essential transcription factor regulating anthocyanin biosynthesis in poplar and could be used for the genetic engineering of colorful tree species.


Assuntos
Antocianinas/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Populus/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Mutação/genética , Folhas de Planta/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Populus/genética , Fatores de Transcrição/genética
8.
BMC Plant Biol ; 19(1): 248, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31185913

RESUMO

BACKGROUND: ZF-HD is a family of genes that play an important role in plant growth, development, some studies have found that after overexpression AtZHD1 in Arabidopsis thaliana, florescence advance, the seeds get bigger and the life span of seeds is prolonged, moreover, ZF-HD genes are also participate in responding to adversity stress. The whole genome of the ZF-HD gene family has been studied in several model plants, such as Arabidopsis thaliana and rice. However, there has been little research on the ZF-HD genes in Tartary buckwheat (Fagopyrum tataricum), which is an important edible and medicinal crop. The recently published whole genome sequence of Tartary buckwheat allows us to study the tissue and expression profiles of the ZF-HD gene family in Tartary buckwheat on a genome-wide basis. RESULTS: In this study, the whole genome and expression profile of the ZF-HD gene family were analyzed for the first time in Tartary buckwheat. We identified 20 FtZF-HD genes and divided them into MIF and ZHD subfamilies according to phylogeny. The ZHD genes were divided into 5 subfamilies. Twenty FtZF-HD genes were distributed on 7 chromosomes, and almost all the genes had no introns. We detected seven pairs of chromosomes with fragment repeats, but no tandem repeats were detected. In different tissues and at different fruit development stages, the FtZF-HD genes obtained by a real-time quantitative PCR analysis showed obvious expression patterns. CONCLUSIONS: In this study, 20 FtZF-HD genes were identified in Tartary buckwheat, and the structures, evolution and expression patterns of the proteins were studied. Our findings provide a valuable basis for further analysis of the biological function of the ZF-HD gene family. Our study also laid a foundation for the improvement of Tartary buckwheat crops.


Assuntos
Fagopyrum/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Família Multigênica , Proteínas de Plantas/genética , Fagopyrum/metabolismo , Perfilação da Expressão Gênica , Filogenia , Proteínas de Plantas/metabolismo
9.
Planta ; 250(2): 603-628, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31139927

RESUMO

MAIN CONCLUSION: Compared with its parents, Brassica hexaploid underwent significant AS changes, which may provide diversified gene expression regulation patterns and could enhance its adaptability during evolution Polyploidization is considered a significant evolution force that promotes species formation. Alternative splicing (AS) plays a crucial role in multiple biological processes during plant growth and development. To explore the effects of allopolyploidization on the AS patterns of genes, a genome-wide AS analysis was performed by RNA-seq in Brassica hexaploid and its parents. In total, we found 7913 (27540 AS events), 14447 (70179 AS events), and 13205 (60804 AS events) AS genes in Brassica rapa, Brassica carinata, and Brassica hexaploid, respectively. A total of 920 new AS genes were discovered in Brassica hexaploid. There were 56 differently spliced genes between Brassica hexaploid and its parents. In addition, most of the alternative 5' splice sites were located 4 bp upstream of the dominant 5' splice sites, and most of the alternative 3' splice sites were located 3 bp downstream of the dominant 3' splice sites in Brassica hexapliod, which was similar to B. carinata. Furthermore, we cloned and sequenced all amplicons from the RT-PCR products of GRP7/8, namely, Bol045859, Bol016025 and Bol02880. The three genes were found to produce AS transcripts in a new way. The AS patterns of genes were diverse between Brassica hexaploid and its parents, including the loss and gain of AS events. Allopolyploidization changed alternative splicing sites of pre-mRNAs in Brassica hexaploid, which brought about alterations in the sequences of transcripts. Our study provided novel insights into the AS patterns of genes in allopolyploid plants, which may provide a reference for the study of polyploidy adaptability.


