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1.
Int J Mol Sci ; 25(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39000408

RESUMO

Nucleotide-binding and leucine-rich repeat receptors (NLRs) are the most important and largest class of immune receptors in plants. The Pi36 gene encodes a canonical CC-NBS-LRR protein that confers resistance to rice blast fungal infections. Here, we show that the CC domain of Pi36 plays a role in cell death induction. Furthermore, self-association is required for the CC domain-mediated cell death, and the self-association ability is correlated with the cell death level. In addition, the NB-ARC domain may suppress the activity of the CC domain through intramolecular interaction. The mutations D440G next to the RNBS-D motif and D503V in the MHD motif autoactivated Pi36, but the mutation K212 in the P-loop motif inhibited this autoactivation, indicating that nucleotide binding of the NB-ARC domain is essential for Pi36 activation. We also found that the LRR domain is required for D503V- and D440G-mediated Pi36 autoactivation. Interestingly, several mutations in the CC domain compromised the CC domain-mediated cell death without affecting the D440G- or D503V-mediated Pi36 autoactivation. The autoactivate Pi36 variants exhibited stronger self-associations than the inactive variants. Taken together, we speculated that the CC domain of Pi36 executes cell death activities, whereas the NB-ARC domain suppressed CC-mediated cell death via intermolecular interaction. The NB-ARC domain releases its suppression of the CC domain and strengthens the self-association of Pi36 to support the CC domain, possibly through nucleotide exchange.


Assuntos
Proteínas NLR , Oryza , Proteínas de Plantas , Oryza/metabolismo , Oryza/genética , Oryza/imunologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/química , Proteínas NLR/metabolismo , Proteínas NLR/genética , Proteínas NLR/química , Morte Celular , Mutação , Receptores Imunológicos/metabolismo , Receptores Imunológicos/genética , Doenças das Plantas/imunologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Domínios Proteicos , Resistência à Doença/genética , Imunidade Vegetal/genética
2.
Cell Host Microbe ; 32(7): 1114-1128.e10, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38955187

RESUMO

Plant immune homeostasis is achieved through a balanced immune activation and suppression, enabling effective defense while averting autoimmunity. In Arabidopsis, disrupting a mitogen-activated protein (MAP) kinase cascade triggers nucleotide-binding leucine-rich-repeat (NLR) SUPPRESSOR OF mkk1/2 2 (SUMM2)-mediated autoimmunity. Through an RNAi screen, we identify PUB5, a putative plant U-box E3 ligase, as a critical regulator of SUMM2-mediated autoimmunity. In contrast to typical E3 ligases, PUB5 stabilizes CRCK3, a calmodulin-binding receptor-like cytoplasmic kinase involved in SUMM2 activation. A closely related E3 ligase, PUB44, functions oppositely with PUB5 to degrade CRCK3 through monoubiquitylation and internalization. Furthermore, CRCK3, highly expressed in roots and conserved across plant species, confers resistance to Fusarium oxysporum, a devastating soil-borne fungal pathogen, in both Arabidopsis and cotton. These findings demonstrate the antagonistic role of an E3 ligase pair in fine-tuning kinase proteostasis for the regulation of NLR-mediated autoimmunity and highlight the function of autoimmune activators in governing plant root immunity against fungal pathogens.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Autoimunidade , Resistência à Doença , Fusarium , Doenças das Plantas , Imunidade Vegetal , Ubiquitina-Proteína Ligases , Arabidopsis/imunologia , Arabidopsis/microbiologia , Arabidopsis/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Fusarium/imunologia , Proteínas NLR/metabolismo , Proteínas NLR/genética , Regulação da Expressão Gênica de Plantas , Ubiquitinação , Proteínas de Transporte
3.
Int J Mol Sci ; 25(12)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38928313

