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1.
Nat Commun ; 12(1): 3380, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099714

RESUMO

Plant-parasitic nematodes (PPNs) are economically important pests of agricultural crops, and soybean cyst nematode (SCN) in particular is responsible for a large amount of damage to soybean. The need for new solutions for controlling SCN is becoming increasingly urgent, due to the slow decline in effectiveness of the widely used native soybean resistance derived from genetic line PI 88788. Thus, developing transgenic traits for controlling SCN is of great interest. Here, we report a Bacillus thuringiensis delta-endotoxin, Cry14Ab, that controls SCN in transgenic soybean. Experiments in C. elegans suggest the mechanism by which the protein controls nematodes involves damaging the intestine, similar to the mechanism of Cry proteins used to control insects. Plants expressing Cry14Ab show a significant reduction in cyst numbers compared to control plants 30 days after infestation. Field trials also show a reduction in SCN egg counts compared with control plants, demonstrating that this protein has excellent potential to control PPNs in soybean.


Assuntos
Toxinas de Bacillus thuringiensis/genética , Produtos Agrícolas/parasitologia , Resistência à Doença/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Soja/parasitologia , Tylenchoidea/patogenicidade , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis/metabolismo , Bioensaio , Caenorhabditis elegans , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Endotoxinas/metabolismo , Feminino , Engenharia Genética , Proteínas Hemolisinas/metabolismo , Melhoramento Vegetal/métodos , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/parasitologia , Soja/genética , Soja/metabolismo , Tylenchoidea/isolamento & purificação
2.
Mol Plant Pathol ; 22(3): 373-381, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33484494

RESUMO

Phytophthora sojae is an important model species for oomycete functional genomics research. Recently, a CRISPR/Cas9-mediated genome-editing technology has been successfully established in P. sojae, which has been rapidly and widely applied in oomycete research. However, there is an emerging consensus in the biological community that a complete functional gene research system is needed such as developed in the investigations in functional complementation carried out in this study. We report the development of an in situ complementation method for accurate restoration of the mutated gene. We targeted a regulatory B-subunit of protein phosphatase 2A (PsPP2Ab1) to verify this knockout and subsequent complementation system. We found that the deletion of PsPP2Ab1 in P. sojae leads to severe defects in vegetative hyphal growth, soybean infection, and loss of the ability to produce sporangia. Subsequently, the reintroduction of PsPP2Ab1 into the knockout mutant remedied all of the deficiencies. This study demonstrates the successful implementation of an in situ complementation system by CRISPR/Cas9, which will greatly accelerate functional genomics research of oomycetes in the post-genomic era.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Phytophthora/genética , Doenças das Plantas/parasitologia , Soja/parasitologia , Técnicas de Inativação de Genes , Mutação
3.
PLoS One ; 16(1): e0244305, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33444331

RESUMO

The Glycine max xyloglucan endotransglycosylase/hydrolase (EC 2.4.1.207), GmXTH43, has been identified through RNA sequencing of RNA isolated through laser microdissection of Heterodera glycines-parasitized root cells (syncytia) undergoing the process of defense. Experiments reveal that genetically increasing XTH43 transcript abundance in the H. glycines-susceptible genotype G. max[Williams 82/PI 518671] decreases parasitism. Experiments presented here show decreasing XTH43 transcript abundance through RNA interference (RNAi) in the H. glycines-resistant G. max[Peking/PI 548402] increases susceptibility, but it is unclear what role XTH43 performs. The experiments presented here show XTH43 overexpression decreases the relative length of xyloglucan (XyG) chains, however, there is an increase in the amount of those shorter chains. In contrast, XTH43 RNAi increases XyG chain length. The experiments show that XTH43 has the capability to function, when increased in its expression, to limit XyG chain extension. This outcome would likely impair the ability of the cell wall to expand. Consequently, XTH43 could provide an enzymatically-driven capability to the cell that would allow it to limit the ability of parasitic nematodes like H. glycines to develop a feeding structure that, otherwise, would facilitate parasitism. The experiments presented here provide experimentally-based proof that XTHs can function in ways that could be viewed as being able to limit the expansion of the cell wall.


Assuntos
Glucanos/metabolismo , Glicosiltransferases/metabolismo , Proteínas de Plantas/metabolismo , Soja/parasitologia , Tylenchida/fisiologia , Xilanos/metabolismo , Animais , Cromatografia em Gel , Feminino , Genótipo , Glucanos/química , Glicosiltransferases/antagonistas & inibidores , Glicosiltransferases/genética , Interações Hospedeiro-Parasita , Peso Molecular , Raízes de Plantas/parasitologia , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Análise de Componente Principal , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Soja/enzimologia , Soja/genética , Xilanos/química
4.
PLoS One ; 15(10): e0239910, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33002075

RESUMO

Transgenic cotton expressing Cry51Aa2.834_16 Bt toxin (hereafter referred to as MON 88702) has the potential to be an important tool for pest management due to its unique activity against tobacco thrips, Frankliniella fusca. Unlike other Bt toxins targeting lepidopteran cotton pests, MON 88702 does not cause direct mortality but has an antixenotic effect that suppresses F. fusca oviposition. Previous work has shown neonicotinoid seed treated (NST) crops have similar behavioral effects on thrips. This study used non-choice and common garden experiments to examine how the presence of MON 88702 cotton and soybean (another F. fusca host) with and without NSTs might alter F. fusca infestation distributions. In a no-choice environment, significant larval establishment differences were observed, with untreated soybean plants becoming most heavily infested. In choice experiments, plants expressing MON 88702 or were neonicotinoid treated had significantly lower larval establishment. Larval density decreased as dispersal distance increased, suggesting reproductive decisions were negatively related to distance from the release point. Understanding how F. fusca responds to MON 88702 in an environment where adults can choose among multiple host plants will provide valuable context for projections regarding design of MON 88702 resistance refuges. Reduced larval establishment on NST cotton and soybean suggests that area-wide use of NSTs could reduce the number of susceptible F. fusca generated in unstructured crop refuges for MON 88702. These results also suggest that although the presence of NST MON 88702 could suppress reproduction and resistance selection, over time this benefit could erode resulting in increased larval establishment on NST cotton and soybean due to increased frequency of neonicotinoid resistant F. fusca populations.


Assuntos
Gossypium/parasitologia , Inseticidas/farmacologia , Neonicotinoides/farmacologia , Doenças das Plantas/prevenção & controle , Tisanópteros/efeitos dos fármacos , Animais , Bacillus thuringiensis/genética , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Gossypium/genética , Oviposição/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Sementes/parasitologia , Soja/genética , Soja/parasitologia , Tisanópteros/patogenicidade , Tisanópteros/fisiologia
5.
Proc Natl Acad Sci U S A ; 117(37): 23125-23130, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32868415

RESUMO

Many plants use environmental cues, including seasonal changes of day length (photoperiod), to control their flowering time. Under inductive conditions, FLOWERING LOCUS T (FT) protein is synthesized in leaves, and FT protein is a mobile signal, which is able to travel to the shoot apex to induce flowering. Dodders (Cuscuta, Convolvulaceae) are root- and leafless plants that parasitize a large number of autotrophic plant species with varying flowering time. Remarkably, some dodder species, e.g., Cuscuta australis, are able to synchronize their flowering with the flowering of their hosts. Detailed sequence inspection and expression analysis indicated that the FT gene in dodder C. australis very likely does not function in activating flowering. Using soybean host plants cultivated under inductive and noninductive photoperiod conditions and soybean and tobacco host plants, in which FT was overexpressed and knocked out, respectively, we show that FT-induced flowering of the host is likely required for both host and parasite flowering. Biochemical analysis revealed that host-synthesized FT signals are able to move into dodder stems, where they physically interact with a dodder FD transcription factor to activate dodder flowering. This study demonstrates that FTs can function as an important interplant flowering signal in host-dodder interactions. The unique means of flowering regulation of dodder illustrates how regressive evolution, commonly found in parasites, may facilitate the physiological synchronization of parasite and host, here allowing the C. australis parasite to time reproduction exactly with that of their hosts, likely optimizing parasite fitness.


Assuntos
Cuscuta/fisiologia , Cuscuta/parasitologia , Flores/fisiologia , Flores/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Parasitos/fisiologia , Animais , Regulação da Expressão Gênica de Plantas/fisiologia , Folhas de Planta/parasitologia , Folhas de Planta/fisiologia , Soja/parasitologia , Soja/fisiologia , Tabaco/parasitologia , Tabaco/fisiologia , Fatores de Transcrição/metabolismo
6.
Mol Plant Microbe Interact ; 33(11): 1340-1352, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32757880