Assuntos
Processamento Alternativo , Brassica/genética , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Adaptação Fisiológica , Evolução Biológica , Brassica/fisiologia , Brassica rapa/genética , Brassica rapa/fisiologia , Poliploidia
10.
Plant Sci ; 283: 165-176, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31128686

RESUMO

The effect of temperature on the concentrations of anthocyanins and endogenous plant hormones [abscisic acid (ABA), auxin, and cytokinin] were investigated using the detached berries of two related red-skinned cultivars cv. 'Aki Queen' and 'Ruby Roman' of the table grape Vitis labrusca L. × Vitis vinifera L. The total anthocyanin concentration of both cultivars was lower when exposed to high rather than low temperatures after véraison (the onset of ripening). However, the responses to temperature differed between the two cultivars, and anthocyanin accumulation could occur in 'Ruby Roman' at a higher temperature than in 'Aki Queen'. High temperatures increased the expression of VlMybA1-2 and VlMybA1-3, which encode myeloblastosis (MYB)-related transcription factors; however, the expression of the anthocyanin biosynthesis-related structural genes uridine diphosphate-d-glucose: flavonoid 3-O-glucosyltransferase, flavonoid 3'5' hydroxylase, and flavonoid O-methyltransferase at different temperatures did not correspond with that of the expression of MybAs. The concentration of ABA and its derivatives increased under high temperatures, but that of auxin and cytokinin decreased. The observation that high temperatures induced the accumulation of ABA and expression of VlMybA1s but not the expression of anthocyanin biosynthesis-related structural genes implied the operation of a mechanism different from up-regulation of anthocyanin synthesis by VlMybA1s in the temperature response of grape berries.


Assuntos
Ácido Abscísico/biossíntese , Antocianinas/biossíntese , Frutas/metabolismo , Reguladores de Crescimento de Planta/biossíntese , Vitis/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica de Plantas/genética , Temperatura Alta , Redes e Vias Metabólicas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Vitis/genética , Vitis/fisiologia
11.
Plant Mol Biol ; 101(1-2): 1-19, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31062216

RESUMO

KEY MESSAGE: The circadian clock controls many molecular activities, impacting experimental interpretation. We quantify the genome-wide effects of time-of-day on the heat-shock response and the effects of "diurnal bias" in stress experiments. Heat stress has significant adverse effects on plant productivity worldwide. Most experiments examining heat stress are performed during daytime hours, generating a 'diurnal bias' in the pathways and regulatory mechanisms identified. Such bias may confound downstream interpretations and limit our understanding of the full response to heat stress. Here we show that the transcriptional and physiological responses to a sudden heat shock in Arabidopsis are profoundly sensitive to the time of day. We observe that plant tolerance and acclimation to heat shock vary throughout the day and are maximal at dusk. Consistently, over 75% of heat-responsive transcripts show a time of day-dependent response, including many previously characterized heat-response genes. This temporal sensitivity implies a complex interaction between time and temperature where daily variations in basal transcription influence thermotolerance. When we examined these transcriptional responses, we uncovered novel night-response genes and cis-regulatory elements, underpinning new aspects of heat stress responses not previously appreciated. Exploiting this temporal variation can be applied to most environmental responses to understand the underlying network wiring. Therefore, we propose that using time as a perturbagen is an approach that will enhance our understanding of plant regulatory networks and responses to environmental stresses.


Assuntos
Arabidopsis/fisiologia , Relógios Circadianos/genética , Redes Reguladoras de Genes , Genoma de Planta/genética , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico/genética , Aclimatação , Arabidopsis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Temperatura Alta , Plântula/genética , Plântula/fisiologia , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Int J Mol Sci ; 20(9)2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31085987

RESUMO

Sheepgrass (Leymus chinensis (Trin.) Tzvel.) is an economically and ecologically important forage in the grass family. Self-incompatibility (SI) limits its seed production due to the low seed-setting rate after self-pollination. However, investigations into the molecular mechanisms of sheepgrass SI are lacking. Therefore, microscopic observation of pollen germination and pollen tube growth, as well as transcriptomic analyses of pistils after self- and cross-pollination, were performed. The results indicated that pollen tube growth was rapidly inhibited from 10 to 30 min after self-pollination and subsequently stopped but preceded normally after cross-pollination. Time course comparative transcriptomics revealed different transcriptome dynamics between self- and cross-pollination. A pool of SI-related signaling genes and pathways was generated, including genes related to calcium (Ca2+) signaling, protein phosphorylation, plant hormone, reactive oxygen species (ROS), nitric oxide (NO), cytoskeleton, and programmed cell death (PCD). A putative SI response molecular model in sheepgrass was presented. The model shows that SI may trigger a comprehensive calcium- and phytohormone-dominated signaling cascade and activate PCD, which may explain the rapid inhibition of self-pollen tube growth as observed by cytological analyses. These results provided new insight into the molecular mechanisms of sheepgrass (grass family) SI.