RESUMO

Wheat powdery mildew is an important fungal disease that seriously jeopardizes wheat production, which poses a serious threat to food safety. SJ106 is a high-quality, disease-resistant spring wheat variety; this disease resistance is derived from Wheat-wheatgrass 33. In this study, the powdery mildew resistance genes in SJ106 were located at the end of chromosome 6DS, a new disease resistance locus tentatively named PmSJ106 locus. This interval was composed of a nucleotide-binding leucine-rich repeat (NLR) gene cluster containing 19 NLR genes. Five NLRs were tandem duplicated genes, and one of them (a coiled coil domain-nucleotide binding site-leucine-rich repeat (CC-NBS-LRR; CNL) type gene, TaRGA5-like) expressed 69-836-fold in SJ106 compared with the susceptible control. The genome DNA and cDNA sequences of TaRGA5-like were amplified from SJ106, which contain several nucleotide polymorphisms in LRR regions compared with susceptible individuals and Chinese Spring. Overexpression of TaRGA5-like significantly increased resistance to powdery mildew in susceptible receptor wheat Jinqiang5. However, Virus induced gene silence (VIGS) of TaRGA5-like resulted in only a small decrease of SJ106 in disease resistance, presumably compensated by other NLR duplicated genes. The results suggested that TaRGA5-like confers partial powdery mildew resistance in SJ106. As a member of the PmSJ106 locus, TaRGA5-like functioned together with other NLR duplicated genes to improve wheat resistance to powdery mildew. Wheat variety SJ106 would become a novel and potentially valuable germplasm for powdery mildew resistance.


Assuntos
Ascomicetos , Resistência à Doença , Proteínas NLR , Doenças das Plantas , Proteínas de Plantas , Triticum , Triticum/genética , Triticum/microbiologia , Resistência à Doença/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas NLR/genética , Ascomicetos/patogenicidade , Mapeamento Cromossômico , Genes de Plantas , Família Multigênica , Regulação da Expressão Gênica de Plantas , Cromossomos de Plantas/genética
4.
Plant Mol Biol ; 114(4): 78, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922375

RESUMO

Both prokaryotic and eukaryotic organisms use the nucleotide-binding domain/leucine-rich repeat (NBD/LRR)-triggered immunity (NLR-triggered immunity) signaling pathway to defend against pathogens. Plant NLRs are intracellular immune receptors that can bind to effector proteins secreted by pathogens. Dicotyledonous plants express a type of NLR known as TIR domain-containing NLRs (TNLs). TIR domains are enzymes that catalyze the production of small molecules that are essential for immune signaling and lead to plant cell death. The activation of downstream TNL signaling components, such as enhanced disease susceptibility 1 (EDS1), phytoalexin deficient 4 (PAD4), and senescence-associated gene 101 (SAG101), is facilitated by these small molecules. Helper NLRs (hNLRs) and the EDS1-PAD4/SAG101 complex associate after activation, causing the hNLRs to oligomerize, translocate to the plasma membrane (PM), and produce cation-selective channels. According to a recent theory, cations enter cells through pores created by oligomeric hNLRs and trigger cell death. Occasionally, TNLs can self-associate to create higher-order oligomers. Here, we categorized soybean TNLs based on the protein domains that they possess. We believe that TNLs may help soybean plants effectively fight pathogens by acting as a source of genetic resistance. In summary, the purpose of this review is to elucidate the range of TNLs that are expressed in soybean.


Assuntos
Glycine max , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Glycine max/genética , Glycine max/metabolismo , Glycine max/imunologia , Proteínas NLR/metabolismo , Proteínas NLR/genética , Domínios Proteicos , Imunidade Vegetal/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Transdução de Sinais , Regulação da Expressão Gênica de Plantas
5.
Front Immunol ; 15: 1393851, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919626

RESUMO

Tendinitis, characterized by the inflammation of tendons, poses significant challenges in both diagnosis and treatment due to its multifaceted etiology and complex pathophysiology. This study aimed to dissect the molecular mechanisms underlying tendinitis, with a particular focus on inflammasome-related genes and their interactions with the immune system. Through comprehensive gene expression analysis and bioinformatics approaches, we identified distinct expression profiles of inflammasome genes, such as NLRP6, NLRP1, and MEFV, which showed significant correlations with immune checkpoint molecules, indicating a pivotal role in the inflammatory cascade of tendinitis. Additionally, MYD88 and CD36 were found to be closely associated with HLA family molecules, underscoring their involvement in immune response modulation. Contrary to expectations, chemokines exhibited minimal correlation with inflammasome genes, suggesting an unconventional inflammatory pathway in tendinitis. Transcription factors like SP110 and CREB5 emerged as key regulators of inflammasome genes, providing insight into the transcriptional control mechanisms in tendinitis. Furthermore, potential therapeutic targets were identified through the DGidb database, highlighting drugs that could modulate the activity of inflammasome genes, offering new avenues for targeted tendinitis therapy. Our findings elucidate the complex molecular landscape of tendinitis, emphasizing the significant role of inflammasomes and immune interactions, and pave the way for the development of novel diagnostic and therapeutic strategies.


