This document discusses satellite RNA, which are small non-coding RNAs that depend on helper viruses for replication and encapsidation. It provides 3 key points:
1) Satellite RNAs alter symptoms of their helper viruses. They do not encode their own replication machinery and instead rely on the helper virus and plant cells. This makes them useful for studying helper virus replication.
2) Satellite RNAs can accumulate to high levels and be developed into expression vectors. They compete with helper virus RNA for replication, which can reduce accumulation of the helper virus.
3) Satellite RNAs can modulate or exacerbate disease symptoms depending on their sequence and interaction with the helper virus strain and host plant. They may attenuate symptoms
CaMV Genome organization & their replication, Cauliflower Mosaic Virus belong to Group VII (ds-DNA-RT), Open circular double stranded DNA of 80kb and CaMV replicates by reverse transcription
in this chapter covers the symptoms modulation and diseases severity increases and decreases. and role of SiRNA in diseases severity reduction. and also covers the types of SRNA..
inroduction:Plant viruses are viruses that affect plants.
Pathogenic to higher plants.
. Harmless to human and other animals.
Reduce plant crop yield and quality of crops.
Some may be able to multiply within the bodies
Of aphids and nematodes.
History:Beijernick ( 1897) coined the latin name “VIRUS” meaning Poison. He studied plant juices and found they caused healthy plants to become sick.
Wendell Stanley (1935) crystallized sap from sick Tobacco plants. He discovered viruses were made of nucleic acids and proteins.
Geminivirus:one of the family of plant virus.
Currently over 360 species in this family, divided among 9 genera.
Diseases associated with this family include bright yellow mosaic , yellow mosaic, yellow mottle, leaf curling, stunting, streaks, reduced yields.
Ss circular dna diverge in both directions from a virion strand origin of replication (AMBISENSE).
Virus Classification:Group – Group II (ssDNA)
Order - Unassigned
Family - Geminiviridae
Genera – Becurtovirus Grablovirus
Begomovirus Mastrevirus
Capulavirus Topocuvirus
curtovirus Turncurtovirus
Eragrovirus
Structure: have Circular single-stranded DNA.
Genome is either in two segments.
The non-segmented genome is 2500-3000 nucleotides long, and the segmented genome is 4800-5600 nucleotides long.
The genome encodes for both structural and non-structural proteins.
In geminivirus, both segments must be transmitted to the host for a full systemic infection to occur.
Virion Sturcture:Geminivirus are non-enveloped, icosahedral virions that consists of a capsid.
The capsid is germinate, or twinned, and consists of 22 Capsomers.
The capsid is 30nm long and has a diameter of 18-20nm.
Symptoms:the time of infection, the virus strains and the presence of mixed infections.
Common symptoms are stunting, curling, and twisting of leaves.
Short internodes and stunted appearance , no apical growth caused by early infection.
Replication:Geminivirus encodes only a few proteins, thus they need to dependent host cell factors for replication.
These factors are DNA polymerase and repair polymerase to amplify their genome.
Replicate by a rolling circle mechanism like bacteriophages such as M13, and many plasmids.
INTRODUCTION:
The first plant virus shown to have a DNA genome and the first shown to replicate by reverse transcription.
Worldwide but only causes significantly losses locally.
It is transmitted by aphids .
Type member of the Caulimovirus genus, contains 11 species and 6 possible members.
significantly impact on plant virology and plant molecular biology.
The virus is an important source of gene regulatory elements, used exclusively in the genetic manipulation of plants.
STRUCTURE:Icosachedral with a diameter of 52Â nm built from 420 capsid protein subunits.
It contains a circular double-stranded DNA molecule of about 8.0 kB .
Dna is interrupted by sitespecific discontinuties resulting from its replication by reverse transcription.
After entering the host, the single stranded nicks in the viral DNA are repaired, forming a supercoiled molecule that binds to histones.
DNA is transcriped into a full length .