Assuntos
Perfilação da Expressão Gênica/métodos , Poaceae/genética , Transcriptoma/genética , Cálcio/metabolismo , Flores/genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polinização/genética , Polinização/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
13.
Int J Mol Sci ; 20(9)2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31086007

RESUMO

Rice (Oryza sativa L.) is one of the most important food crops in the world. In plants, jasmonic acid (JA) plays essential roles in response to biotic and abiotic stresses. As one of the largest transcription factors (TFs), basic region/leucine zipper motif (bZIP) TFs play pivotal roles through the whole life of plant growth. However, the relationship between JA and bZIP TFs were rarely reported, especially in rice. In this study, we found two rice homologues of Arabidopsis VIP1 (VirE2-interacting protein 1), OsbZIP81, and OsbZIP84. OsbZIP81 has at least two alternative transcripts, OsbZIP81.1 and OsbZIP81.2. OsbZIP81.1 and OsbZIP84 are typical bZIP TFs, while OsbZIP81.2 is not. OsbZIP81.1 can directly bind OsPIOX and activate its expression. In OsbZIP81.1 overexpression transgenic rice plant, JA (Jasmonic Acid) and SA (Salicylic acid) were up-regulated, while ABA (Abscisic acid) was down-regulated. Moreover, Agrobacterium, Methyl Jasmonic Acid (MeJA), and PEG6000 can largely induce OsbZIP81. Based on ChIP-Seq and Random DNA Binding Selection Assay (RDSA), we identified a novel cis-element OVRE (Oryza VIP1 response element). Combining ChIP-Seq and RNA-Seq, we obtained 1332 targeted genes that were categorized in biotic and abiotic responses, including α-linolenic acid metabolism and fatty acid degradation. Together, these results suggest that OsbZIP81 may positively regulate JA levels by directly targeting the genes in JA signaling and metabolism pathway in rice.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Oryza/metabolismo , Oxilipinas/metabolismo , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Proteínas de Plantas/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
14.
Plant Cell Physiol ; 60(8): 1734-1746, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31076755

RESUMO

Pentatricopeptide repeat (PPR) proteins play crucial roles in intron splicing, which is important for RNA maturation. Identification of novel PPR protein with the function of intron splicing would help to understand the RNA splicing mechanism. In this study, we identified the maize empty pericarp602 (emp602) mutants, the mature kernels of which showed empty pericarp phenotype. We cloned the Emp602 gene from emp602 mutants and revealed that Emp602 encodes a mitochondrial-localized P-type PPR protein. We further revealed that Emp602 is specific for the cis-splicing of mitochondrial Nad4 intron 1 and intron 3, and mutation of Emp602 led to the loss of mature Nad4 transcripts. The loss of function of Emp602 nearly damaged the assembly and accumulation of complex I and arrested mitochondria formation, which arrested the seed development. The failed assembly of complex I triggers significant upregulation of Aox expression in emp602 mutants. Transcriptome analysis showed that the expression of mitochondrial-related genes, e.g. the genes associated with mitochondrial inner membrane presequence translocase complex and electron carrier activity, were extensively upregulated in emp602 mutant. These results demonstrate that EMP602 functions in the splicing of Nad4 intron 1 and intron 3, and the loss of function of Emp602 arrested maize seed development by disrupting the mitochondria complex I assembly.


Assuntos
Sementes/metabolismo , Zea mays/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Íntrons/genética , Íntrons/fisiologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Processamento de RNA/genética , Processamento de RNA/fisiologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Zea mays/genética , Zea mays/crescimento & desenvolvimento
15.
Plant Cell Physiol ; 60(8): 1702-1721, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31077318

RESUMO

In plants, DNA methylation (i.e. chromatin modification) is important for various biological processes, including growth, development and flowering. Because 'Fuji' apple trees are alternate bearing and have a long ripening period and poor-quality flower buds, we used bud types with diverse flowering capabilities to investigate the epigenetic regulatory mechanisms influencing flower bud formation. We examined the DNA methylation changes and the transcriptional responses in the selected apple bud types. We observed that in the apple genome, approximately 79.5%, 67.4% and 23.7% of the CG, CHG and CHH sequences are methylated, respectively. For each sequence context, differentially methylated regions exhibited distinct methylation patterns among the analyzed apple bud types. Global methylation and transcriptional analyses revealed that nonexpressed genes or genes expressed at low levels were highly methylated in the gene-body regions, suggesting that gene-body methylation is negatively correlated with gene expression. Moreover, genes with methylated promoters were more highly expressed than genes with unmethylated promoters, implying promoter methylation and gene expression are positively correlated. Additionally, flowering-related genes (e.g. SOC1, AP1 and SPLs) and some transcription factor genes (e.g. GATA, bHLH, bZIP and WOX) were highly expressed in spur buds (highest flowering rate), but were associated with low methylation levels in the gene-body regions. Our findings indicate a potential correlation between DNA methylation and gene expression in apple buds with diverse flowering capabilities, suggesting an epigenetic regulatory mechanism influences apple flower bud formation.