Assuntos
Inflamassomos , Tendinopatia , Inflamassomos/genética , Inflamassomos/metabolismo , Inflamassomos/imunologia , Humanos , Tendinopatia/genética , Tendinopatia/imunologia , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Pirina/genética , Proteínas NLR/genética , Regulação da Expressão Gênica , Transcriptoma , Redes Reguladoras de Genes
6.
Genome Biol Evol ; 16(6)2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38787537

RESUMO

Nucleotide-binding domain and leucine-rich repeat (NLR) immune receptor genes form a major line of defense in plants, acting in both pathogen recognition and resistance machinery activation. NLRs are reported to form large gene clusters in limber pine (Pinus flexilis), but it is unknown how widespread this genomic architecture may be among the extant species of conifers (Pinophyta). We used comparative genomic analyses to assess patterns in the abundance, diversity, and genomic distribution of NLR genes. Chromosome-level whole genome assemblies and high-density linkage maps in the Pinaceae, Cupressaceae, Taxaceae, and other gymnosperms were scanned for NLR genes using existing and customized pipelines. The discovered genes were mapped across chromosomes and linkage groups and analyzed phylogenetically for evolutionary history. Conifer genomes are characterized by dense clusters of NLR genes, highly localized on one chromosome. These clusters are rich in TNL-encoding genes, which seem to have formed through multiple tandem duplication events. In contrast to angiosperms and nonconiferous gymnosperms, genomic clustering of NLR genes is ubiquitous in conifers. NLR-dense genomic regions are likely to influence a large part of the plant's resistance, informing our understanding of adaptation to biotic stress and the development of genetic resources through breeding.


Assuntos
Cromossomos de Plantas , Proteínas NLR , Traqueófitas , Proteínas NLR/genética , Cromossomos de Plantas/genética , Traqueófitas/genética , Filogenia , Genoma de Planta , Evolução Molecular , Proteínas de Plantas/genética , Família Multigênica
7.
Sci Rep ; 14(1): 12253, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806545

RESUMO

Overexpression of Glycine max disease resistant 1 (GmDR1) exhibits broad-spectrum resistance against Fusarium virguliforme, Heterodera glycines (soybean cyst nematode), Tetranychus urticae (Koch) (spider mites), and Aphis glycines Matsumura (soybean aphids) in soybean. To understand the mechanisms of broad-spectrum immunity mediated by GmDR1, the transcriptomes of a strong and a weak GmDR1-overexpressor following treatment with chitin, a pathogen- and pest-associated molecular pattern (PAMP) common to these organisms, were investigated. The strong and weak GmDR1-overexpressors exhibited altered expression of 6098 and 992 genes, respectively, as compared to the nontransgenic control following chitin treatment. However, only 192 chitin- and 115 buffer-responsive genes exhibited over two-fold changes in expression levels in both strong and weak GmDR1-overexpressors as compared to the control. MapMan analysis of the 192 chitin-responsive genes revealed 64 biotic stress-related genes, of which 53 were induced and 11 repressed as compared to the control. The 53 chitin-induced genes include nine genes that encode receptor kinases, 13 encode nucleotide-binding leucine-rich repeat (NLR) receptor proteins, seven encode WRKY transcription factors, four ethylene response factors, and three MYB-like transcription factors. Investigation of a subset of these genes revealed three receptor protein kinases, seven NLR proteins, and one WRKY transcription factor genes that are induced following F. virguliforme and H. glycines infection. The integral plasma membrane GmDR1 protein most likely recognizes PAMPs including chitin and activates transcription of genes encoding receptor kinases, NLR proteins and defense-related genes. GmDR1 could be a pattern recognition receptor that regulates the expression of several NLRs for expression of PAMP-triggered immunity and/or priming the effector triggered immunity.


Assuntos
Resistência à Doença , Regulação da Expressão Gênica de Plantas , Glycine max , Proteínas NLR , Doenças das Plantas , Proteínas de Plantas , Glycine max/parasitologia , Glycine max/genética , Resistência à Doença/genética , Doenças das Plantas/parasitologia , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas NLR/metabolismo , Proteínas NLR/genética , Animais , Fusarium , Quitina/metabolismo , Membrana Celular/metabolismo , Transcriptoma , Plantas Geneticamente Modificadas
8.
New Phytol ; 243(1): 330-344, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38742296

RESUMO

Arabidopsis Col-0 RPP2A and RPP2B confer recognition of Arabidopsis downy mildew (Hyaloperonospora arabidopsidis [Hpa]) isolate Cala2, but the identity of the recognized ATR2Cala2 effector was unknown. To reveal ATR2Cala2, an F2 population was generated from a cross between Hpa-Cala2 and Hpa-Noks1. We identified ATR2Cala2 as a non-canonical RxLR-type effector that carries a signal peptide, a dEER motif, and WY domains but no RxLR motif. Recognition of ATR2Cala2 and its effector function were verified by biolistic bombardment, ectopic expression and Hpa infection. ATR2Cala2 is recognized in accession Col-0 but not in Ler-0 in which RPP2A and RPP2B are absent. In ATR2Emoy2 and ATR2Noks1 alleles, a frameshift results in an early stop codon. RPP2A and RPP2B are essential for the recognition of ATR2Cala2. Stable and transient expression of ATR2Cala2 under 35S promoter in Arabidopsis and Nicotiana benthamiana enhances disease susceptibility. Two additional Col-0 TIR-NLR (TNL) genes (RPP2C and RPP2D) adjacent to RPP2A and RPP2B are quantitatively required for full resistance to Hpa-Cala2. We compared RPP2 haplotypes in multiple Arabidopsis accessions and showed that all four genes are present in all ATR2Cala2-recognizing accessions.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Oomicetos , Doenças das Plantas , Arabidopsis/genética , Arabidopsis/microbiologia , Arabidopsis/imunologia , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Oomicetos/patogenicidade , Proteínas NLR/metabolismo , Proteínas NLR/genética , Nicotiana/genética , Nicotiana/microbiologia , Nicotiana/imunologia , Sequência de Aminoácidos , Alelos
9.
New Phytol ; 243(1): 345-361, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757730

RESUMO

Nucleotide-binding domain and leucine-rich repeat (NLR) proteins with pathogen sensor activities have evolved to initiate immune signaling by activating helper NLRs. However, the mechanisms underpinning helper NLR activation by sensor NLRs remain poorly understood. Although coiled coil (CC) type sensor NLRs such as the Potato virus X disease resistance protein Rx have been shown to activate the oligomerization of their downstream helpers NRC2, NRC3 and NRC4, the domains involved in sensor-helper signaling are not known. Here, we used Agrobacterium tumefaciens-mediated transient expression in Nicotiana benthamiana to show that the nucleotide-binding (NB) domain within the NB-ARC of Rx is necessary and sufficient for oligomerization and immune signaling of downstream helper NLRs. In addition, the NB domains of the disease resistance proteins Gpa2 (cyst nematode resistance), Rpi-amr1, Rpi-amr3 (oomycete resistance) and Sw-5b (virus resistance) are also sufficient to activate their respective downstream NRC helpers. Using transient expression in the lettuce (Lactuca sativa), we show that Rx (both as full length or as NB domain truncation) and its helper NRC2 form a minimal functional unit that can be transferred from solanaceous plants (lamiids) to Campanulid species. Our results challenge the prevailing paradigm that NLR proteins exclusively signal via their N-terminal domains and reveal a signaling activity for the NB domain of NRC-dependent sensor NLRs. We propose a model in which helper NLRs can perceive the status of the NB domain of their upstream sensors.


Assuntos
Resistência à Doença , Proteínas NLR , Nicotiana , Proteínas de Plantas , Domínios Proteicos , Transdução de Sinais , Nicotiana/genética , Nicotiana/imunologia , Proteínas NLR/metabolismo , Proteínas NLR/genética , Resistência à Doença/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Lactuca/genética , Lactuca/imunologia , Multimerização Proteica , Nucleotídeos/metabolismo , Doenças das Plantas/virologia , Doenças das Plantas/imunologia , Plantas Geneticamente Modificadas , Imunidade Vegetal
10.
Nat Commun ; 15(1): 4610, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816417

RESUMO

NLR family proteins act as intracellular receptors. Gene duplication amplifies the number of NLR genes, and subsequent mutations occasionally provide modifications to the second gene that benefits immunity. However, evolutionary processes after gene duplication and functional relationships between duplicated NLRs remain largely unclear. Here, we report that the rice NLR protein Pit1 is associated with its paralogue Pit2. The two are required for the resistance to rice blast fungus but have different functions: Pit1 induces cell death, while Pit2 competitively suppresses Pit1-mediated cell death. During evolution, the suppression of Pit1 by Pit2 was probably generated through positive selection on two fate-determining residues in the NB-ARC domain of Pit2, which account for functional differences between Pit1 and Pit2. Consequently, Pit2 lost its plasma membrane localization but acquired a new function to interfere with Pit1 in the cytosol. These findings illuminate the evolutionary trajectory of tandemly duplicated NLR genes after gene duplication.


Assuntos
Duplicação Gênica , Proteínas NLR , Oryza , Proteínas de Plantas , Proteínas NLR/genética , Proteínas NLR/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Evolução Molecular , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Resistência à Doença/genética , Morte Celular , Filogenia , Regulação da Expressão Gênica de Plantas
11.
Int J Mol Sci ; 25(10)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38791594

RESUMO

In plants, nucleotide-binding site and leucine-rich repeat proteins (NLRs) play pivotal roles in effector-triggered immunity (ETI). However, the precise mechanisms underlying NLR-mediated disease resistance remain elusive. Previous studies have demonstrated that the NLR gene pair Pik-H4 confers resistance to rice blast disease by interacting with the transcription factor OsBIHD1, consequently leading to the upregulation of hormone pathways. In the present study, we identified an RNA recognition motif (RRM) protein, OsRRM2, which interacted with Pik1-H4 and Pik2-H4 in vesicles and chloroplasts. OsRRM2 exhibited a modest influence on Pik-H4-mediated rice blast resistance by upregulating resistance genes and genes associated with chloroplast immunity. Moreover, the RNA-binding sequence of OsRRM2 was elucidated using systematic evolution of ligands by exponential enrichment. Transcriptome analysis further indicated that OsRRM2 promoted RNA editing of the chloroplastic gene ndhB. Collectively, our findings uncovered a chloroplastic RRM protein that facilitated the translocation of the NLR gene pair and modulated chloroplast immunity, thereby bridging the gap between ETI and chloroplast immunity.


Assuntos
Cloroplastos , Regulação da Expressão Gênica de Plantas , Oryza , Imunidade Vegetal , Proteínas de Plantas , Cloroplastos/metabolismo , Cloroplastos/genética , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Oryza/genética , Oryza/metabolismo , Oryza/imunologia , Proteínas de Repetições Ricas em Leucina , Sítios de Ligação , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/genética , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Resistência à Doença/genética , Proteínas NLR/metabolismo , Proteínas NLR/genética , Edição de RNA
12.
Arch Microbiol ; 206(5): 241, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698267

RESUMO

The epidemic of stripe rust, caused by the pathogen Puccinia striiformis f. sp. tritici (Pst), would reduce wheat (Triticum aestivum) yields seriously. Traditional experimental methods are difficult to discover the interaction between wheat and Pst. Multi-omics data analysis provides a new idea for efficiently mining the interactions between host and pathogen. We used 140 wheat-Pst RNA-Seq data to screen for differentially expressed genes (DEGs) between low susceptibility and high susceptibility samples, and carried out Gene Ontology (GO) enrichment analysis. Based on this, we constructed a gene co-expression network, identified the core genes and interacted gene pairs from the conservative modules. Finally, we checked the distribution of Nucleotide-binding and leucine-rich repeat (NLR) genes in the co-expression network and drew the wheat NLR gene co-expression network. In order to provide accessible information for related researchers, we built a web-based visualization platform to display the data. Based on the analysis, we found that resistance-related genes such as TaPR1, TaWRKY18 and HSP70 were highly expressed in the network. They were likely to be involved in the biological processes of Pst infecting wheat. This study can assist scholars in conducting studies on the pathogenesis and help to advance the investigation of wheat-Pst interaction patterns.


Assuntos
Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno , Doenças das Plantas , Puccinia , Triticum , Triticum/microbiologia , Doenças das Plantas/microbiologia , Puccinia/genética , Resistência à Doença/genética , Ontologia Genética , Regulação da Expressão Gênica de Plantas , Proteínas NLR/genética , Proteínas NLR/metabolismo , Basidiomycota/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica
13.
Clin Epigenetics ; 16(1): 58, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38658973

RESUMO

Alzheimer's disease (AD) prevalence is twice as high in non-Hispanic Blacks (NHBs) as in non-Hispanic Whites (NHWs). The objective of this study was to determine whether aberrant methylation at imprint control regions (ICRs) is associated with AD. Differentially methylated regions (DMRs) were bioinformatically identified from whole-genome bisulfite sequenced DNA derived from brain tissue of 9 AD (5 NHBs and 4 NHWs) and 8 controls (4 NHBs and 4 NHWs). We identified DMRs located within 120 regions defined as candidate ICRs in the human imprintome ( https://genome.ucsc.edu/s/imprintome/hg38.AD.Brain_track ). Eighty-one ICRs were differentially methylated in NHB-AD, and 27 ICRs were differentially methylated in NHW-AD, with two regions common to both populations that are proximal to the inflammasome gene, NLRP1, and a known imprinted gene, MEST/MESTIT1. These findings indicate that early developmental alterations in DNA methylation of regions regulating genomic imprinting may contribute to AD risk and that this epigenetic risk differs between NHBs and NHWs.


Assuntos
Doença de Alzheimer , Metilação de DNA , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Doença de Alzheimer/genética , Doença de Alzheimer/etnologia , Negro ou Afro-Americano/genética , Estudos de Casos e Controles , Metilação de DNA/genética , Epigênese Genética/genética , Impressão Genômica/genética , Proteínas NLR/genética , Brancos/genética
14.
Plant Cell ; 36(7): 2491-2511, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38598645

RESUMO

Nucleotide-binding domain and leucine-rich repeat (NLR) proteins are a prominent class of intracellular immune receptors in plants. However, our understanding of plant NLR structure and function is limited to the evolutionarily young flowering plant clade. Here, we describe an extended spectrum of NLR diversity across divergent plant lineages and demonstrate the structural and functional similarities of N-terminal domains that trigger immune responses. We show that the broadly distributed coiled-coil (CC) and toll/interleukin-1 receptor (TIR) domain families of nonflowering plants retain immune-related functions through translineage activation of cell death in the angiosperm Nicotiana benthamiana. We further examined a CC subfamily specific to nonflowering lineages and uncovered an essential N-terminal MAEPL motif that is functionally comparable with motifs in resistosome-forming CC-NLRs. Consistent with a conserved role in immunity, the ectopic activation of CCMAEPL in the nonflowering liverwort Marchantia polymorpha led to profound growth inhibition, defense gene activation, and signatures of cell death. Moreover, comparative transcriptomic analyses of CCMAEPL activity delineated a common CC-mediated immune program shared across evolutionarily divergent nonflowering and flowering plants. Collectively, our findings highlight the ancestral nature of NLR-mediated immunity during plant evolution that dates its origin to at least ∼500 million years ago.


Assuntos
Marchantia , Proteínas NLR , Nicotiana , Proteínas de Plantas , Proteínas NLR/genética , Proteínas NLR/metabolismo , Nicotiana/genética , Nicotiana/imunologia , Nicotiana/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Marchantia/genética , Marchantia/imunologia , Marchantia/metabolismo , Domínios Proteicos , Filogenia , Imunidade Vegetal/genética , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Regulação da Expressão Gênica de Plantas
16.
Plant J ; 118(6): 2249-2268, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38430487

RESUMO

Melon (Cucumis melo L.), being under intensive domestication and selective breeding, displays an abundant phenotypic diversity. Wild germplasm with tolerance to stress represents an untapped genetic resource for discovery of disease-resistance genes. To comprehensively characterize resistance genes in melon, we generate a telomere-to-telomere (T2T) and gap-free genome of wild melon accession PI511890 (C. melo var. chito) with a total length of 375.0 Mb and a contig N50 of 31.24 Mb. The complete genome allows us to dissect genome architecture and identify resistance gene analogs. We construct a pan-NLRome using seven melon genomes, which include 208 variable and 18 core nucleotide-binding leucine-rich repeat receptors (NLRs). Multiple disease-related transcriptome analyses indicate that most up-regulated NLRs induced by pathogens are shell or cloud NLRs. The T2T gap-free assembly and the pan-NLRome not only serve as essential resources for genomic studies and molecular breeding of melon but also provide insights into the genome architecture and NLR diversity.


Assuntos
Cucumis melo , Resistência à Doença , Genoma de Planta , Genoma de Planta/genética , Cucumis melo/genética , Resistência à Doença/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Doenças das Plantas/genética , Proteínas NLR/genética , Proteínas NLR/metabolismo , Cucurbitaceae/genética
17.
Nature ; 627(8005): 847-853, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38480885

RESUMO

Plant nucleotide-binding leucine-rich repeat (NLR) immune receptors with an N-terminal Toll/interleukin-1 receptor (TIR) domain mediate recognition of strain-specific pathogen effectors, typically via their C-terminal ligand-sensing domains1. Effector binding enables TIR-encoded enzymatic activities that are required for TIR-NLR (TNL)-mediated immunity2,3. Many truncated TNL proteins lack effector-sensing domains but retain similar enzymatic and immune activities4,5. The mechanism underlying the activation of these TIR domain proteins remain unclear. Here we show that binding of the TIR substrates NAD+ and ATP induces phase separation of TIR domain proteins in vitro. A similar condensation occurs with a TIR domain protein expressed via its native promoter in response to pathogen inoculation in planta. The formation of TIR condensates is mediated by conserved self-association interfaces and a predicted intrinsically disordered loop region of TIRs. Mutations that disrupt TIR condensates impair the cell death activity of TIR domain proteins. Our data reveal phase separation as a mechanism for the activation of TIR domain proteins and provide insight into substrate-induced autonomous activation of TIR signalling to confer plant immunity.


Assuntos
Trifosfato de Adenosina , Arabidopsis , NAD , Nicotiana , Separação de Fases , Proteínas de Plantas , Domínios Proteicos , Trifosfato de Adenosina/metabolismo , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/imunologia , Proteínas de Arabidopsis/metabolismo , Morte Celular , Mutação , NAD/metabolismo , Nicotiana/genética , Nicotiana/imunologia , Nicotiana/metabolismo , Proteínas NLR/química , Proteínas NLR/genética , Proteínas NLR/imunologia , Proteínas NLR/metabolismo , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Domínios Proteicos/genética , Receptores Imunológicos/química , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Transdução de Sinais , Receptores Toll-Like/química , Receptores de Interleucina-1/química
18.
EMBO Rep ; 25(5): 2306-2322, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38528170

RESUMO

Plants rely on Nucleotide-binding, Leucine-rich repeat Receptors (NLRs) for pathogen recognition. Highly variable NLRs (hvNLRs) show remarkable intraspecies diversity, while their low-variability paralogs (non-hvNLRs) are conserved between ecotypes. At a population level, hvNLRs provide new pathogen-recognition specificities, but the association between allelic diversity and genomic and epigenomic features has not been established. Our investigation of NLRs in Arabidopsis Col-0 has revealed that hvNLRs show higher expression, less gene body cytosine methylation, and closer proximity to transposable elements than non-hvNLRs. hvNLRs show elevated synonymous and nonsynonymous nucleotide diversity and are in chromatin states associated with an increased probability of mutation. Diversifying selection maintains variability at a subset of codons of hvNLRs, while purifying selection maintains conservation at non-hvNLRs. How these features are established and maintained, and whether they contribute to the observed diversity of hvNLRs is key to understanding the evolution of plant innate immune receptors.


