The Arabidopsis Hypoxia Inducible AtR8 Long Non-Coding RNA also Contributes to Plant Defense and Root Elongation Coordinating with WRKY Genes under Low Levels of Salicylic Acid

AtR8 lncRNA was previously identified in the flowering plant Arabidopsis thaliana as an abundant Pol III-transcribed long non-coding RNA (lncRNA) of approximately 260 nt. AtR8 lncRNA accumulation is responsive to hypoxic stress and salicylic acid (SA) treatment in roots, but its function has not yet been identified. In this study, microarray analysis of an atr8 mutant and wild-type Arabidopsis indicated a strong association of AtR8 lncRNA with the defense response. AtR8 accumulation exhibited an inverse correlation with an accumulation of two WRKY genes (WRKY53/WRKY70) when plants were exposed to exogenous low SA concentrations (20 µM), infected with Pseudomonas syringae, or in the early stage of development. The highest AtR8 accumulation was observed 5 days after germination, at which time no WRKY53 or WRKY70 mRNA was detectable. The presence of low levels of SA resulted in a significant reduction of root length in atr8 seedlings, whereas wrky53 and wrky70 mutants exhibited the opposite phenotype. Taken together, AtR8 lncRNA participates in Pathogenesis-Related Proteins 1 (PR-1)-independent defense and root elongation, which are related to the SA response. The mutual regulation of AtR8 lncRNA and WRKY53/WRKY70 is mediated by Nonexpressor of Pathogenesis-Related Gene 1 (NPR1).

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Systemic Acquired Resistance in Canola Is Linked with Pathogenesis-Related Gene Expression and Requires Salicylic Acid

Phytopathology ◽

10.1094/phyto-97-7-0794 ◽

2007 ◽

Vol 97 (7) ◽

pp. 794-802 ◽

Cited By ~ 29

Author(s):

Shobha D. Potlakayala ◽

Darwin W. Reed ◽

Patrick S. Covello ◽

Pierre R. Fobert

Keyword(s):

Salicylic Acid ◽

Pseudomonas Syringae ◽

Systemic Acquired Resistance ◽

Induced Defense ◽

Acquired Resistance ◽

Microbial Pathogens ◽

Broad Host Range ◽

Avirulent Strain ◽

Enhanced Resistance ◽

Pathogenesis Related

Systemic acquired resistance (SAR) is an induced defense response that confers long-lasting protection against a broad range of microbial pathogens. Here we show that treatment of Brassica napus plants with the SAR-inducing chemical benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) significantly enhanced resistance against virulent strains of the bacterial pathogen Pseudomonas syringae pv. maculicola and the fungal pathogen Leptosphaeria maculans. Localized preinoculation of plants with an avirulent strain of P. syringae pv. maculicola also enhanced resistance to these pathogens but was not as effective as BTH treatment. Single applications of either SAR-inducing pretreatment were effective against P. syringae pv. maculicola, even when given more than 3 weeks prior to the secondary challenge. The pretreatments also led to the accumulation of pathogenesis-related (PR) genes, including BnPR-1 and BnPR-2, with higher levels of transcripts observed in the BTH-treatment material. B. napus plants expressing a bacterial salicylate hydroxylase transgene (NahG) that metabolizes salicylic acid to catechol were substantially compromised in SAR and accumulated reduced levels of PR gene transcripts when compared with untransformed controls. Thus, SAR in B. napus displays many of the hallmarks of classical SAR including long lasting and broad host range resistance, association with PR gene activation, and a requirement for salicylic acid.

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Characterization of long non-coding RNA expression profiles in lymph node metastasis of early-stage cervical cancer

Oncology Reports ◽

10.3892/or.2016.4715 ◽

2016 ◽

Vol 35 (6) ◽

pp. 3185-3197 ◽

Cited By ~ 31

Author(s):

CHUNLIANG SHANG ◽

WENHUI ZHU ◽

TIANYU LIU ◽

WEI WANG ◽

GUANGXIN HUANG ◽

...

Keyword(s):

Cervical Cancer ◽

Lymph Node ◽

Early Stage ◽

Expression Profiles ◽

Rna Expression ◽

Node Metastasis ◽

Non Coding Rna ◽

Early Stage Cervical Cancer ◽

Long Non Coding Rna

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Integrator restrains paraspeckles assembly by promoting isoform switching of the lncRNA NEAT1

Science Advances ◽

10.1126/sciadv.aaz9072 ◽

2020 ◽

Vol 6 (27) ◽

pp. eaaz9072 ◽

Cited By ~ 5

Author(s):

Jasmine Barra ◽

Gabriel S. Gaidosh ◽

Ezra Blumenthal ◽

Felipe Beckedorff ◽

Mina M. Tayari ◽

...