Assuntos
Flores/fisiologia , Malus/genética , Malus/fisiologia , Proteínas de Plantas/metabolismo , Análise de Sequência de RNA/métodos , Metilação de DNA/genética , Metilação de DNA/fisiologia , Flores/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
16.
Plant Cell Physiol ; 60(8): 1683-1701, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31077319

RESUMO

Plants are considered to absorb sulfur from their roots in the form of sulfate. In bacteria like Escherichia coli, thiosulfate is a preferred sulfur source. It is converted into cysteine (Cys). This transformation consumes less NADPH and ATP than sulfate assimilation into Cys. In Saccharomyces cerevisiae, thiosulfate promoted growth more than sulfate. In the present study, the availability of thiosulfate, the metabolite transformations and gene expressions it induces were investigated in Arabidopsis and rice as model dicots and monocots, respectively. In Arabidopsis, the thiosulfate-amended plants had lower biomass than those receiving sulfate when sulfur concentrations in the hydroponic medium were above 300 µM. In contrast, rice biomass was similar for plants raised on thiosulfate and sulfate at 300 µM sulfur. Therefore, both plants can use thiosulfate but it is a better sulfur source for rice. In both plants, thiosulfate levels significantly increased in roots following thiosulfate application, indicating that the plants absorbed thiosulfate into their root cells. Thiosulfate is metabolized in plants by a different pathway from that used for sulfate metabolism. Thiosulfate increases plant sulfide and cysteine persulfide levels which means that plants are in a more reduced state with thiosulfate than with sulfate. The microarray analysis of Arabidopsis roots revealed that 13 genes encoding Cys-rich proteins were upregulated more with thiosulfate than with sulfate. These results together with those of the widely targeted metabolomics analysis were used to proposes a thiosulfate assimilation pathway in plants.


Assuntos
Arabidopsis/metabolismo , Oryza/metabolismo , Tiossulfatos/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Metabolômica/métodos , Oryza/crescimento & desenvolvimento , Sulfetos/metabolismo
17.
Plant Cell Physiol ; 60(8): 1761-1777, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31099397

RESUMO

Brassinosteroid (BR) plays an important role in plant development and biotic and abiotic stress tolerance, but its specific function remains largely unknown in wheat (Triticum aestivum L.), preventing its utilization in this important crop. In this study, the function of BR and its underlying cytological role in wheat root development were comprehensively investigated. Our findings demonstrated that BR has a conserved function in regulating root length in wheat, and novel roles in regulating lateral root emergence and root diameter were uncovered. Analyses of BR homologous gene composition and evolutionary divergence demonstrated that the genetic framework of the wheat BR pathway was close to that of rice, but contained highly redundant homologous copies of genes from the subgenome A, B and D. These homologous copies showed active expression and shared a conserved BR response. The expression of wheat DWF4 and glycogen synthase kinase (GSK) genes in Arabidopsis confirmed that multiple homologous copies maintained their conserved function in regulating root development, highlighting their redundant status and indicating that a special challenge exists in wheat gene modification to deal with this high redundancy. However, our results suggested that the hypermorphic effect of T. aestivum GSK (TaGSK) genes with point mutations may be an effective approach to overcome this redundancy in the manipulation of BR signaling in wheat. Our study provides fundamental data uncovering the function of BR in wheat root development, the underlying genetic basis and a possible strategy to manipulate BR signaling in hexaploid wheat.


