RESUMEN
Sitobion miscanthi, the main species of wheat aphids, is one kind of harmful pest. Chemical insecticides are the important agrochemical products to effectively control wheat aphids. However, the broad application has led to serious resistance of pests to several insecticides, and understanding insecticide resistance mechanisms is critical for integrated pest management. In this study, SmUGGT1, a new uridine diphosphate (UDP)-glycosyltransferase (UGT) gene, was cloned and more strongly expressed in the SM-R (the resistant strain to imidacloprid) than in the SM-S (the susceptible strain to imidacloprid). The increased susceptibility to imidacloprid was observed after silencing SmUGGT1, indicating that it can be related to the resistance to imidacloprid. Subsequently, SmUGGT1 regulated post-transcriptionally in the coding sequences (CDs) by miR-81 was verified and involved in the resistance to imidacloprid in S. miscanthi. This finding is crucial in the roles of UGT involved in insecticide resistance management in pests.
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Áfidos , Resistencia a los Insecticidas , Insecticidas , Neonicotinoides , Nitrocompuestos , Nitrocompuestos/farmacología , Neonicotinoides/farmacología , Insecticidas/farmacología , Animales , Resistencia a los Insecticidas/genética , Áfidos/genética , Áfidos/efectos de los fármacos , Triticum/genética , Triticum/metabolismo , Triticum/parasitología , Triticum/enzimología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
BACKGROUND: Environmental stresses, including high salinity and drought, severely diminish wheat yield and quality globally. The xyloglucan endotransglucosylase/hydrolase (XTH) family represents a class of cell wall-modifying enzymes and plays important roles in plants growth, development and stress adaptation. However, systematic analyses of XTH family genes and their functions under salt and drought stresses have not been undertaken in wheat. RESULTS: In this study, we identified a total of 135 XTH genes in wheat, which were clustered into three evolutionary groups. These TaXTHs were unevenly distributed on 21 chromosomes of wheat with a majority of TaXTHs located on homelogous groups 2, 3 and 7. Gene duplication analysis revealed that segmental and tandem duplication were the main reasons for the expansion of XTH family in wheat. Interaction network predictions indicated that TaXTHs could interact with multiple proteins, including three kinases, one methyltransferase and one gibberellin-regulated protein. The promoters of the TaXTH genes harbored various cis-acting elements related to stress and hormone responses. RNA-seq data analyses showed that some TaXTH genes were induced by salt and drought stresses. Furthermore, we verified that TaXTH17 was induced by abiotic stresses and phytohormone treatments, and demonstrated that TaXTH17 was localized in the secretory pathway and cell wall. Functional analyses conducted in heterologous expression systems and in wheat established that TaXTH17 plays a negative role in plant resistance to salt and drought. CONCLUSIONS: We identified 135 XTH genes in wheat and conducted comprehensive analyses of their phylogenetic relationships, gene structures, conserved motifs, gene duplication events, chromosome locations, interaction networks, cis-acting elements and gene expression patterns. Furthermore, we provided solid evidence supporting the notion that TaXTH17 plays a negative role in plant resistance to salt and drought stresses. Collectively, our results provide valuable insights into understanding wheat XTHs, particularly their involvement in plant stress responses, and establish a foundation for further functional and mechanistic studies of TaXTHs.
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Glicosiltransferasas , Familia de Multigenes , Estrés Fisiológico , Triticum , Triticum/genética , Triticum/enzimología , Triticum/fisiología , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Filogenia , Genes de Plantas , Genoma de Planta , Estudio de Asociación del Genoma Completo , Duplicación de GenRESUMEN
BACKGROUND: Superoxide dismutase (SOD) can greatly scavenge reactive oxygen species (ROS) in plants. SOD activity is highly related to plant stress tolerance that can be improved by overexpression of SOD genes. Identification of SOD activity-related loci and potential candidate genes is essential for improvement of grain quality in wheat breeding. However, the loci and candidate genes for relating SOD in wheat grains are largely unknown. In the present study, grain SOD activities of 309 recombinant inbred lines (RILs) derived from the 'Berkut' × 'Worrakatta' cross were assayed by photoreduction method with nitro-blue tetrazolium (NBT) in four environments. Quantitative trait loci (QTL) of SOD activity were identified using inclusive composite interval mapping (ICIM) with the genotypic data of 50 K single nucleotide polymorphism (SNP) array. RESULTS: Six QTL for SOD activity were mapped on chromosomes 1BL, 4DS, 5AL (2), and 5DL (2), respectively, explaining 2.2 ~ 7.4% of the phenotypic variances. Moreover, QSOD.xjau-1BL, QSOD.xjau-4DS, QSOD.xjau-5 A.1, QSOD.xjau-5 A.2, and QSOD.xjau-5DL.2 identified are likely to be new loci for SOD activity. Four candidate genes TraesCS4D01G059500, TraesCS5A01G371600, TraesCS5D01G299900, TraesCS5D01G343100LC, were identified for QSOD.xjau-4DS, QSOD.xjau-5AL.1, and QSOD.xjau-5DL.1 (2), respectively, including three SOD genes and a gene associated with SOD activity. Based on genetic effect analysis, this can be used to identify desirable alleles and excellent allele variations in wheat cultivars. CONCLUSION: These candidate genes are annotated for promoting SOD production and inhibiting the accumulation of ROS during plant growth. Therefore, lines with high SOD activity identified in this study may be preferred for future wheat breeding.
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Sitios de Carácter Cuantitativo , Superóxido Dismutasa , Triticum , Triticum/genética , Triticum/enzimología , Sitios de Carácter Cuantitativo/genética , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Mapeo Cromosómico , Polimorfismo de Nucleótido Simple , Genes de Plantas , Grano Comestible/genética , FenotipoRESUMEN
Plant fungal parasites manipulate host metabolism to support their own survival. Among the many central metabolic pathways altered during infection, the glyoxylate cycle is frequently upregulated in both fungi and their host plants. Here, we examined the response of the glyoxylate cycle in bread wheat (Triticum aestivum) to infection by the obligate biotrophic fungal pathogen Puccinia striiformis f. sp. tritici (Pst). Gene expression analysis revealed that wheat genes encoding the two unique enzymes of the glyoxylate cycle, isocitrate lyase (TaICL) and malate synthase, diverged in their expression between susceptible and resistant Pst interactions. Focusing on TaICL, we determined that the TaICL B homoeolog is specifically upregulated during early stages of a successful Pst infection. Furthermore, disruption of the B homoeolog alone was sufficient to significantly perturb Pst disease progression. Indeed, Pst infection of the TaICL-B disruption mutant (TaICL-BY400*) was inhibited early during initial penetration, with the TaICL-BY400* line also accumulating high levels of malic acid, citric acid, and aconitic acid. Exogenous application of malic acid or aconitic acid also suppressed Pst infection, with trans-aconitic acid treatment having the most pronounced effect by decreasing fungal biomass 15-fold. Thus, enhanced TaICL-B expression during Pst infection may lower accumulation of malic acid and aconitic acid to promote Pst proliferation. As exogenous application of aconitic acid and malic acid has previously been shown to inhibit other critical pests and pathogens, we propose TaICL as a potential target for disruption in resistance breeding that could have wide-reaching protective benefits for wheat and beyond.
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Glioxilatos , Isocitratoliasa , Malato Sintasa , Enfermedades de las Plantas , Puccinia , Triticum , Triticum/microbiología , Triticum/genética , Triticum/metabolismo , Triticum/enzimología , Isocitratoliasa/metabolismo , Isocitratoliasa/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Glioxilatos/metabolismo , Malato Sintasa/metabolismo , Malato Sintasa/genética , Puccinia/fisiología , Puccinia/patogenicidad , Regulación de la Expresión Génica de las Plantas , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
Seed inoculation with entomopathogenic fungi (EPF) causes plant-mediated effects against arthropod herbivores, but the responses vary among EPF isolates. We used a wheat model system with three isolates representing Beauveria bassiana and Metarhizium spp. causing either negative or positive effects against the aphid Rhopalosiphum padi. Activities of six carbohydrate enzymes increased in plants showing biomass build-up after EPF inoculations. However, only aldolase activity showed positive correlation with R. padi numbers. Plants inoculated with M. robertsii hosted fewest aphids and showed increased activity of superoxide dismutase, implying a defense strategy of resistance towards herbivores. In M. brunneum-inoculated plants, hosting most R. padi, activities of catalase and glutathione reductase were increased suggesting enhanced detoxification responses towards aphids. However, M. brunneum simultaneously increased plant growth indicating that this isolate may cause the plant to tolerate herbivory. EPF seed inoculants may therefore mediate either tolerance or resistance towards biotic stress in plants in an isolate-dependent manner.
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Áfidos , Beauveria , Herbivoria , Triticum , Animales , Triticum/microbiología , Triticum/enzimología , Áfidos/fisiología , Beauveria/fisiología , Metarhizium/fisiología , Defensa de la Planta contra la HerbivoriaRESUMEN
Fusarium head blight (FHB), mainly incited by Fusarium graminearum, has caused great losses in grain yield and quality of wheat globally. Fhb7, a major gene from 7E chromosome of Thinopyrum ponticum, confers broad resistance to multiple Fusarium species in wheat and has recently been cloned and identified as encoding a glutathione S-transferase (GST). However, some recent reports raised doubt about whether GST is the causal gene of Fhb7. To resolve the discrepancy and validate the gene function of GST in wheat, we phenotyped Fhb7 near-isogenic lines (Jimai22-Fhb7 versus Jimai22) and GST overexpressed lines for FHB resistance. Jimai22-Fhb7 showed significantly higher FHB resistance with a lower percentage of symptomatic spikelets, Fusarium-damaged kernels, and deoxynivalenol content than susceptible Jimai22 in three experiments. All the positive GST transgenic lines driven by either the maize ubiquitin promoter or its native promoter with high gene expression in the wheat cultivar 'Fielder' showed high FHB resistance. Only one maize ubiquitin promoter-driven transgenic line showed low GST expression and similar susceptibility to Fielder, suggesting that high GST expression confers Fhb7 resistance to FHB. Knockout of GST in the Jimai22-Fhb7 line using CRISPR-Cas9-based gene editing showed significantly higher FHB susceptibility compared with the nonedited control plants. Therefore, we confirmed GST as the causal gene of Fhb7 for FHB resistance. Considering its major effect on FHB resistance, pyramiding Fhb7 with other quantitative trait loci has a great potential to create highly FHB-resistant wheat cultivars.
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Resistencia a la Enfermedad , Fusarium , Glutatión Transferasa , Enfermedades de las Plantas , Triticum , Fusarium/fisiología , Triticum/microbiología , Triticum/genética , Triticum/enzimología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Resistencia a la Enfermedad/genética , Plantas Modificadas Genéticamente , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poaceae/microbiología , Poaceae/genéticaRESUMEN
BACKGROUND: Class III peroxidases (PODs) perform crucial functions in various developmental processes and responses to biotic and abiotic stresses. However, their roles in wheat seed dormancy (SD) and germination remain elusive. RESULTS: Here, we identified a wheat class III POD gene, named TaPer12-3A, based on transcriptome data and expression analysis. TaPer12-3A showed decreasing and increasing expression trends with SD acquisition and release, respectively. It was highly expressed in wheat seeds and localized in the endoplasmic reticulum and cytoplasm. Germination tests were performed using the transgenic Arabidopsis and rice lines as well as wheat mutant mutagenized with ethyl methane sulfonate (EMS) in Jing 411 (J411) background. These results indicated that TaPer12-3A negatively regulated SD and positively mediated germination. Further studies showed that TaPer12-3A maintained H2O2 homeostasis by scavenging excess H2O2 and participated in the biosynthesis and catabolism pathways of gibberellic acid and abscisic acid to regulate SD and germination. CONCLUSION: These findings not only provide new insights for future functional analysis of TaPer12-3A in regulating wheat SD and germination but also provide a target gene for breeding wheat varieties with high pre-harvest sprouting resistance by gene editing technology.
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Germinación , Latencia en las Plantas , Triticum , Triticum/genética , Triticum/enzimología , Triticum/fisiología , Latencia en las Plantas/genética , Germinación/genética , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/fisiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Peróxido de Hidrógeno/metabolismo , Giberelinas/metabolismo , Arabidopsis/genética , Arabidopsis/fisiología , Peroxidasas/genética , Peroxidasas/metabolismo , Plantas Modificadas Genéticamente , Ácido Abscísico/metabolismo , Genes de PlantasRESUMEN
Mitogen-activated protein kinases (MAPKs) play important roles in plant stress response. As a major member of the MAPK family, MPK3 has been reported to participate in the regulation of chilling stress. However, the regulatory function of wheat (Triticum aestivum ) mitogen-activated protein kinase TaMPK3 in freezing tolerance remains unknown. Dongnongdongmai No.1 (Dn1) is a winter wheat variety with strong freezing tolerance; therefore, it is important to explore the mechanisms underlying this tolerance. In this study, the expression of TaMPK3 in Dn1 was detected under low temperature and hormone treatment. Gene cloning, bioinformatics and subcellular localisation analyses of TaMPK3 in Dn1 were performed. Overexpressed TaMPK3 in Arabidopsis thaliana was obtained, and freezing tolerance phenotype observations, physiological indices and expression levels of ICE-C-repeat binding factor (CBF)-COR -related genes were determined. In addition, the interaction between TaMPK3 and TaICE41 proteins was detected. We found that TaMPK3 expression responds to low temperatures and hormones, and the TaMPK3 protein is localised in the cytoplasm and nucleus. Overexpression of TaMPK3 in Arabidopsis significantly improves freezing tolerance. TaMPK3 interacts with the TaICE41 protein. In conclusion, TaMPK3 is involved in regulating the ICE-CBF-COR cold resistance module through its interaction with TaICE41, thereby improving freezing tolerance in Dn1 wheat.
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Arabidopsis , Congelación , Regulación de la Expresión Génica de las Plantas , Triticum , Arabidopsis/genética , Triticum/genética , Triticum/metabolismo , Triticum/enzimología , Plantas Modificadas Genéticamente/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/genéticaRESUMEN
Although forward-genetics-metabolomics methods such as mGWAS and mQTL have proven effective in providing myriad loci affecting metabolite contents, they are somehow constrained by their respective constitutional flaws such as the hidden population structure for GWAS and insufficient recombinant rate for QTL. Here, the combination of mGWAS and mQTL was performed, conveying an improved statistical power to investigate the flavonoid pathways in common wheat. A total of 941 and 289 loci were, respectively, generated from mGWAS and mQTL, within which 13 of them were co-mapped using both approaches. Subsequently, the mGWAS or mQTL outputs alone and their combination were, respectively, utilized to delineate the metabolic routes. Using this approach, we identified two MYB transcription factor encoding genes and five structural genes, and the flavonoid pathway in wheat was accordingly updated. Moreover, we have discovered some rare-activity-exhibiting flavonoid glycosyl- and methyl-transferases, which may possess unique biological significance, and harnessing these novel catalytic capabilities provides potentially new breeding directions. Collectively, we propose our survey illustrates that the forward-genetics-metabolomics approaches including multiple populations with high density markers could be more frequently applied for delineating metabolic pathways in common wheat, which will ultimately contribute to metabolomics-assisted wheat crop improvement.
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Flavonoides , Sitios de Carácter Cuantitativo , Triticum , Triticum/genética , Triticum/metabolismo , Triticum/enzimología , Flavonoides/metabolismo , Sitios de Carácter Cuantitativo/genética , Mapeo Cromosómico , Metabolómica/métodos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
Multiple genetic factors control tillering, a key agronomy trait for wheat (Triticum aestivum L.) yield. Previously, we reported a dwarf-monoculm mutant (dmc) derived from wheat cultivar Guomai 301, and found that the contents of gibberellic acid 3 (GA3) in the tiller primordia of dmc were significantly higher. Transcriptome analysis indicated that some wheat gibberellin oxidase (TaGAox) genes TaGA20ox-A2, TaGA20ox-B2, TaGA3ox-A2, TaGA20ox-A4, TaGA2ox-A10 and TaGA2ox-B10 were differentially expressed in dmc. Therefore, this study systematically analyzed the roles of gibberellin oxidase genes during wheat tillering. A total of 63 TaGAox genes were identified by whole genome analysis. The TaGAoxs were clustered to four subfamilies, GA20oxs, GA2oxs, GA3oxs and GA7oxs, including seven subgroups based on their protein structures. The promoter regions of TaGAox genes contain a large number of cis-acting elements closely related to hormone, plant growth and development, light, and abiotic stress responses. Segmental duplication events played a major role in TaGAoxs expansion. Compared to Arabidopsis, the gene collinearity degrees of the GAoxs were significantly higher among wheat, rice and maize. TaGAox genes showed tissue-specific expression patterns. The expressions of TaGAox genes (TaGA20ox-B2, TaGA7ox-A1, TaGA2ox10 and TaGA3ox-A2) were significantly affected by exogenous GA3 applications, which also significantly promoted tillering of Guomai 301, but didn't promote dmc. TaGA7ox-A1 overexpression transgenic wheat lines were obtained by Agrobacterium mediated transformation. Genomic PCR and first-generation sequencing demonstrated that the gene was integrated into the wheat genome. Association analysis of TaGA7ox-A1 expression level and tiller number per plant demonstrated that the tillering capacities of some TaGA7ox-A1 transgenic lines were increased. These data demonstrated that some TaGAoxs as well as GA signaling were involved in regulating wheat tillering, but the GA signaling pathway was disturbed in dmc. This study provided valuable clues for functional characterization of GAox genes in wheat.
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Oxigenasas de Función Mixta , Oxidorreductasas , Proteínas de Plantas , Triticum , Agricultura , Agrobacterium/genética , Arabidopsis , Giberelinas/farmacología , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Triticum/clasificación , Triticum/enzimología , Triticum/genética , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Secuencias de Aminoácidos/genética , Regiones Promotoras Genéticas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Perfilación de la Expresión Génica , Reguladores del Crecimiento de las Plantas/farmacologíaRESUMEN
Recombination UVB (sensitivity) like (RuvBL) helicase genes represent a conserved family of genes, which are known to be involved in providing tolerance against abiotic stresses like heat and drought. We identified nine wheat RuvBL genes, one each on nine different chromosomes, belonging to homoeologous groups 2, 3, and 4. The lengths of genes ranged from 1647 to 2197 bp and exhibited synteny with corresponding genes in related species including Ae. tauschii, Z. mays, O. sativa, H. vulgare, and B. distachyon. The gene sequences were associated with regulatory cis-elements and transposable elements. Two genes, namely TaRuvBL1a-4A and TaRuvBL1a-4B, also carried targets for a widely known miRNA, tae-miR164. Gene ontology revealed that these genes were closely associated with ATP-dependent formation of histone acetyltransferase complex. Analysis of the structure and function of RuvBL proteins revealed that the proteins were localized mainly in the cytoplasm. A representative gene, namely TaRuvBL1a-4A, was also shown to be involved in protein-protein interactions with ten other proteins. On the basis of phylogeny, RuvBL proteins were placed in two sub-divisions, namely RuvBL1 and RuvBL2, which were further classified into clusters and sub-clusters. In silico studies suggested that these genes were differentially expressed under heat/drought. The qRT-PCR analysis confirmed that expression of TaRuvBL genes differed among wheat cultivars, which differed in the level of thermotolerance. The present study advances our understanding of the biological role of wheat RuvBL genes and should help in planning future studies on RuvBL genes in wheat including use of RuvBL genes in breeding thermotolerant wheat cultivars.
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Triticum , Triticum/enzimología , Triticum/genética , Estrés Fisiológico , ADN Helicasas/química , ADN Helicasas/genética , ADN Helicasas/metabolismo , Filogenia , ADN Complementario/genética , Cromosomas de las Plantas , Elementos Transponibles de ADN , ARN Mensajero/genéticaRESUMEN
Chlorophyll pigments are used by photosynthetic organisms to facilitate light capture and mediate the conversion of sunlight into chemical energy. Due to the indispensable nature of this pigment and its propensity to form reactive oxygen species, organisms heavily invest in its biosynthesis, recycling, and degradation. One key enzyme implicated in these processes is chlorophyllase, an α/ß hydrolase that hydrolyzes the phytol tail of chlorophyll pigments to produce chlorophyllide molecules. This enzyme was discovered a century ago, but despite its importance to diverse photosynthetic organisms, there are still many missing biochemical details regarding how chlorophyllase functions. Here, we present the 4.46-Å resolution crystal structure of chlorophyllase from Triticum aestivum. This structure reveals the dimeric architecture of chlorophyllase, the arrangement of catalytic residues, an unexpected divalent metal ion-binding site, and a substrate-binding site that can accommodate a diverse range of pigments. Further, this structure exhibits the existence of both intermolecular and intramolecular disulfide bonds. We investigated the importance of these architectural features using enzyme kinetics, mass spectrometry, and thermal shift assays. Through this work, we demonstrated that the oxidation state of the Cys residues is imperative to the activity and stability of chlorophyllase, illuminating a biochemical trigger for responding to environmental stress. Additional bioinformatics analysis of the chlorophyllase enzyme family reveals widespread conservation of key catalytic residues and the identified "redox switch" among other plant chlorophyllase homologs, thus revealing key details regarding the structure-function relationships in chlorophyllase.
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Hidrolasas de Éster Carboxílico , Clorofila , Triticum , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/metabolismo , Clorofila/metabolismo , Disulfuros , Triticum/enzimología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismoRESUMEN
Lead (Pb2+) pollution in the soil sub-ecosystem has been a continuously growing problem due to economic development and ever-increasing anthropogenic activities across the world. In this study, the photosynthetic performance and antioxidant capacity of Triticeae cereals (rye, wheat and triticale) were compared to assess the activities of antioxidants, the degree of oxidative damage, photochemical efficiency and the levels of photosynthetic proteins under Pb stress (0.5 mM, 1 mM and 2 mM Pb (NO3)2). Compared with triticale, Pb treatments imposed severe oxidative damage in rye and wheat. In addition, the highest activity of major antioxidant enzymes (SOD, POD, CAT, and GPX) was also found to be elevated. Triticale accumulated the highest Pb contents in roots. The concentration of mineral ions (Mg, Ca, and K) was also high in its leaves, compared with rye and wheat. Consistently, triticale showed higher photosynthetic activity under Pb stress. Immunoblotting of proteins revealed that rye and wheat have significantly lower levels of D1 (photosystem II subunit A, PsbA) and D2 (photosystem II subunit D, PsbD) proteins, while no obvious decrease was noticed in triticale. The amount of light-harvesting complex II b6 (Lhcb6; CP24) and light-harvesting complex II b5 (Lhcb5; CP26) was significantly increased in rye and wheat. However, the increase in PsbS (photosystem II subunit S) protein only occurred in wheat and triticale exposed to Pb treatment. Taken together, these findings demonstrate that triticale shows higher antioxidant capacity and photosynthetic efficiency than wheat and rye under Pb stress, suggesting that triticale has high tolerance to Pb and could be used as a heavy metal-tolerant plant.
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Plomo , Estrés Oxidativo , Complejo de Proteína del Fotosistema II , Secale , Contaminantes del Suelo , Triticale , Triticum , Ecosistema , Plomo/toxicidad , Secale/efectos de los fármacos , Secale/enzimología , Triticale/efectos de los fármacos , Triticale/enzimología , Triticum/efectos de los fármacos , Triticum/enzimología , Contaminantes del Suelo/toxicidadAsunto(s)
Proteínas de Plantas , Poli(ADP-Ribosa) Polimerasas , Tolerancia a la Sal , Triticum , Adenosina Difosfato Ribosa/metabolismo , Pan , Regulación de la Expresión Génica de las Plantas , Poli(ADP-Ribosa) Polimerasas/química , Poli(ADP-Ribosa) Polimerasas/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo , Triticum/enzimología , Triticum/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Dominios ProteicosRESUMEN
BACKGROUND: TILLING (Targeting Induced Local Lesions in Genomes) is a reverse-genetic strategy that is used to locate an allelic series of induced point mutations in genes of interest. High-throughput TILLING allows the rapid and cost-effective detection of induced point mutations in populations of chemically mutagenized individuals. Grain amylose content is the major constraints for its nutritional quality and have drawn research interest. Identification of allelic variations in genes involved in starch biosynthesis in wheat endosperm is pre-requisite to amenable for nutritional quality improvement. METHODS AND RESULTS: In this study, 44 EMS-induced (M4 generation) mutant lines having variation for amylose content were used for TILLING sequencing. Overall 2098.08 kb of the sequence was analyzed, and the average mutation density was 1/65.56 kb. In analysis, at the high depth score a total of 32 variations were identified including three natural variations, 76% transitions, 10% transversions, and 14% InDels respectively. The substitutions led to intronic variants, UTRs and up-downstream gene variants in Alpha-amylase, TabZIP77.1, TabZIP1 and Myb respectively. In the Myb transcription factor two missense mutations recorded namely Myb_7B c.680G > A and c.1358 T > C led to p.Gly227Asp and p.Met453Thr and c.1390G > A one substitution in Myb_7D led to p.Val464Ile. CONCLUSION: The identified missense substitutions were predicted to affect the protein function; hence they may have a probable role in context to the amylose content in mutants. The mutations ascertained in the current study will help in gene discovery in wheat and identified mutants can be used as genetic resources to improve nutritional quality of wheat.
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Amilosa , Factores de Transcripción , Triticum , alfa-Amilasas , Amilosa/genética , Mutación , Factores de Transcripción/genética , Triticum/enzimología , Triticum/genética , alfa-Amilasas/genéticaRESUMEN
BACKGROUND: Phosphatidylinositol 4 phosphate 5-kinase (PIP5K) plays a key enzyme role in the inositol signal transduction system and has essential functions in plants in terms of growth, development, and stress responses. However, systematic studies on the wheat PIP5K gene family and its relation to male sterility have not been reported yet. RESULTS: Sixty-four TaPIP5K genes were identified. The TaPIP5K genes contained similar gene structures and conserved motifs on the same branches of the evolutionary tree, and their cis-regulatory elements were related to MeJA-responsiveness. Furthermore, 49 pairs of collinearity genes were identified and mainly subjected to purification selection during evolution. Synteny analyses showed that some PIP5K genes in wheat and the other four species shared a relatively conserved evolutionary process. The expression levels of many conservative TaPIP5K genes in HT-ms anthers were significantly lower than that in Normal anthers. In addition, HT-ms anthers have no dehiscence, and levels of OPDA and JA-ILE are significantly lower at the trinucleus stage. CONCLUSION: These results indicate that the PIP5K gene family may be associated with male sterility induced by HT, and the reduction of JA-ILE levels and the abnormal levels of these genes expression may be one reason for the HT-ms anthers having no dehiscence, ultimately leading to the abortion of the anthers.
Asunto(s)
Flores/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Infertilidad Vegetal/genética , Triticum/fisiología , Mapeo Cromosómico , Cromosomas de las Plantas , Fertilidad , Flores/enzimología , Flores/fisiología , Duplicación de Gen , Perfilación de la Expresión Génica , Genes de Plantas , Calor , Familia de Multigenes , Fosfotransferasas (Aceptor de Grupo Alcohol)/fisiología , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Sintenía , Triticum/enzimología , Triticum/genéticaRESUMEN
BACKGROUND: Peroxidase (POD) activity plays an important role in flour-based product quality, which is mainly associated with browning and bleaching effects of flour. Here, we performed a genome-wide association study (GWAS) on POD activity using an association population consisted with 207 wheat world-wide collected varieties. Our study also provide basis for the genetic improvement of flour color-based quality in wheat. RESULTS: Twenty quantitative trait loci (QTLs) were detected associated with POD activity, explaining 5.59-12.67% of phenotypic variation. Superior alleles were positively correlated with POD activity. In addition, two SNPs were successfully developed to KASP (Kompetitive Allele-Specific PCR) markers. Two POD genes, TraesCS2B02G615700 and TraesCS2D02G583000, were aligned near the QTLs flanking genomic regions, but only TraesCS2D02G583000 displayed significant divergent expression levels (P < 0.001) between high and low POD activity varieties in the investigated association population. Therefore, it was deduced to be a candidate gene. The expression level of TraesCS2D02G583000 was assigned as a phenotype for expression GWAS (eGWAS) to screen regulatory elements. In total, 505 significant SNPs on 20 chromosomes (excluding 4D) were detected, and 9 of them located within 1 Mb interval of TraesCS2D02G583000. CONCLUSIONS: To identify genetic loci affecting POD activity in wheat grain, we conducted GWAS on POD activity and the candidate gene TraesCS2D02G583000 expression. Finally, 20 QTLs were detected for POD activity, whereas two QTLs associated SNPs were converted to KASP markers that could be used for marker-assisted breeding. Both cis- and trans-acting elements were revealed by eGWAS of TraesCS2D02G583000 expression. The present study provides genetic loci for improving POD activity across wide genetic backgrounds and largely improved the selection efficiency for breeding in wheat.
Asunto(s)
Genoma de Planta , Peroxidasa/genética , Triticum/enzimología , Triticum/genética , Mapeo Cromosómico , Cromosomas de las Plantas , Harina , Marcadores Genéticos , Estudio de Asociación del Genoma Completo , Peroxidasa/metabolismo , Pigmentación/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter CuantitativoRESUMEN
The production of heterologous proteins is an important procedure for biologists in basic and applied sciences. A variety of cell-based and cell-free protein expression systems are available to achieve this. The expression system must be selected carefully, especially for target proteins that require post-translational modifications. In this study, human Src family kinases were prepared using six different protein expression systems: 293 human embryonic kidney cells, Escherichia coli, and cell-free expression systems derived from rabbit reticulocytes, wheat germ, insect cells, or Escherichia coli. The phosphorylation status of each kinase was analyzed by Phos-tag SDS-PAGE. The kinase activities were also investigated. In the eukaryotic systems, multiple phosphorylated forms of the expressed kinases were observed. In the rabbit reticulocyte lysate system and 293 cells, differences in phosphorylation status between the wild-type and kinase-dead mutants were observed. Whether the expressed kinase was active depended on the properties of both the kinase and each expression system. In the prokaryotic systems, Src and Hck were expressed in autophosphorylated active forms. Clear differences in post-translational phosphorylation among the protein expression systems were revealed. These results provide useful information for preparing functional proteins regulated by phosphorylation.
Asunto(s)
Sistema Libre de Células/enzimología , Regulación de la Expresión Génica/genética , Fosforilación/genética , Familia-src Quinasas/genética , Animales , Escherichia coli/enzimología , Células Germinativas/enzimología , Células HEK293 , Humanos , Insectos/enzimología , Conejos , Reticulocitos/enzimología , Triticum/enzimología , Familia-src Quinasas/metabolismoRESUMEN
Brassinosteroids (BRs) play key roles in diverse plant growth processes through a complex signaling pathway. Components orchestrating the BR signaling pathway include receptors such as kinases, transcription factors, protein kinases and phosphatases. The proper functioning of the receptor kinase BRI1 and the transcription factors BES1/BZR1 depends on their dephosphorylation by type 2A protein phosphatases (PP2A). In this work, we report that an additional phosphatase family, type one protein phosphatases (PP1), contributes to the regulation of the BR signaling pathway. Co-immunoprecipitation and BiFC experiments performed in Arabidopsis plants overexpressing durum wheat TdPP1 showed that TdPP1 interacts with dephosphorylated BES1, but not with the BRI1 receptor. Higher levels of dephosphorylated, active BES1 were observed in these transgenic lines upon BR treatment, indicating that TdPP1 modifies the BR signaling pathway by activating BES1. Moreover, ectopic expression of durum wheat TdPP1 lead to an enhanced growth of primary roots in comparison to wild-type plants in presence of BR. This phenotype corroborates with a down-regulation of the BR-regulated genes CPD and DWF4. These data suggest a role of PP1 in fine-tuning BR-driven responses, most likely via the control of the phosphorylation status of BES1.