RESUMO

DNA methylation is a widespread epigenetic mark that affects gene expression and transposon mobility during plant development and stress responses. However, the role of DNA methylation in regulating the expression of microRNA (miRNA) genes remains largely unexplored. Here, we analyzed DNA methylation changes of miRNA genes using a pair of soybean (Glycine max) near-isogenic lines (NILs) differing in their response to soybean cyst nematode (SCN; Heterodera glycines). Differences in global DNA methylation levels over miRNA genes in response to SCN infection were observed between the isogenic lines. miRNA genes with significant changes in DNA methylation levels in the promoter and primary transcript-coding regions were detected in both lines. In the susceptible isogenic line (NIL-S), 82 differentially methylated miRNAs were identified in response to SCN infection whereas, in the resistant isogenic line (NIL-R), only 16 differentially methylated miRNAs were identified. Interestingly, gma-miR5032, gma-miR5043, gma-miR1520b, and gma-2107-ch16 showed opposite methylation patterns in the isogenic lines. In addition, the miRNA paralogs gma-miR5770a and gma-miR5770b showed hypermethylation and hypomethylation in NIL-S and NIL-R, respectively. Gene expression quantification of gma-miR5032, gma-miR5043, gma-miR1520b, and gma-miR5770a/b and their confirmed targets indicated a role of DNA methylation in regulating miRNA expression and, thus, their targets upon SCN infection. Furthermore, overexpression of these four miRNAs in NIL-S using transgenic hairy root system enhanced plant resistance to SCN to various degrees with a key role observed for miR5032. Together, our results provide new insights into the role of epigenetic mechanisms in controlling miRNA regulatory function during SCN-soybean interactions.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Metilação de DNA , Interações Hospedeiro-Parasita/genética , MicroRNAs , Doenças das Plantas/parasitologia , Soja/genética , Tylenchoidea , Animais , Epigênese Genética , MicroRNAs/genética , Doenças das Plantas/genética , Soja/parasitologia
7.
PLoS One ; 15(8): e0237194, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760135

RESUMO

We aimed to profile the metabolism of soybean roots that were infected with soybean cyst nematodes and treated with Bacillus simplex to identify metabolic differences that may explain nematode resistance. Compared with control soybean roots, B. simplex-treated soybean roots contained lower levels of glucose, fructose, sucrose, and trehalose, which reduced the nematodes' food source. Furthermore, treatment with B. simplex led to higher levels of melibiose, gluconic acid, lactic acid, phytosphingosine, and noradrenaline in soybean roots, which promoted nematocidal activity. The levels of oxoproline, maltose, and galactose were lowered after B. simplex treatment, which improved disease resistance. Collectively, this study provides insight into the metabolic alterations induced by B. simplex treatment, which affects the interactions with soybean cyst nematodes.


Assuntos
Bacillus/patogenicidade , Resistência à Doença , Metaboloma , Nematoides/patogenicidade , Soja/parasitologia , Animais , Metabolismo dos Carboidratos , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/parasitologia , Soja/metabolismo , Soja/microbiologia
8.
Chemosphere ; 259: 127499, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32629314

RESUMO

Soybean looper (SBL), Chrysodeixis includens (Walker), is an economically important soybean and cotton pest in Brazil. Here, we selected an SBL strain resistant to teflubenzuron using F2 screening, estimated the resistance allele frequency, characterized the inheritance of resistance, investigated fitness costs, evaluated patterns of cross-resistance, and determined the magnitude of resistance. The teflubenzuron-resistant strain (Teflu-R) was selected from field-collected populations with an estimated allele frequency of 0.1700. Estimated LC50 values were 0.010 and 363.61 µg a.i. cm-2 for the susceptible (Sus) and Teflu-R strains, respectively, representing a 36,361-fold resistance ratio (RR). The LC50 values of reciprocal crosses were 1.02 and 0.59 µg a.i. cm-2, suggesting that resistance is autosomally inherited. The low survival of reciprocal crosses (16 and 20%) on teflubenzuron-sprayed leaves indicates incomplete recessive resistance. The number of segregations influencing resistance was 2.72, suggesting a polygenic effect. The Teflu-R strain showed longer development periods as well as lower survival and population growth than the Sus strain, revealing fitness costs. The Teflu-R strain also showed high cross-resistancesto other chitin inhibitor insecticides, such as novaluron (RR = 6147-fold) and lufenuron (RR = 953-fold), but low cross-resistance to methoxyfenozide, flubendiamide, and indoxacarb (RR < 3.45-fold). On discriminatory concentrations of teflubenzuron and novaluron, populations of SBL showed survival rates from 15 to 52%, indicating field resistance to these insecticides. Our findings indicated that resistance to teflubenzuron in SBL is autosomal, recessive, polygenic, and associated with fitness cost. We also found a high cross-resistance to other benzoylphenylureas and a high frequency of resistance to this mode-of-action in SBL in Brazil.


Assuntos
Quitina/antagonistas & inibidores , Resistência a Inseticidas , Inseticidas , Mariposas/efeitos dos fármacos , Soja/parasitologia , Animais , Benzamidas/farmacologia , Brasil , Quitina/biossíntese , Quitina/farmacologia , Hidrazinas/farmacologia , Inseticidas/farmacologia , Hormônios Juvenis/farmacologia , Larva/efeitos dos fármacos , Lepidópteros/efeitos dos fármacos , Compostos de Fenilureia/farmacologia , Doenças das Plantas/parasitologia , Soja/efeitos dos fármacos , Sulfonas/farmacologia
9.
PLoS One ; 15(7): e0235089, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32673346

RESUMO

Soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is one of the most devastating pathogens affecting soybean production in the U.S. and worldwide. The use of SCN-resistant soybean cultivars is one of the most affordable strategies to cope with SCN infestation. Because of the limited sources of SCN resistance and changes in SCN virulence phenotypes, host resistance in current cultivars has increasingly been overcome by the pathogen. Host tolerance has been recognized as an additional tool to manage the SCN. The objectives of this study were to conduct a genome-wide association study (GWAS), to identify single nucleotide polymorphism (SNP) markers, and to perform a genomic selection (GS) study for SCN tolerance in soybean based on reduction in biomass. A total of 234 soybean genotypes (lines) were evaluated for their tolerance to SCN in greenhouse using four replicates. The tolerance index (TI = 100 × Biomass of a line in SCN infested / Biomass of the line without SCN) was used as phenotypic data of SCN tolerance. GWAS was conducted using a total of 3,782 high quality SNPs. GS was performed based upon the whole set of SNPs and the GWAS-derived SNPs, respectively. Results showed that (1) a large variation in soybean TI to SCN infection among the soybean genotypes was identified; (2) a total of 35, 21, and 6 SNPs were found to be associated with SCN tolerance using the models SMR, GLM (PCA), and MLM (PCA+K) with 6 SNPs overlapping between models; (3) GS accuracy was SNP set-, model-, and training population size-dependent; and (4) genes around Glyma.06G134900, Glyma.15G097500.1, Glyma.15G100900.3, Glyma.15G105400, Glyma.15G107200, and Glyma.19G121200.1 (Table 4). Glyma.06G134900, Glyma.15G097500.1, Glyma.15G100900.3, Glyma.15G105400, and Glyma.19G121200.1 are best candidates. To the best of our knowledge, this is the first report highlighting SNP markers associated with tolerance index based on biomass reduction under SCN infestation in soybean. This research opens a new approach to use SCN tolerance in soybean breeding and the SNP markers will provide a tool for breeders to select for SCN tolerance.


Assuntos
Resistência à Doença/genética , Estudo de Associação Genômica Ampla , Soja/genética , Tylenchoidea/patogenicidade , Animais , Biomassa , Genes de Plantas , Marcadores Genéticos , Genoma de Planta , Doenças das Plantas/genética , Polimorfismo de Nucleotídeo Único , Infecções por Secernentea/prevenção & controle , Soja/parasitologia
10.
PLoS One ; 15(4): e0231098, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32315304

RESUMO

Trichogramma leucaniae is believed to be an efficient biological control agent for controlling the soybean pod borer [SPB; Leguminivora glycinivorella]. The large eggs of Chinese oak silkworm, Antheraea pernyi, are one of the best alternative host for mass production of Trichogramma. However, they are considered poor host for the growth and development of T. leucaniae. Here, we determine the feasibility of successive rearings of T. leucaniae on the large eggs for eight generations and evaluated their capacity of parasitizing SPB eggs of different ages. In the first four generations, the suitability of T. leucaniae reared on large eggs exhibited a significant increasing tendency and then decreased with the successive generations thereafter. The percentage of parasitized eggs and number of emerged adults per egg were increased from 40.0% and 10.8 adults/egg in F1 generation to 86.7% and 36.4 adults/egg in F4 generation respectively. In addition, T. leucaniae reared on A. pernyi for four generations significantly parasitized more SPB eggs regardless of egg age compared with those reared on Corcyra cephalonica eggs. These results provided useful information on the feasibility of mass production of T. leucaniae by reared for successive generations on A. pernyi large eggs.


Assuntos
Bombyx/parasitologia , Ovos/parasitologia , Himenópteros/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Animais , Feminino , Interações Hospedeiro-Parasita , Humanos , Himenópteros/patogenicidade , Masculino , Óvulo/parasitologia , Soja/parasitologia
11.
Mol Genet Genomics ; 295(4): 1063-1078, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32333171

RESUMO

Root-knot nematodes (RKNs, genus Meloidogyne) affect a large number of crops causing severe yield losses worldwide, more specifically in tropical and sub-tropical regions. Several plant species display high resistance levels to Meloidogyne, but a general view of the plant immune molecular responses underlying resistance to RKNs is still lacking. Combining comparative genomics with differential gene expression analysis may allow the identification of widely conserved plant genes involved in RKN resistance. To identify genes that are evolutionary conserved across plant species, we used OrthoFinder to compared the predicted proteome of 22 plant species, including important crops, spanning 214 Myr of plant evolution. Overall, we identified 35,238 protein orthogroups, of which 6,132 were evolutionarily conserved and universal to all the 22 plant species (PLAnts Common Orthogroups-PLACO). To identify host genes responsive to RKN infection, we analyzed the RNA-seq transcriptome data from RKN-resistant genotypes of a peanut wild relative (Arachis stenosperma), coffee (Coffea arabica L.), soybean (Glycine max L.), and African rice (Oryza glaberrima Steud.) challenged by Meloidogyne spp. using EdgeR and DESeq tools, and we found 2,597 (O. glaberrima), 743 (C. arabica), 665 (A. stenosperma), and 653 (G. max) differentially expressed genes (DEGs) during the resistance response to the nematode. DEGs' classification into the previously characterized 35,238 protein orthogroups allowed identifying 17 orthogroups containing at least one DEG of each resistant Arachis, coffee, soybean, and rice genotype analyzed. Orthogroups contain 364 DEGs related to signaling, secondary metabolite production, cell wall-related functions, peptide transport, transcription regulation, and plant defense, thus revealing evolutionarily conserved RKN-responsive genes. Interestingly, the 17 DEGs-containing orthogroups (belonging to the PLACO) were also universal to the 22 plant species studied, suggesting that these core genes may be involved in ancestrally conserved immune responses triggered by RKN infection. The comparative genomic approach that we used here represents a promising predictive tool for the identification of other core plant defense-related genes of broad interest that are involved in different plant-pathogen interactions.


Assuntos
Produtos Agrícolas/genética , Resistência à Doença/genética , Proteínas de Plantas/genética , Tylenchoidea/patogenicidade , Animais , Arachis/genética , Arachis/parasitologia , Café/genética , Café/parasitologia , Produtos Agrícolas/parasitologia , Regulação da Expressão Gênica de Plantas/genética , Genômica , Genótipo , Interações Hospedeiro-Patógeno/genética , Oryza/genética , Oryza/parasitologia , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Imunidade Vegetal/genética , Soja/genética , Soja/parasitologia , Tylenchoidea/genética
12.
BMC Genomics ; 21(1): 280, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245402

RESUMO

BACKGROUND: Phytophthora root rot (PRR) caused by Phytophthora sojae (P. sojae) is one of the most serious limitations to soybean production worldwide. The identification of resistance gene(s) and their incorporation into elite varieties is an effective approach for breeding to prevent soybean from being harmed by this disease. A valuable mapping population of 228 F8:11 recombinant inbred lines (RILs) derived from a cross of the resistant cultivar Guizao1 and the susceptible cultivar BRSMG68 and a high-density genetic linkage map with an average distance of 0.81 centimorgans (cM) between adjacent bin markers in this population were used to map and explore candidate gene(s). RESULTS: PRR resistance in Guizao1 was found to be controlled by a single Mendelian locus and was finely mapped to a 367.371-kb genomic region on chromosome 3 harbouring 19 genes, including 7 disease resistance (R)-like genes, in the reference Willliams 82 genome. Quantitative real-time PCR assays of possible candidate genes revealed that Glyma.03 g05300 was likely involved in PRR resistance. CONCLUSIONS: These findings from the fine mapping of a novel Rps locus will serve as a basis for the cloning and transfer of resistance genes in soybean and the breeding of P. sojae-resistant soybean cultivars through marker-assisted selection.


Assuntos
Resistência à Doença , Phytophthora/patogenicidade , Proteínas de Plantas/genética , Soja/parasitologia , Mapeamento Cromossômico , Cromossomos Bacterianos/genética , Ligação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Melhoramento Vegetal , Doenças das Plantas/parasitologia , Análise de Sequência de DNA , Soja/genética
13.
Plant Mol Biol ; 103(3): 253-267, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32152894

RESUMO

KEY MESSAGE: A novel QTL (qSCN-PL10) for SCN resistance and related candidate genes were identified in the soybean variety Pingliang xiaoheidou, and plant basal immunity seems to contribute to the SCN resistance. Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is one of the most devastating soybean pests worldwide. The development of host plant resistance represents an effective strategy to control SCN. However, owing to the lack of diversity of resistance genes in soybean varieties, further investigation is necessary to identify new SCN resistance genes. By analyzing the resistance phenotypes of soybean variety Pingliang xiaoheidou (Pingliang, ZDD 11047), we found that it exhibited the different resistance phenotypes from PI 88788 and Peking varieties. Because Pingliang variety contains the Rhg1-a (low copy) haplotype and lacks the resistant Rhg4 haplotype, novel quantitative trait locus might account for their SCN resistance. After sequencing parental lines (Magellan and Pingliang) and 200 F2:3 progenies, a high-density genetic map was constructed using the specific length amplified fragment sequencing method and qSCN-PL10 was identified as a novel locus for SCN resistance. Candidate genes were predicted by RNA sequencing (RNA-seq) in the qSCN-PL10 locus region. The RNA-seq analysis performed also indicated that plant basal immunity plays an important role in the resistance of Pingliang to SCN. These results lay a foundation for the use of marker-assisted breeding to enhance the resistance to SCN.


Assuntos
Nematoides/fisiologia , Doenças das Plantas/parasitologia , Soja/fisiologia , Soja/parasitologia , Animais , Mapeamento Cromossômico , Cromossomos de Plantas , Regulação da Expressão Gênica de Plantas , Ligação Genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas , Soja/genética
14.
PLoS One ; 15(3): e0230244, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32160240

RESUMO

Anticarsia gemmatalis (Hübner, 1818) and Chrysodeixis includens (Walker, 1858) are species of Lepidoptera that cause great damages in the soybean plantations of Brazil. Despite the importance they have in this regard, there are no studies on the chromosomal organization of these species and recently, A. gemmatalis, which belonged to the Noctuidae family, was allocated to the Erebidae family. Therefore, the objective of this paper was to analyze, through conventional and molecular cytogenetic markers, both species of Lepidoptera. A 2n = 62 was observed, with ZZ/ZW sex chromosome system and holokinetic chromosomes for both species. There was homogeneity in the number of 18S rDNA sites for both species. However, variations in heterochromatin distribution were observed between both species. The cytogenetic analyses enabled separation of the species, corroborating the transference of A. gemmatalis, from the family Noctuidae to the family Erebidae, suggesting new cytotaxonomic characteristics.


Assuntos
Lepidópteros/genética , Mariposas/genética , Soja/genética , Animais , Proteínas de Bactérias/genética , Brasil , Análise Citogenética , Citogenética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Larva , Lepidópteros/metabolismo , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/genética , Soja/parasitologia
15.
PLoS Pathog ; 16(1): e1008138, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31961913

RESUMO

Eukaryotic heterotrimeric guanine nucleotide-binding proteins consist of α, ß, and γ subunits, which act as molecular switches to regulate a number of fundamental cellular processes. In the oomycete pathogen Phytophthora sojae, the sole G protein α subunit (Gα; encoded by PsGPA1) has been found to be involved in zoospore mobility and virulence, but how it functions remains unclear. In this study, we show that the Gα subunit PsGPA1 directly interacts with PsYPK1, a serine/threonine protein kinase that consists of an N-terminal region with unknown function and a C-terminal region with a conserved catalytic kinase domain. We generated knockout and knockout-complemented strains of PsYPK1 and found that deletion of PsYPK1 resulted in a pronounced reduction in the production of sporangia and oospores, in mycelial growth on nutrient poor medium, and in virulence. PsYPK1 exhibits a cytoplasmic-nuclear localization pattern that is essential for sporangium formation and virulence of P. sojae. Interestingly, PsGPA1 overexpression was found to prevent nuclear localization of PsYPK1 by exclusively binding to the N-terminal region of PsYPK1, therefore accounting for its negative role in sporangium formation. Our data demonstrate that PsGPA1 negatively regulates sporangium formation by repressing the nuclear localization of its downstream kinase PsYPK1.


Assuntos
Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Phytophthora/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Esporos/crescimento & desenvolvimento , Núcleo Celular/genética , Núcleo Celular/metabolismo , Subunidades alfa de Proteínas de Ligação ao GTP/química , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Phytophthora/genética , Phytophthora/crescimento & desenvolvimento , Phytophthora/patogenicidade , Doenças das Plantas/parasitologia , Ligação Proteica , Domínios Proteicos , Transporte Proteico , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Soja/parasitologia , Esporos/enzimologia , Esporos/genética , Esporos/metabolismo , Virulência
16.
Sci Rep ; 10(1): 1390, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996697

RESUMO

The need for larger-scale and increasingly complex protein-protein interaction (PPI) prediction tasks demands that state-of-the-art predictors be highly efficient and adapted to inter- and cross-species predictions. Furthermore, the ability to generate comprehensive interactomes has enabled the appraisal of each PPI in the context of all predictions leading to further improvements in classification performance in the face of extreme class imbalance using the Reciprocal Perspective (RP) framework. We here describe the PIPE4 algorithm. Adaptation of the PIPE3/MP-PIPE sequence preprocessing step led to upwards of 50x speedup and the new Similarity Weighted Score appropriately normalizes for window frequency when applied to any inter- and cross-species prediction schemas. Comprehensive interactomes for three prediction schemas are generated: (1) cross-species predictions, where Arabidopsis thaliana is used as a proxy to predict the comprehensive Glycine max interactome, (2) inter-species predictions between Homo sapiens-HIV1, and (3) a combined schema involving both cross- and inter-species predictions, where both Arabidopsis thaliana and Caenorhabditis elegans are used as proxy species to predict the interactome between Glycine max (the soybean legume) and Heterodera glycines (the soybean cyst nematode). Comparing PIPE4 with the state-of-the-art resulted in improved performance, indicative that it should be the method of choice for complex PPI prediction schemas.


Assuntos
Biologia Computacional/métodos , Interações Hospedeiro-Patógeno , Metabolômica/métodos , Modelos Biológicos , Mapeamento de Interação de Proteínas/métodos , Animais , Arabidopsis/metabolismo , Arabidopsis/parasitologia , Drosophila melanogaster/metabolismo , HIV-1/metabolismo , Humanos , Camundongos , Mapas de Interação de Proteínas/fisiologia , Rabditídios/metabolismo , Saccharomyces cerevisiae/metabolismo , Soja/metabolismo , Soja/parasitologia
17.
Int J Mol Sci ; 21(2)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936278

RESUMO

In plant immune responses, reactive oxygen species (ROS) act as signaling molecules that activate defense pathways against pathogens, especially following resistance (R) gene-mediated pathogen recognition. Glutathione (GSH), an antioxidant and redox regulator, participates in the removal of hydrogen peroxide (H2O2). However, the mechanism of GSH-mediated H2O2 generation in soybeans (Glycine max (L.) Merr.) that are resistant to the soybean cyst nematode (SCN; Heterodera glycines Ichinohe) remains unclear. To elucidate this underlying relationship, the feeding of race 3 of H. glycines with resistant cultivars, Peking and PI88788, was compared with that on a susceptible soybean cultivar, Williams 82. After 5, 10, and 15 days of SCN infection, we quantified γ-glutamylcysteine (γ-EC) and (homo)glutathione ((h)GSH), and a gene expression analysis showed that GSH metabolism in resistant cultivars differed from that in susceptible soybean roots. ROS accumulation was examined both in resistant and susceptible roots upon SCN infection. The time of intense ROS generation was related to the differences of resistance mechanisms in Peking and PI88788. ROS accumulation that was caused by the (h)GSH depletion-arrested nematode development in susceptible Williams 82. These results suggest that (h)GSH metabolism in resistant soybeans plays a key role in the regulation of ROS-generated signals, leading to resistance against nematodes.


Assuntos
Resistência à Doença/genética , Glutationa/genética , Infecções por Nematoides/genética , Soja/genética , Animais , Genótipo , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Infecções por Nematoides/metabolismo , Infecções por Nematoides/parasitologia , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Espécies Reativas de Oxigênio/metabolismo , Soja/crescimento & desenvolvimento , Soja/parasitologia
18.
Theor Appl Genet ; 133(1): 87-102, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31570969

RESUMO

KEY MESSAGE: Root transcriptome profiling of three soybean cultivars and a wild relative infected with soybean cyst nematode at migratory phase revealed differential resistance pathway responses between resistant and susceptible genotypes. The soybean cyst nematode (SCN), Heterodera glycines, is the most serious pathogen of soybean production throughout the world. Using resistant cultivars is the primary management strategy against SCN infestation. To gain insight into the still obscure mechanisms of genetic resistance to nematodes in different soybean genotypes, RNA-Seq profiling of the roots of Glycine max cv. Peking, Fayette, Williams 82, and a wild relative (Glycine soja PI 468916) was performed during SCN infection at the migratory phase. The analysis showed statistically significant changes of expression beginning at eight hours after inoculation in genes associated with defense mechanisms and pathways, such as the phenylpropanoid biosynthesis pathway, plant innate immunity and hormone signaling. Our results indicate the importance of the early plant response to migratory phase nematodes in pathogenicity determination. The transcriptome changes occurring during early SCN infection included a number of genes and pathways specific to the different resistant genotypes. We observed the most extensive resistant transcriptome reaction in PI 468916, where the resistant response was qualitatively different from that of commonly used G. max varieties.


Assuntos
Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Soja/genética , Soja/parasitologia , Transcrição Genética , Tylenchoidea/fisiologia , Animais , Vias Biossintéticas/genética , Mapeamento Cromossômico , Suscetibilidade a Doenças , Etilenos/biossíntese , Perfilação da Expressão Gênica , Ontologia Genética , Genes de Plantas , Filogenia , Doenças das Plantas/parasitologia , Propanóis/metabolismo , Análise de Sequência de RNA , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo
19.
Sci Rep ; 9(1): 18201, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796830

RESUMO

Anticarsia gemmatalis (velvetbean caterpillar) and Chrysodeixis includens (soybean looper) are two important defoliation pests of soybeans. In the present study, we have investigated the susceptibility and brush border membrane-binding properties of both species to Bacillus thuringiensis Cry1Ea toxin. Bioassays performed in first-instar larvae demonstrated potent activity against both soybean pests in terms of mortality or practical mortality. Competition-binding studies carried out with 125Iodine-labelled Cry1Ea, demonstrated the presence of specific binding sites on the midgut brush border membrane vesicles (BBMV) of both insect species. Heterologous competition-binding experiments indicated that Cry1Ea does not share binding sites with Cry1Ac or Cry1Fa in either soybean pest. This study contributes to the knowledge of Cry1Ea toxicity and midgut binding sites in A. gemmatalis and C. includens and sheds light on the cross-resistance potential of Cry1Ea with other Bt proteins aimed at controlling lepidopteran pests in soybeans.


Assuntos
Proteínas de Bactérias/farmacologia , Agentes de Controle Biológico/farmacologia , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Soja/parasitologia , Animais , Sítios de Ligação , Bioensaio , Larva/metabolismo , Microvilosidades/metabolismo , Mariposas/citologia , Mariposas/metabolismo
20.
BMC Genomics ; 20(1): 904, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775625

RESUMO

BACKGROUND: Soybean cyst nematode (SCN), Heterodera glycines Ichinohe, has been one of the most devastating pathogens affecting soybean production. In the United States alone, SCN damage accounted for more than $1 billion loss annually. With a narrow genetic background of the currently available SCN-resistant commercial cultivars, high risk of resistance breakdown can occur. The objectives of this study were to conduct a genome-wide association study (GWAS) to identify QTL, SNP markers, and candidate genes associated with soybean leaf chlorophyll content tolerance to SCN infection, and to carry out a genomic selection (GS) study for the chlorophyll content tolerance. RESULTS: A total of 172 soybean genotypes were evaluated for the effect of SCN HG Type 1.2.3.5.6.7 (race 4) on soybean leaf chlorophyll. The soybean lines were genotyped using a total of 4089 filtered and high-quality SNPs. Results showed that (1) a large variation in SCN tolerance based on leaf chlorophyll content indices (CCI); (2) a total of 22, 14, and 16 SNPs associated with CCI of non-SCN-infected plants, SCN-infected plants, and reduction of CCI SCN, respectively; (3) a new locus of chlorophyll content tolerance to SCN mapped on chromosome 3; (4) candidate genes encoding for Leucine-rich repeat protein, plant hormone signaling molecules, and biomolecule transporters; and (5) an average GS accuracy ranging from 0.31 to 0.46 with all SNPs and varying from 0.55 to 0.76 when GWAS-derived SNP markers were used across five models. This study demonstrated the potential of using genome-wide selection to breed chlorophyll-content-tolerant soybean for managing SCN. CONCLUSIONS: In this study, soybean accessions with higher CCI under SCN infestation, and molecular markers associated with chlorophyll content related to SCN were identified. In addition, a total of 15 candidate genes associated with chlorophyll content tolerance to SCN in soybean were also identified. These candidate genes will lead to a better understanding of the molecular mechanisms that control chlorophyll content tolerance to SCN in soybean. Genomic selection analysis of chlorophyll content tolerance to SCN showed that using significant SNPs obtained from GWAS could provide better GS accuracy.


Assuntos
Clorofila/metabolismo , Genoma de Planta , Estudo de Associação Genômica Ampla , Genômica , Interações Hospedeiro-Parasita/genética , Soja/genética , Soja/metabolismo , Animais , Genes de Plantas , Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Fenótipo , Polimorfismo de Nucleotídeo Único , Seleção Genética , Soja/parasitologia , Tylenchoidea
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