Assuntos
Brassinosteroides/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Triticum/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Quinases da Glicogênio Sintase/genética , Quinases da Glicogênio Sintase/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/genética
18.
Plant Cell Physiol ; 60(8): 1829-1841, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31119292

RESUMO

Alternative oxidase (AOX) has been reported to be involved in mitochondrial function and redox homeostasis, thus playing an essential role in plant growth as well as stress responses. However, its biological functions in nonseed plants have not been well characterized. Here, we report that AOX participates in plant salt tolerance regulation in moss Physcomitrella patens (P. patens). AOX is highly conserved and localizes to mitochondria in P. patens. We observed that PpAOX rescued the impaired cyanide (CN)-resistant alternative (Alt) respiratory pathway in Arabidopsis thaliana (Arabidopsis) aox1a mutant. PpAOX transcription and Alt respiration were induced upon salt stress in P. patens. Using homologous recombination, we generated PpAOX-overexpressing lines (PpAOX OX). PpAOX OX plants exhibited higher Alt respiration and lower total reactive oxygen species accumulation under salt stress condition. Strikingly, we observed that PpAOX OX plants displayed decreased salt tolerance. Overexpression of PpAOX disturbed redox homeostasis in chloroplasts. Meanwhile, chloroplast structure was adversely affected in PpAOX OX plants in contrast to wild-type (WT) P. patens. We found that photosynthetic activity in PpAOX OX plants was also lower compared with that in WT. Together, our work revealed that AOX participates in plant salt tolerance in P. patens and there is a functional link between mitochondria and chloroplast under challenging conditions.


Assuntos
Bryopsida/metabolismo , Cloroplastos/metabolismo , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Plantas Tolerantes a Sal/metabolismo , Bryopsida/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas Mitocondriais/genética , Oxirredução , Oxirredutases/genética , Proteínas de Plantas/genética , Plantas Tolerantes a Sal/genética
19.
Plant Cell Physiol ; 60(8): 1842-1854, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31135032

RESUMO

Cytokinins are known to regulate various physiological events in plants. Cytokinin signaling is mediated by the phosphorelay system, one of the most ancient mechanisms controlling hormonal pathways in plants. The liverwort Marchantia polymorpha possesses all components necessary for cytokinin signaling; however, whether they respond to cytokinins and how the signaling is fine-tuned remain largely unknown. Here, we report cytokinin function in Marchantia development and organ formation. Our measurement of cytokinin species revealed that cis-zeatin is the most abundant cytokinin in Marchantia. We reduced the endogenous cytokinin level by overexpressing the gene for cytokinin oxidase, MpCKX, which inactivates cytokinins, and generated overexpression and knockout lines for type-A (MpRRA) and type-B (MpRRB) response regulators to manipulate the signaling. The overexpression lines of MpCKX and MpRRA, and the knockout lines of MpRRB, shared phenotypes such as inhibition of gemma cup formation, enhanced rhizoid formation and hyponastic thallus growth. Conversely, the knockout lines of MpRRA produced more gemma cups and exhibited epinastic thallus growth. MpRRA expression was elevated by cytokinin treatment and reduced by knocking out MpRRB, suggesting that MpRRA is upregulated by the MpRRB-mediated cytokinin signaling, which is antagonized by MpRRA. Our findings indicate that when plants moved onto land they already deployed the negative feedback loop of cytokinin signaling, which has an indispensable role in organogenesis.


Assuntos
Citocininas/metabolismo , Marchantia/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Marchantia/genética , Organogênese Vegetal/genética , Organogênese Vegetal/fisiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
20.
Int J Mol Sci ; 20(9)2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035313

RESUMO

Seed storage proteins must be hydrolyzed by proteases to deliver the amino acids essential for embryo growth and development. Several groups of proteases involved in this process have been identified in both the monocot and the dicot species. This review focuses on the implication of proteases during germination in two cereal species, barley and wheat, where proteolytic control during the germination process has considerable economic importance. Formerly, the participation of proteases during grain germination was inferred from reports of proteolytic activities, the expression of individual genes, or the presence of individual proteins and showed a prominent role for papain-like and legumain-like cysteine proteases and for serine carboxypeptidases. Nowadays, the development of new technologies and the release of the genomic sequences of wheat and barley have permitted the application of genome-scale approaches, such as those used in functional genomics and proteomics. Using these approaches, the repertoire of proteases known to be involved in germination has increased and includes members of distinct protease families. The development of novel techniques based on shotgun proteomics, activity-based protein profiling, and comparative and structural genomics will help to achieve a general view of the proteolytic process during germination.


Assuntos
Germinação/fisiologia , Hordeum/enzimologia , Hordeum/fisiologia , Peptídeo Hidrolases/metabolismo , Proteínas de Plantas/metabolismo , Triticum/enzimologia , Triticum/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Germinação/genética , Peptídeo Hidrolases/genética , Proteínas de Plantas/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA