ABSTRACT
WRKYs is a unique family of transcription factors (TFs) in plants, and belongs to the typical multifunctional regulator. It is involved in the regulation of multiple signaling pathways. This type of transcription factor is characterized to contain about 60 highly conservative amino acids as the WRKY domain, and usually also has the Cys2His2 or Cys2His-Cys zinc finger structure. WRKYs can directly bind to the W-box sequence ((T)(T) TGAC (C/T)) in the promoter region of the downstream target gene, and activate or inhibit the transcription of the target genes by interacting with the target protein. They may up-regulate the expression of stress-related genes through integrating signal pathways mediated by abscisic acid (ABA) and reactive oxygen species (ROS), thus playing a vital role in regulating plant response to abiotic stresses. This review summarizes the advances in research on the structure and classification, regulatory approach of WRKYs, and the molecular mechanisms of WRKYs involved in response to drought and salt stresses, and prospects future research directions, with the aim to provide a theoretical support for the genetic improvement of crop in response to abiotic stresses.
Subject(s)
Transcription Factors/genetics , Abscisic Acid , Amino Acids , Droughts , Stress, Physiological/geneticsABSTRACT
Abiotic stresses substantially affect the growth and development of plants. Plants have evolved multiple strategies to cope with the environmental stresses, among which transcription factors play an important role in regulating the tolerance to abiotic stresses. Basic leucine zipper transcription factors (bZIP) are one of the largest gene families. The stability and activity of bZIP transcription factors could be regulated by different post-translational modifications (PTMs) in response to various intracellular or extracellular stresses. This paper introduces the structural feature and classification of bZIP transcription factors, followed by summarizing the PTMs of bZIP transcription factors, such as phosphorylation, ubiquitination and small ubiquitin-like modifier (SUMO) modification, in response to abiotic stresses. In addition, future perspectives were prospected, which may facilitate cultivating excellent stress-resistant crop varieties by regulating the PTMs of bZIP transcription factors.
Subject(s)
Basic-Leucine Zipper Transcription Factors/genetics , Protein Processing, Post-Translational , Phosphorylation , Transcription Factors/genetics , Stress, Physiological/geneticsABSTRACT
The Spt-Ada-Gcn5-acetyltransferase (SAGA) is an ancillary transcription initiation complex which is highly conserved. The ADA1 (alteration/deficiency in activation 1, also called histone H2A functional interactor 1, HFI1) is a subunit in the core module of the SAGA protein complex. ADA1 plays an important role in plant growth and development as well as stress resistance. In this paper, we performed genome-wide identification of banana ADA1 gene family members based on banana genomic data, and analyzed the basic physicochemical properties, evolutionary relationships, selection pressure, promoter cis-acting elements, and its expression profiles under biotic and abiotic stresses. The results showed that there were 10, 6, and 7 family members in Musa acuminata, Musa balbisiana and Musa itinerans. The members were all unstable and hydrophilic proteins, and only contained the conservative SAGA-Tad1 domain. Both MaADA1 and MbADA1 have interactive relationship with Sgf11 (SAGA-associated factor 11) of core module in SAGA. Phylogenetic analysis revealed that banana ADA1 gene family members could be divided into 3 classes. The evolution of ADA1 gene family members was mostly influenced by purifying selection. There were large differences among the gene structure of banana ADA1 gene family members. ADA1 gene family members contained plenty of hormonal elements. MaADA1-1 may play a prominent role in the resistance of banana to cold stress, while MaADA1 may respond to the Panama disease of banana. In conclusion, this study suggested ADA1 gene family members are highly conserved in banana, and may respond to biotic and abiotic stress.
Subject(s)
Musa/genetics , Phylogeny , Fungal Proteins , Cell Nucleus , Histones , Stress, Physiological/geneticsABSTRACT
Germin-like proteins (GLPs) play an important role against various stresses. Vitis vinifera L. genome contains 7 GLPs; many of them are functionally unexplored. However, the computational analysis may provide important new insight into their function. Currently, physicochemical properties, subcellular localization, domain architectures, 3D structures, N-glycosylation & phosphorylation sites, and phylogeney of the VvGLPs were investigated using the latest computational tools. Their functions were predicted using the Search tool for the retrieval of interacting genes/proteins (STRING) and Blast2Go servers. Most of the VvGLPs were extracellular (43%) in nature but also showed periplasmic (29%), plasma membrane (14%), and mitochondrial- or chloroplast-specific (14%) expression. The functional analysis predicted unique enzymatic activities for these proteins including terpene synthase, isoprenoid synthase, lipoxygenase, phosphate permease, receptor kinase, and hydrolases generally mediated by Mn+ cation. VvGLPs showed similarity in the overall structure, shape, and position of the cupin domain. Functionally, VvGLPs control and regulate the production of secondary metabolites to cope with various stresses. Phylogenetically VvGLP1, -3, -4, -5, and VvGLP7 showed greater similarity due to duplication while VvGLP2 and VvGLP6 revealed a distant relationship. Promoter analysis revealed the presence of diverse cis-regulatory elements among which CAAT box, MYB, MYC, unnamed-4 were common to all of them. The analysis will help to utilize VvGLPs and their promoters in future food programs by developing resistant cultivars against various biotic (Erysiphe necator and in Powdery Mildew etc.) and abiotic (Salt, drought, heat, dehydration, etc.) stresses.
As proteínas do tipo germin (GLPs) desempenham um papel importante contra vários estresses. O genoma de Vitis vinifera L. contém 7 GLPs; muitos deles são funcionalmente inexplorados. No entanto, a análise computacional pode fornecer informações importantes sobre sua função. Atualmente, as propriedades físico-químicas, localização subcelular, arquitetura de domínio, estruturas 3D, sítios de N-glicosilação e fosforilação e estudos filogenéticos dos VvGLPs foram conduzidos usando as ferramentas computacionais mais recentes. Suas funções foram previstas usando a ferramenta Search para recuperação de genes/proteínas em interação (STRING) e servidores Blast2Go. A maioria dos VvGLPs são extracelulares (43%) na natureza, mas também mostraram expressão periplasmática (29%), na membrana plasmática (14%) e específica para mitocôndrias ou cloroplastos (14%). A análise funcional previu atividades enzimáticas únicas para essas proteínas, incluindo terpeno sintase, isoprenoide sintase, lipoxigenase, fosfato permease, receptor quinase e hidrolases geralmente mediadas por cátion Mn +. VvGLPs mostraram similaridade na estrutura geral, forma e posição do domínio cupin. Funcionalmente, os VvGLPs controlam e regulam a produção de metabólitos secundários para lidar com vários estresses. Filogeneticamente, VvGLP1, -3, -4, -5 e VvGLP7 mostraram maior similaridade devido à duplicação, enquanto VvGLP2 e VvGLP6 revelaram uma relação distante. A análise do promotor revelou a presença de diversos elementos cis-reguladores, entre os quais CAAT box, MYB, MYC, sem nome-4, sendo comum a todos eles. A análise ajudará a utilizar VvGLPs e seus promotores em programas alimentares futuros, desenvolvendo cultivares resistentes contra vários estresses bióticos (Erysiphe necator e no oídio, etc.) e abióticos (sal, seca, calor, estresse hídrico, etc.).
Subject(s)
Stress, Physiological/genetics , Proteins , Vitis/geneticsABSTRACT
High salt content in soils severely hampers plant growth and crop yields. Many transcription factors in plants play important roles in responding to various stresses, but their molecular mechanisms remain unclear. WRKY transcription factors are one of the largest families of transcription factors in higher plants that are involved in and influence many aspects of plant growth and development. They play important roles in responding to salt stress. The regulation of gene expression by WRKY proteins is mainly achieved by binding to the DNA's specific cis-regulatory elements, the W-box elements (TTGACC). In recent years, there have been many studies revealing the roles and mechanisms of WRKY family members, from model plant Arabidopsis to agricultural crops. This paper reviews the latest research progress on WRKY transcription factors in response to salt stress and discusses the current challenges and future perspectives of WRKY transcription factor research.
Subject(s)
Transcription Factors/metabolism , Plant Proteins/metabolism , Stress, Physiological/genetics , Salt Stress/genetics , Crops, Agricultural/genetics , Gene Expression Regulation, Plant , Phylogeny , Plants, Genetically Modified/geneticsABSTRACT
Galactinol synthase (GolS) genes play important roles in plant response to abiotic stress. In this research, the plant expression vector of soybean GmGolS2-2 gene was constructed and transformed into tobacco to study the drought tolerance of transgenic tobacco. A GmGolS2-2 gene with 975 bp coding sequence was cloned from soybean leaves by reverse transcription-polymerase chain reaction (RT-PCR). GmGolS2-2 was linked to the plant expression vector pRI101 by restriction enzyme sites Nde Ⅰ and EcoR Ⅰ, and transformed into tobacco by leaf disc method. Genomic DNA PCR and real-time PCR showed that three GmGolS2-2 transgenic tobacco plants were obtained. The growth status of GmGolS2-2 transgenic tobacco under drought stress was better than that of wild-type tobacco. After drought stress treatment, the electrolyte leakage and malondialdehyde content of transgenic tobacco were lower than those of wild-type tobacco, but the proline content and soluble sugar content were higher than those of wild-type tobacco. The results of real-time PCR showed that the heterologous expression of GmGolS2-2 increased the expression of stress-related genes NtERD10C and NtAQP1 in transgenic tobacco. The above results indicated that GmGolS2-2 improved drought resistance of transgenic tobacco.
Subject(s)
Drought Resistance , Nicotiana/genetics , Glycine max/genetics , Plant Proteins/metabolism , Plants, Genetically Modified/genetics , Stress, Physiological/genetics , Droughts , Gene Expression Regulation, PlantABSTRACT
Auto-inhibited Ca2+-ATPase (ACA) is one of the Ca2+-ATPase subfamilies that plays an important role in maintaining Ca2+ concentration balance in plant cells. To explore the function and gene expression pattern of the RcACA gene family in castor, bioinformatics analysis was used to identify the members of the RcACA gene family in castor. The basic physical and chemical properties, subcellular location, protein secondary and tertiary structure, conserved domain, conserved motif, gene structure, chromosome location and collinear relationship, as well as the evolutionary characteristics and promoter cis-acting elements were predicted and analyzed. The expression pattern of the RcACA gene under abiotic stress was analyzed by expression (fragments per kilobase of exon model per million mapped fragments, FPKM) in castor transcriptome data. The results showed that 8 RcACA gene family members were identified in castor, acidic proteins located in the plasma membrane. In the secondary structure of all proteins, the α-helix and random coil is more; the RcACA genes were clustered into three categories, and the design of the genes in the same category was similar to the conserved motif. Both of them had four typical domains, RcACA3-RcACA8 had a Ca2+-ATPase N-terminal autoinhibitory domain. The RcACA gene is mostly located on the long arm of the chromosome and has 2 pairs of collinear relationships. There are more light response elements but fewer hormone-induced elements located upstream of the RcACA coding region. Interspecific clustering showed that the evolution of ACA genes among species was conservative. Tissue expression pattern analysis showed that RcACA genes showed apparent tissue expression specificity, and most of the genes showed the highest expression level in male flowers. Expression analysis under abiotic stress showed that RcACA2-RcACA8 were up-regulated under high salt and drought stress, and RcACA1 was up-regulated at 0-24 h under low-temperature stress, indicating that RcACA genes positively responded to abiotic stresses. The above results provide a theoretical basis for exploring the role of the RcACA gene in castor growth, development and stress response.
Subject(s)
Genome, Plant , Stress, Physiological/genetics , Transcriptome , Promoter Regions, Genetic , Phylogeny , Plant Proteins/metabolism , Gene Expression Regulation, PlantABSTRACT
Glutamate receptor-like (GLR) is an important class of Ca2+ channel proteins, playing important roles in plant growth and development as well as in response to biotic and abiotic stresses. In this paper, we performed genome-wide identification of banana GLR gene family based on banana genomic data. Moreover, we analyzed the basic physicochemical properties, gene structure, conserved motifs, promoter cis-acting elements, evolutionary relationships, and used real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) to verify the expression patterns of some GLR family members under low temperature of 4 ℃ and different hormone treatments. The results showed that there were 19 MaGLR family members in Musa acuminata, 16 MbGLR family members in Musa balbisiana and 14 MiGLR family members in Musa itinerans. Most of the members were stable proteins and had signal peptides, all of them had 3-6 transmembrane structures. Prediction of subcellular localization indicated that all of them were localized on the plasma membrane and irregularly distributed on the chromosome. Phylogenetic analysis revealed that banana GLRs could be divided into 3 subclades. The results of promoter cis-acting elements and transcription factor binding site prediction showed that there were multiple hormone- and stress-related response elements and 18 TFBS in banana GLR. RT-qPCR analysis showed that MaGLR1.1 and MaGLR3.5 responded positively to low temperature stress and were significantly expressed in abscisic acid/methyl jasmonate treatments. In conclusion, the results of this study suggest that GLR, a highly conserved family of ion channels, may play an important role in the growth and development process and stress resistance of banana.
Subject(s)
Musa/metabolism , Phylogeny , Abscisic Acid/metabolism , Temperature , Stress, Physiological/genetics , Hormones/metabolism , Gene Expression Regulation, Plant , Plant Proteins/metabolism , Gene Expression ProfilingABSTRACT
Na+/H+ antiporter (NHX) gene subfamily plays an important role in plant response to salt stress. In this study, we identified the NHX gene family members of Chinese cabbage and analyzed the expression patterns of BrNHXs gene in response to abiotic stresses such as high temperature, low temperature, drought and salt stress. The results showed that there were 9 members of the NHX gene family in Chinese cabbage, which were distributed on 6 chromosomes respectively. The number of amino acids was 513-1 154 aa, the relative molecular weight was 56 804.22-127 856.66 kDa, the isoelectric point was 5.35-7.68. Members of BrNHX gene family mainly existed in vacuoles, the gene structure is complete, and the number of exons is 11-22. The secondary structures of the proteins encoded by the NHX gene family in Chinese cabbage had alpha helix, beta turn and random coil, and the alpha helix occurred more frequently. Quantitative real-time PCR (qRT-PCR) analysis showed that the gene family members had different responses to high temperature, low temperature, drought and salt stress, and their expression levels differed significantly in different time periods. BrNHX02 and BrNHX09 had the most significant responses to these four stresses, and their expression levels were significantly up-regulated at 72 h after treatments, which could be used as candidate genes to further verify their functions.
Subject(s)
Genome, Plant , Multigene Family , Stress, Physiological/genetics , Brassica/metabolism , Gene Expression Regulation, Plant , Phylogeny , Plant Proteins/metabolismABSTRACT
SUN gene is a group of key genes regulating plant growth and development. Here, SUN gene families of strawberry were identified from the genome of the diploid Fragaria vesca, and their physicochemical properties, genes structure, evolution and genes expression were also analyzed. Our results showed that there were thirty-one FvSUN genes in F. vesca and the FvSUNs encoded proteins were classified into seven groups, and the members in the same group showed high similarity in gene structures and conservative motifs. The electronic subcellular localization of FvSUNs was mainly in the nucleus. Collinearity analysis showed that the members of FvSUN gene family were mainly expanded by segmental duplication in F. vesca, and Arabidopsis and F. vesca shared twenty-three pairs of orthologous SUN genes. According to the expression pattern in different tissues shown by the transcriptome data of F. vesca, the FvSUNs gene can be divided into three types: (1) expressed in nearly all tissues, (2) hardly expressed in any tissues, and (3) expressed in special tissues. The gene expression pattern of FvSUNs was further verified by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, the seedlings of F. vesca were treated by different abiotic stresses, and the expression level of 31 FvSUNs genes were assayed by qRT-PCR. The expression of most of the tested genes was induced by cold, high salt or drought stress. Our studies may facilitate revealing the biological function and molecular mechanism of SUN genes in strawberry.
Subject(s)
Fragaria/metabolism , Genes, Plant , Stress, Physiological/genetics , Arabidopsis/genetics , Plant Development , Gene Expression Regulation, Plant , Plant Proteins/metabolismABSTRACT
Abstract Transcription factors (TF) are a wide class of genes in plants, and these can regulate the expression of other genes in response to various environmental stresses (biotic and abiotic). In the current study, transcription factor activity in sugarcane was examined during cold stress. Initially, RNA transcript reads of two sugarcane cultivars (ROC22 and GT08-1108) under cold stress were downloaded from SRA NCBI database. The reads were aligned into a reference genome and the differential expression analyses were performed with the R/Bioconductor edgeR package. Based on our analyses in the ROC22 cultivar, 963 TF genes were significantly upregulated under cold stress among a total of 5649 upregulated genes, while 293 TF genes were downregulated among a total of 3,289 downregulated genes. In the GT08-1108 cultivar, 974 TF genes were identified among 5,649 upregulated genes and 283 TF genes were found among 3,289 downregulated genes. Most transcription factors were annotated with GO categories related to protein binding, transcription factor binding, DNA-sequence-specific binding, transcription factor complex, transcription factor activity in RNA polymerase II, the activity of nucleic acid binding transcription factor, transcription corepressor activity, sequence-specific regulatory region, the activity of transcription factor of RNA polymerase II, transcription factor cofactor activity, transcription factor activity from plastid promoter, transcription factor activity from RNA polymerase I promoter, polymerase II and RNA polymerase III. The findings of above results will help to identify differentially expressed transcription factors during cold stress. It also provides a comprehensive analysis of the regulation of the transcription activity of many genes. Therefore, this study provides the molecular basis for improving cold tolerance in sugarcane and other economically important grasses.
Resumo Fatores de transcrição (FT) são uma ampla classe de genes em plantas e podem regular a expressão de outros genes em resposta a vários estresses ambientais (estresses bióticos e abióticos). No presente estudo, a atividade do fator de transcrição na cana-de-açúcar foi examinada durante o estresse pelo frio. Inicialmente, as leituras de transcrição de RNA de duas cultivares de cana-de-açúcar (ROC22 e GT08-1108) sob estresse frio foram baixadas do banco de dados SRA NCBI. As leituras foram alinhadas em um genoma de referência e as análises de expressão diferencial foram realizadas com o pacote R / Bioconductor edgeR. Com base em nossas análises no cultivar ROC22, 963 genes TF foram significativamente regulados positivamente sob estresse pelo frio entre um total de 5.649 genes regulados positivamente, enquanto 293 genes TF foram regulados negativamente entre um total de 3.289 genes regulados negativamente. No cultivar GT08-1108, 974 genes TF foram identificados entre 5.649 genes regulados positivamente e 283 genes TF foram encontrados entre 3.289 genes regulados negativamente. Os fatores de transcrição, em sua maioria, foram anotados com categorias GO relacionadas à ligação de proteína, ligação de fator de transcrição, ligação específica de sequência de DNA, complexo de fator de transcrição, atividade de fator de transcrição em RNA polimerase II, atividade de fator de transcrição de ligação de ácido nucleico, atividade de corepressor de transcrição, sequência específica da região reguladora, atividade do fator de transcrição da RNA polimerase II, atividade do cofator do fator de transcrição, atividade do fator de transcrição do promotor do plastídio, atividade do fator de transcrição do promotor da RNA polimerase I, polimerase II e RNA polimerase III. As descobertas dos resultados acima ajudarão a identificar fatores de transcrição expressos diferencialmente durante o estresse pelo frio. Ele também fornece uma análise abrangente da regulação da atividade de transcrição de muitos genes. Portanto, este estudo fornece base molecular para melhorar a tolerância ao frio em cana-de-açúcar e outras gramíneas economicamente importantes.
Subject(s)
Saccharum/genetics , Saccharum/metabolism , Cold-Shock Response/genetics , Stress, Physiological/genetics , Transcription Factors/genetics , Transcription Factors/metabolism , Cold Temperature , Gene Expression Regulation, Plant , Gene Expression ProfilingABSTRACT
Abstract MicroRNAs (miRNAs) are essential nonprotein-coding genes. In a range of organisms, miRNAs has been reported to play an essential role in regulating gene expressions at post-transcriptional level. They participate in most of the stress responsive processes in plants. Drought is an ultimate abiotic stress that affects the crop production. Therefore understanding drought stress responses are essential to improve the production of agricultural crops. Throughout evolution, plants have developed their own defense systems to cope with the adversities of environmental stresses. Among defensive mechanisms include the regulations of gene expression by miRNAs. Drought stress regulates the expression of some of the functionally conserved miRNAs in different plants. The given properties of miRNAs provide an insight to genetic alterations and enhancing drought resistance in cereal crops. The current review gives a summary to regulatory mechanisms in plants as well as miRNAs response to drought stresses in cereal crops. Some possible approaches and guidelines for the exploitation of drought stress miRNA responses to improve cereal crops are also described.
Resumo MicroRNAs (miRNAs) são genes essenciais não codificadores de proteínas. Em uma variedade de organismos, foi relatado que miRNAs desempenham papel essencial na regulação da expressão gênica em nível pós-transcricional. Eles participam da maioria dos processos responsivos ao estresse nas plantas. A seca é um estresse abiótico final que afeta a produção agrícola. Portanto, compreender as respostas ao estresse da seca é essencial para melhorar a produção de safras agrícolas. Ao longo da evolução, as plantas desenvolveram seus próprios sistemas de defesa para lidar com as adversidades do estresse ambiental. Entre os mecanismos de defesa está a regulação da expressão gênica por miRNAs. O estresse hídrico regula a expressão de alguns dos miRNAs funcionalmente conservados em diferentes plantas. As propriedades dadas dos miRNAs fornecem uma visão das alterações genéticas e aumentam a resistência à seca nas safras de cereais. A revisão atual apresenta um resumo dos mecanismos regulatórios nas plantas, bem como a resposta dos miRNAs ao estresse hídrico nas plantações de cereais. Algumas abordagens e diretrizes possíveis para a exploração das respostas do miRNA ao estresse da seca para melhorar as safras de cereais também são descritas.
Subject(s)
MicroRNAs/genetics , Droughts , Stress, Physiological/genetics , Crops, Agricultural/genetics , Crop ProductionABSTRACT
Abstract Population growth is increasing rapidly around the world, in these consequences we need to produce more foods to full fill the demand of increased population. The world is facing global warming due to urbanizations and industrialization and in this concerns plants exposed continuously to abiotic stresses which is a major cause of crop hammering every year. Abiotic stresses consist of Drought, Salt, Heat, Cold, Oxidative and Metal toxicity which damage the crop yield continuously. Drought and salinity stress severally affected in similar manner to plant and the leading cause of reduction in crop yield. Plants respond to various stimuli under abiotic or biotic stress condition and express certain genes either structural or regulatory genes which maintain the plant integrity. The regulatory genes primarily the transcription factors that exert their activity by binding to certain cis DNA elements and consequently either up regulated or down regulate to target expression. These transcription factors are known as masters regulators because its single transcript regulate more than one gene, in this context the regulon word is fascinating more in compass of transcription factors. Progress has been made to better understand about effect of regulons (AREB/ABF, DREB, MYB, and NAC) under abiotic stresses and a number of regulons reported for stress responsive and used as a better transgenic tool of Arabidopsis and Rice.
Resumo O crescimento populacional está aumentando rapidamente em todo o mundo, e para combater suas consequências precisamos produzir mais alimentos para suprir a demanda do aumento populacional. O mundo está enfrentando o aquecimento global devido à urbanização e industrialização e, nesse caso, plantas expostas continuamente a estresses abióticos, que é uma das principais causas do martelamento das safras todos os anos. Estresses abióticos consistem em seca, sal, calor, frio, oxidação e toxicidade de metais que prejudicam o rendimento da colheita continuamente. A seca e o estresse salino são afetados de maneira diversa pela planta e são a principal causa de redução da produtividade das culturas. As plantas respondem a vários estímulos sob condições de estresse abiótico ou biótico e expressam certos genes estruturais ou regulatórios que mantêm a integridade da planta. Os genes reguladores são principalmente os fatores de transcrição que exercem sua atividade ligando-se a certos elementos cis do DNA e, consequentemente, são regulados para cima ou para baixo para a expressão alvo. Esses fatores de transcrição são conhecidos como reguladores mestres porque sua única transcrição regula mais de um gene; nesse contexto, a palavra regulon é mais fascinante no âmbito dos fatores de transcrição. Progresso foi feito para entender melhor sobre o efeito dos regulons (AREB / ABF, DREB, MYB e NAC) sob estresses abióticos e uma série de regulons relatados como responsivos ao estresse e usados como uma melhor ferramenta transgênica de Arabidopsis e Rice.
Subject(s)
Regulon/genetics , Gene Expression Regulation, Plant , Plant Proteins/metabolism , Stress, Physiological/genetics , Plants, Genetically Modified/genetics , DroughtsABSTRACT
BACKGROUND: Drought stress has significantly hampered agricultural productivity worldwide and can also result in modifications to DNA methylation levels. However, the dynamics of DNA methylation and its association with the changes in gene transcription and alternative splicing (AS) under drought stress are unknown in linseed, which is frequently cultivated in arid and semiarid regions. RESULTS: We analysed AS events and DNA methylation patterns in drought-tolerant (Z141) and drought-sensitive (NY-17) linseed under drought stress (DS) and repeated drought stress (RD) treatments. We found that the number of intron-retention (IR) and alternative 3' splice site (Alt3'SS) events were significantly higher in Z141 and NY-17 under drought stress. We found that the linseed response to the DS treatment was mainly regulated by transcription, while the response to the RD treatment was coregulated by transcription and AS. Whole genome-wide DNA methylation analysis revealed that drought stress caused an increase in the overall methylation level of linseed. Although we did not observe any correlation between differentially methylated genes (DMGs) and differentially spliced genes (DSGs) in this study, we found that the DSGs whose gene body region was hypermethylated in Z141 and hypomethylated in NY-17 were enriched in abiotic stress response Gene Ontology (GO) terms. This finding implies that gene body methylation plays an important role in AS regulation in some specific genes. CONCLUSION: Our study is the first comprehensive genome-wide analysis of the relationship between linseed methylation changes and AS under drought and repeated drought stress. Our study revealed different interaction patterns between differentially expressed genes (DEGs) and DSGs under DS and RD treatments and differences between methylation and AS regulation in drought-tolerant and drought-sensitive linseed varieties. The findings will probably be of interest in the future. Our results provide interesting insights into the association between gene expression, AS, and DNA methylation in linseed under drought stress. Differences in these associations may account for the differences in linseed drought tolerance.
Subject(s)
DNA Methylation , Flax/genetics , Stress, Physiological/genetics , Alternative Splicing/genetics , Gene Expression Regulation, Plant , Gene Expression Profiling , Droughts , TranscriptomeABSTRACT
Sucrose non-fermenting-1-related protein kinase 2 (SnRK2) is a specific Ser/Thr protein kinase in plants. SnRK2 can regulate the expression of downstream genes or transcription factors through phosphorylation of substrates to achieve stress resistance regulation in different tissue parts, and make plants adapt to adverse environment. SnRK2 has a small number of members and a molecular weight of about 40 kDa, and contains a conserved N-terminal kinase domain and a divergent C-terminal regulatory domain, which plays an important role in the expression of enzyme. This review summarized the recent research progresses on the discovery, structure, and classification of SnRK2, and its function in response to various stresses and in regulating growth and development, followed by prospecting the future research direction of SnRK2. This review may provide a reference for genetic improvement of crop stress resistance.
Subject(s)
Abscisic Acid , Arabidopsis Proteins/genetics , Gene Expression Regulation, Plant , Growth and Development , Plants/genetics , Protein Kinases , Protein Serine-Threonine Kinases/genetics , Stress, Physiological/geneticsABSTRACT
With the development of high-throughput sequencing technology, circular RNAs (circRNAs) have gradually become a hotspot in the research on non-coding RNA. CircRNAs are produced by the covalent circularization of a downstream 3' splice donor and an upstream 5' splice acceptor through backsplicing, and they are pervasive in eukaryotic cells. CircRNAs used to be considered byproducts of false splicing, whereas an explosion of related studies in recent years has disproved this misconception. Compared with the rich studies of circRNAs in animals, the study of circRNAs in plants is still in its infancy. In this review, we introduced the discovery of plant circRNAs, the discovery of plant circRNAs, the circularization feature, expression specificity, conservation, and stability of plant circRNAs and expounded the identification tools, main types, and biogenesis mechanisms of circRNAs. Furthermore, we summarized the potential roles of plant circRNAs as microRNA (miRNA) sponges and translation templates and in response to biotic/abiotic stress, and briefed the degradation and localization of plant circRNAs. Finally, we discussed the challenges and proposed the future directions in the research on plant circRNAs.
Subject(s)
Animals , MicroRNAs/metabolism , Organelle Biogenesis , Plants/metabolism , Protein Biosynthesis/physiology , RNA, Circular/metabolism , RNA, Plant/metabolism , Research/trends , Stress, Physiological/geneticsABSTRACT
The responsive patterns of phytochrome gene family members to photoperiod and abiotic stresses were comparatively analyzed and the favorable natural variation sites of these genes were identified. This would help understand the mechanism of phytochrome gene family in photoperiod-regulated growth and development and abiotic stress response. In addition, it may facilitate the molecular marker assisted selection of key traits in foxtail millet. In this study, we used RT-PCR to clone three phytochrome genes SiPHYA, SiPHYB and SiPHYC from ultra-late maturity millet landrace variety 'Maosu'. After primary bioinformatics analysis, we studied the photoperiod control mode and the characteristics of these genes in responding to five abiotic stresses including polyethylene glycol (PEG)-simulated drought, natural drought, abscisic acid (ABA), high temperature and NaCl by fluorescence quantitative PCR. Finally, we detected the mutation sites of the three genes among 160 foxtail millet materials and performed haplotype analysis to determine the genes' functional effect. We found that the cloned cDNA sequences of gene SiPHYA, SiPHYB and SiPHYC were 3 981, 3 953 and 3 764 bp respectively, which contained complete coding regions. Gene SiPHYB and SiPHYC showed closer evolutionary relationship. Photoperiod regulated all of the three genes, but showed more profound effects on diurnal expression pattern of SiPHYB, SiPHYC than that of SiPHYA. Under short-day, when near heading, the expression levels of SiPHYA and SiPHYB were significantly lower than that under long-day, indicating their roles in suppressing heading of foxtail millet under long-day. SiPHYB and SiPHYC were responsive to PEG-simulated drought, natural drought, ABA and high temperature stresses together. SiPHYA and SiPHYB responded differently to salt stress, whereas SiPHYC did not respond to salt stress. Re-sequencing of 160 foxtail millet materials revealed that SiPHYB was highly conservative. Two missense mutations of SiPHYA, such as single nucleotide polymorphism (SNP) 7 034 522C→T and SNP7 036 657G→C, led to delaying heading and increasing plant height. One missense mutation of SiPHYC, such as SNP5 414 823G→T, led to shortening heading under short-day and delaying heading under long-day, as well as increasing plant height and panicle length regardless of photo-thermal conditions. Photoperiod showed different regulatory effects on SiPHYA, SiPHYB and SiPHYC. SiPHYB and SiPHYC jointly responded to various abiotic stresses except for the salt stress. Compared with the reference genotype, mutation genotypes of SiPHYA and SiPHYC delayed heading and increased plant height and panicle length.
Subject(s)
Gene Expression Regulation, Plant , Photoperiod , Phytochrome/metabolism , Plant Proteins/metabolism , Setaria Plant/metabolism , Stress, Physiological/geneticsABSTRACT
WRKY is a superfamily of plant-specific transcription factors, playing a critical regulatory role in multiple biological processes such as plant growth and development, metabolism, and responses to biotic and abiotic stresses. Although WRKY genes have been characterized in a variety of higher plants, little is known about them in eukaryotic algae, which are close to higher plants in evolution. To fully characterize algal WRKY family members, we carried out multiple sequence alignment, phylogenetic analysis, and conserved domain prediction to identify the WRKY genes in the genomes of 30 algal species. A total of 24 WRKY members were identified in Chlorophyta, whereas no WRKY member was detected in Rhodophyta, Glaucophyta, or Bacillariophyta. The 24 WRKY members were classified into Ⅰ, Ⅱa, Ⅱb and R groups, with a conserved heptapeptide domain WRKYGQ(E/A/H/N)K and a zinc finger motif C-X4-5-C-X22-23-H-X-H. Haematococcus pluvialis, a high producer of natural astaxanthin, contained two WRKY members (HaeWRKY-1 and HaeWRKY-2). Furthermore, the coding sequences of HaeWRKY-1 and HaeWRKY-2 genes were cloned and then inserted into prokaryotic expression vector. The recombinant vectors were induced to express in Escherichia coli BL21(DE3) cells and the fusion proteins were purified by Ni-NTA affinity chromatography. HaeWRKY-1 had significantly higher expression level than HaeWRKY-2 in H. pluvialis cultured under normal conditions. High light stress significantly up-regulated the expression of HaeWRKY-1 while down-regulated that of HaeWRKY-2. The promoters of HaeWRKY genes contained multiple cis-elements responsive to light, ethylene, ABA, and stresses. Particularly, the promoter of HaeWRKY-2 contained no W-box specific for WRKY binding. However, the W-box was detected in the promoters of HaeWRKY-1 and the key enzyme genes HaeBKT (β-carotene ketolase) and HaePSY (phytoene synthase) responsible for astaxanthin biosynthesis. Considering these findings and the research progress in the related fields, we hypothesized that the low expression of HaeWRKY-2 under high light stress may lead to the up-regulation of HaeWRKY-1 expression. HaeWRKY-1 may then up-regulate the expression of the key genes (HaeBKT, HaePSY, etc.) for astaxanthin biosynthesis, consequently promoting astaxanthin enrichment in algal cells. The findings provide new insights into further analysis of the regulatory mechanism of astaxanthin biosynthesis and high light stress response of H. pluvialis.
Subject(s)
Eukaryota , Gene Expression Regulation, Plant , Phylogeny , Plant Proteins/metabolism , Plants/metabolism , Stress, Physiological/genetics , Transcription Factors/metabolismABSTRACT
BACKGROUND: Cytokinin signal transduction is mediated by a two-component system (TCS). Two-component systems are utilized in plant responses to hormones as well as to biotic and abiotic environmental stimuli. In plants, response regulatory genes (RRs) are one of the main members of the two-component system (TCS). METHOD: From the aspects of gene structure, evolution mode, expression type, regulatory network and gene function, the evolution process and role of RR genes in the evolution of the cotton genome were analyzed. RESULT: A total of 284 RR genes in four cotton species were identified. Including 1049 orthologous/paralogous gene pairs were identified, most of which were whole genome duplication (WGD). The RR genes promoter elements contain phytohormone responses and abiotic or biotic stress-related cis-elements. Expression analysis showed that RR genes family may be negatively regulate and involved in salt stress and drought stress in plants. Protein regulatory network analysis showed that RR family proteins are involved in regulating the DNA-binding transcription factor activity (COG5641) pathway and HP kinase pathways. VIGS analysis showed that the GhRR7 gene may be in the same regulatory pathway as GhAHP5 and GhPHYB, ultimately negatively regulating cotton drought stress by regulating POD, SOD, CAT, H2O2 and other reactive oxygen removal systems. CONCLUSION: This study is the first to gain insight into RR gene members in cotton. Our research lays the foundation for discovering the genes related to drought and salt tolerance and creating new cotton germplasm materials for drought and salt tolerance.
Subject(s)
Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant/genetics , Phylogeny , Stress, Physiological/genetics , Genes, Regulator , Gossypium/genetics , Droughts , Hydrogen Peroxide/metabolismABSTRACT
BACKGROUND: The internal NAD(P)H dehydrogenase (NDA) gene family was a member of the NAD(P)H dehydrogenase (ND) gene family, mainly involved in the non-phosphorylated respiratory pathways in mitochondria and played crucial roles in response to abiotic stress. METHODS: The whole genome identification, structure analysis and expression pattern of NDA gene family were conducted to analyze the NDA gene family. RESULTS: There were 51, 52, 26, and 24 NDA genes identified in G. hirsutum, G. barbadense, G. arboreum and G. raimondii, respectively. According to the structural characteristics of genes and traits of phylogenetic tree, we divided the NDA gene family into 8 clades. Gene structure analysis showed that the NDA gene family was relatively conservative. The four Gossypium species had good collinearity, and segmental duplication played an important role in the evolution of the NDA gene family. Analysis of cis-elements showed that most GhNDA genes contained cis-elements related to light response and plant hormones (ABA, MeJA and GA). The analysis of the expression patterns of GhNDA genes under different alkaline stress showed that GhNDA genes were actively involved in the response to alkaline stress, possibly through different molecular mechanisms. By analyzing the existing RNA-Seq data after alkaline stress, it was found that an NDA family gene GhNDA32 was expressed, and then theGhNDA32 was silenced by virus-induced gene silencing (VIGS). By observing the phenotype, we found that the wilting degree of silenced plants was much higher than that of the control plant after alkaline treatment, suggesting that GhNDA32 gene was involved in the response to alkaline stress. CONCLUSIONS: In this study, GhNDAs participated in response to alkaline stress, especially NaHCO3 stress. It was of great significance for the future research on the molecular mechanism of NDA gene family in responding to abiotic stresses.