Assuntos
Alelos , Proteínas de Arabidopsis , Arabidopsis , Variação Genética , Proteínas NLR , Arabidopsis/genética , Proteínas NLR/genética , Proteínas NLR/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Genoma de Planta , Regulação da Expressão Gênica de Plantas , Metilação de DNA/genética , Genômica/métodos , Evolução Molecular
19.
Biomolecules ; 14(3)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38540722

RESUMO

Schizophrenia is a complex mental condition, with key symptoms marked for diagnosis including delusions, hallucinations, disorganized thinking, reduced emotional expression, and social dysfunction. In the context of major developmental hypotheses of schizophrenia, notably those concerning maternal immune activation and neuroinflammation, we studied NLRP1 expression and content in the postmortem brain tissue of 10 schizophrenia and 10 control subjects. In the medial orbitofrontal cortex (Brodmann's area 11/12) and dorsolateral prefrontal cortex (area 46) from both hemispheres of six schizophrenia subjects, the NLRP1 mRNA expression was significantly higher than in six control brains (p < 0.05). As the expression difference was highest for the medial orbitofrontal cortex in the right hemisphere, we assessed NLRP1-immunoreactive pyramidal neurons in layers III, V, and VI in the medial orbitofrontal cortex in the right hemisphere of seven schizophrenia and five control brains. Compared to controls, we quantified a significantly higher number of NLRP1-positive pyramidal neurons in the schizophrenia brains (p < 0.01), suggesting NLRP1 inflammasome activation in schizophrenia subjects. Layer III pyramidal neuron dysfunction aligns with working memory deficits, while impairments of pyramidal neurons in layers V and VI likely disrupt predictive processing. We propose NLRP1 inflammasome as a potential biomarker and therapeutic target in schizophrenia.


Assuntos
Esquizofrenia , Humanos , Inflamassomos/genética , Inflamassomos/metabolismo , Córtex Cerebral/metabolismo , Córtex Pré-Frontal/metabolismo , Células Piramidais/metabolismo , Proteínas NLR/genética , Proteínas NLR/metabolismo
20.
Plant Physiol ; 195(1): 832-849, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38306630

RESUMO

Plant innate immunity mediated by the nucleotide-binding leucine-rich repeat (NLR) class of immune receptors plays an important role in defense against various pathogens. Although key biochemical events involving NLR activation and signaling have been recently uncovered, we know very little about the transcriptional regulation of NLRs and their downstream signaling components. Here, we show that the Toll-Interleukin 1 receptor homology domain containing NLR (TNL) gene N (Necrosis), which confers resistance to Tobacco mosaic virus, is transcriptionally induced upon immune activation. We identified two conserved transcription factors, N required C3H zinc finger 1 (NRZ1) and N required MYB-like transcription factor 1 (NRM1), that activate N in an immune responsive manner. Genetic analyses indicated that NRZ1 and NRM1 positively regulate coiled-coil domain-containing NLR- and TNL-mediated immunity and function independently of the signaling component Enhanced Disease Susceptibility 1. Furthermore, NRZ1 functions upstream of NRM1 in cell death signaling, and their gene overexpression induces ectopic cell death and expression of NLR signaling components. Our findings uncovered a conserved transcriptional regulatory network that is central to NLR-mediated cell death and immune signaling in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas NLR , Imunidade Vegetal , Fatores de Transcrição , Imunidade Vegetal/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/imunologia , Proteínas NLR/genética , Proteínas NLR/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transdução de Sinais/genética , Doenças das Plantas/virologia , Doenças das Plantas/imunologia , Doenças das Plantas/genética , Morte Celular
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