Keyword(s):

Cancer Patients ◽

Cancer Biology ◽

Nuclear Bodies ◽

Physiological Processes ◽

Polyadenylated Rna ◽

Non Coding Rna ◽

Isoform Switching ◽

Low Levels ◽

Lncrna Neat1 ◽

Long Non Coding Rna

RNA 3′ end processing provides a source of transcriptome diversification which affects various (patho)-physiological processes. A prime example is the transcript isoform switch that leads to the read-through expression of the long non-coding RNA NEAT1_2, at the expense of the shorter polyadenylated transcript NEAT1_1. NEAT1_2 is required for assembly of paraspeckles (PS), nuclear bodies that protect cancer cells from oncogene-induced replication stress and chemotherapy. Searching for proteins that modulate this event, we identified factors involved in the 3′ end processing of polyadenylated RNA and components of the Integrator complex. Perturbation experiments established that, by promoting the cleavage of NEAT1_2, Integrator forces NEAT1_2 to NEAT1_1 isoform switching and, thereby, restrains PS assembly. Consistently, low levels of Integrator subunits correlated with poorer prognosis of cancer patients exposed to chemotherapeutics. Our study establishes that Integrator regulates PS biogenesis and a link between Integrator, cancer biology, and chemosensitivity, which may be exploited therapeutically.

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Culturable bacterial microflora associated with nectarine fruit and their potential for control of brown rot

Canadian Journal of Microbiology ◽

10.1139/w10-031 ◽

2010 ◽

Vol 56 (6) ◽

pp. 480-486 ◽

Cited By ~ 16

Author(s):

Wojciech J. Janisiewicz ◽

Jeffrey S. Buyer

Keyword(s):

Pseudomonas Syringae ◽

Early Stage ◽

Acid Methyl Ester ◽

Brown Rot ◽

Monilinia Fructicola ◽

Frequency Of Occurrence ◽

Bacterial Strains ◽

Inoculum Concentration ◽

Stage Of Development ◽

Acid Methyl

Microflora of fruit surfaces have been the best source of antagonists against fungi causing postharvest decay of fruit. However, there is little information on microflora colonizing surfaces of fruits other than grape, apple, and citrus. We characterized bacterial microflora on nectarine fruit surfaces from the early stage of development until harvest. Identification of bacterial strains was made using MIDI (fatty acid methyl ester analysis) and Biolog systems. Biolog identified 35% and MIDI 53% of the strains. Thus results from MIDI were used to determine the frequency of occurrence of genera and species. The most frequently occurring genera were Curtobacterium (21.31%), followed by Pseudomonas (19.99%), Microbacterium (13.57%), Clavibacter (9.69%), Pantoea (6.59%), and Enterobacter (4.26%). The frequency of isolations of some bacteria — for example, the major pseudomonads (Pseudomonas syringae, Pseudomonas putida, and Pseudomonas savastanoi) or Pantoea agglomerans — tended to decline as fruit developed. As Pseudomonas declined, Curtobacterium became more dominant. Time of isolation was a significant factor in the frequency of occurrence of different bacteria, indicating succession of the genera. Throughput screening of the bacterial strains against Monilinia fructicola on nectarine fruit resulted in the detection of strains able to control brown rot. The 10 best-performing antagonistic strains were subjected to secondary screening. Four strains reduced decay severity by more than 50% (51.7%–91.4% reduction) at the high pathogen inoculum concentration of 105conidia/mL.

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Long Non-Coding RNA in the Pathogenesis of Cancers

Cells ◽

10.3390/cells8091015 ◽

2019 ◽

Vol 8 (9) ◽

pp. 1015 ◽

Cited By ~ 72

Author(s):

Chi ◽

Wang ◽

Yu ◽

Yang

Keyword(s):

Early Stage ◽

Gene Expressions ◽

Rna Transcripts ◽

The Past ◽

Non Coding Rna ◽

Incidence And Mortality ◽

Non Coding Rnas ◽

Tumor Growth And Metastasis ◽

New Biomarkers ◽

Long Non Coding Rna

The incidence and mortality rate of cancer has been quickly increasing in the past decades. At present, cancer has become the leading cause of death worldwide. Most of the cancers cannot be effectively diagnosed at the early stage. Although there are multiple therapeutic treatments, including surgery, radiotherapy, chemotherapy, and targeted drugs, their effectiveness is still limited. The overall survival rate of malignant cancers is still low. It is necessary to further study the mechanisms for malignant cancers, and explore new biomarkers and targets that are more sensitive and effective for early diagnosis, treatment, and prognosis of cancers than traditional biomarkers and methods. Long non-coding RNAs (lncRNAs) are a class of RNA transcripts with a length greater than 200 nucleotides. Generally, lncRNAs are not capable of encoding proteins or peptides. LncRNAs exert diverse biological functions by regulating gene expressions and functions at transcriptional, translational, and post-translational levels. In the past decade, it has been demonstrated that the dysregulated lncRNA profile is widely involved in the pathogenesis of many diseases, including cancer, metabolic disorders, and cardiovascular diseases. In particular, lncRNAs have been revealed to play an important role in tumor growth and metastasis. Many lncRNAs have been shown to be potential biomarkers and targets for the diagnosis and treatment of cancers. This review aims to briefly discuss the latest findings regarding the roles and mechanisms of some important lncRNAs in the pathogenesis of certain malignant cancers, including lung, breast, liver, and colorectal cancers, as well as hematological malignancies and neuroblastoma.

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A Long Non-Coding RNA of Citrus tristeza virus: Role in the Virus Interplay with the Host Immunity

Viruses ◽

10.3390/v11050436 ◽

2019 ◽

Vol 11 (5) ◽

pp. 436 ◽

Cited By ~ 5

Author(s):

Sung-Hwan Kang ◽

Yong-Duo Sun ◽

Osama O. Atallah ◽

Jose Carlos Huguet-Tapia ◽

Jerald D. Noble ◽

...

Keyword(s):

Citrus Tristeza Virus ◽

Ectopic Expression ◽

Oxidase Gene ◽

Non Coding Rna ◽

Systemic Spread ◽

Pathogenesis Related ◽

Long Time ◽

Long Non Coding Rna ◽

Tristeza Virus ◽

Citrus Tristeza

During infection, Citrus tristeza virus (CTV) produces a non-coding subgenomic RNA referred to as low-molecular-weight tristeza 1 (LMT1), which for a long time has been considered as a by-product of the complex CTV replication machinery. In this study, we investigated the role of LMT1 in the virus infection cycle using a CTV variant that does not produce LMT1 (CTV-LMT1d). We showed that lack of LMT1 did not halt virus ability to replicate or form proper virions. However, the mutant virus demonstrated significantly reduced invasiveness and systemic spread in Nicotiana benthamiana as well as an inability to establish infection in citrus. Introduction of CTV-LMT1d into the herbaceous host resulted in elevation of the levels of salicylic acid (SA) and SA-responsive pathogenesis-related genes beyond those upon inoculation with wild-type (WT) virus (CTV-WT). Further analysis showed that the LMT1 RNA produced by CTV-WT or via ectopic expression in the N. benthamiana leaves suppressed SA accumulation and up-regulated an alternative oxidase gene, which appeared to mitigate the accumulation of reactive oxygen species. To the best of our knowledge, this is the first report of a plant viral long non-coding RNA being involved in counter-acting host response by subverting the SA-mediated plant defense.

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Identification of Arabidopsis Mutants Exhibiting an Altered Hypersensitive Response in Gene-for-Gene Disease Resistance

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2000.13.3.277 ◽

2000 ◽

Vol 13 (3) ◽

pp. 277-286 ◽

Cited By ~ 37

Author(s):

I-ching Yu ◽

Kevin A. Fengler ◽

Steven J. Clough ◽

Andrew F. Bent

Keyword(s):

Salicylic Acid ◽

Disease Resistance ◽

Pseudomonas Syringae ◽

Hypersensitive Response ◽

Growth Defects ◽

Lesion Mimic ◽

Pathogenesis Related ◽

Lesion Mimic Mutant ◽

Mutant Phenotypes ◽

Temporally Correlated

A mutational study was carried out to isolate Arabidopsis thaliana plants that exhibit full or partial disruption of the RPS2-mediated hypersensitive response (HR) to Pseudomonas syringae that express avrRpt2. Five classes of mutants were identified including mutations at RPS2, dnd mutations causing a “defense, no death” loss-of-HR phenotype, a lesion-mimic mutant that also exhibited an HR¯phenotype, and a number of intermediate or partial-loss-of-HR mutants. Surprisingly, many of these mutants displayed elevated resistance to virulent P. syringae and, in some cases, to Peronospora parasitica. Constitutively elevated levels of pathogenesis-related (PR) gene expression and salicylic acid were also observed. In the lesion-mimic mutant, appearance of elevated resistance was temporally correlated with appearance of lesions. For one of the intermediate lines, resistance was shown to be dependent on elevated levels of salicylic acid. A new locus was identified and named IHR1, after the mutant phenotype of “intermediate HR.” Genetic analysis of the intermediate-HR plant lines was difficult due to uncertainties in distinguishing the partial/intermediate mutant phenotypes from wild type. Despite this difficulty, the intermediate-HR mutants remain of interest because they reveal potential new defense-related loci and because many of these lines exhibit partially elevated disease resistance without dwarfing or other apparent growth defects.

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