Replication
Risk Factors:The Cauliflower mosaic virus promoter (CaMV 35S) is used in most transgenic crops to activate foreign genes which have been artificially inserted into the host plant. It is inserted into transgenic plants in a form which is different from that found when it is present in its natural Brassica plant hosts. This enables it to operate in a wide range of host-organism environments which would otherwise not be possible.
CaMV Genome organization & their replication, Cauliflower Mosaic Virus belong to Group VII (ds-DNA-RT), Open circular double stranded DNA of 80kb and CaMV replicates by reverse transcription
in this chapter covers the symptoms modulation and diseases severity increases and decreases. and role of SiRNA in diseases severity reduction. and also covers the types of SRNA..
inroduction:Plant viruses are viruses that affect plants.
Pathogenic to higher plants.
. Harmless to human and other animals.
Reduce plant crop yield and quality of crops.
Some may be able to multiply within the bodies
Of aphids and nematodes.
History:Beijernick ( 1897) coined the latin name “VIRUS” meaning Poison. He studied plant juices and found they caused healthy plants to become sick.
Wendell Stanley (1935) crystallized sap from sick Tobacco plants. He discovered viruses were made of nucleic acids and proteins.
Geminivirus:one of the family of plant virus.
Currently over 360 species in this family, divided among 9 genera.
Diseases associated with this family include bright yellow mosaic , yellow mosaic, yellow mottle, leaf curling, stunting, streaks, reduced yields.
Ss circular dna diverge in both directions from a virion strand origin of replication (AMBISENSE).
Virus Classification:Group – Group II (ssDNA)
Order - Unassigned
Family - Geminiviridae
Genera – Becurtovirus Grablovirus
Begomovirus Mastrevirus
Capulavirus Topocuvirus
curtovirus Turncurtovirus
Eragrovirus
Structure: have Circular single-stranded DNA.
Genome is either in two segments.
The non-segmented genome is 2500-3000 nucleotides long, and the segmented genome is 4800-5600 nucleotides long.
The genome encodes for both structural and non-structural proteins.
In geminivirus, both segments must be transmitted to the host for a full systemic infection to occur.
Virion Sturcture:Geminivirus are non-enveloped, icosahedral virions that consists of a capsid.
The capsid is germinate, or twinned, and consists of 22 Capsomers.
The capsid is 30nm long and has a diameter of 18-20nm.
Symptoms:the time of infection, the virus strains and the presence of mixed infections.
Common symptoms are stunting, curling, and twisting of leaves.
Short internodes and stunted appearance , no apical growth caused by early infection.
Replication:Geminivirus encodes only a few proteins, thus they need to dependent host cell factors for replication.
These factors are DNA polymerase and repair polymerase to amplify their genome.
Replicate by a rolling circle mechanism like bacteriophages such as M13, and many plasmids.
INTRODUCTION:
The first plant virus shown to have a DNA genome and the first shown to replicate by reverse transcription.
Worldwide but only causes significantly losses locally.
It is transmitted by aphids .
Type member of the Caulimovirus genus, contains 11 species and 6 possible members.
significantly impact on plant virology and plant molecular biology.
The virus is an important source of gene regulatory elements, used exclusively in the genetic manipulation of plants.
STRUCTURE:Icosachedral with a diameter of 52Â nm built from 420 capsid protein subunits.
It contains a circular double-stranded DNA molecule of about 8.0 kB .
Dna is interrupted by sitespecific discontinuties resulting from its replication by reverse transcription.
After entering the host, the single stranded nicks in the viral DNA are repaired, forming a supercoiled molecule that binds to histones.
DNA is transcriped into a full length .
Replication
Risk Factors:The Cauliflower mosaic virus promoter (CaMV 35S) is used in most transgenic crops to activate foreign genes which have been artificially inserted into the host plant. It is inserted into transgenic plants in a form which is different from that found when it is present in its natural Brassica plant hosts. This enables it to operate in a wide range of host-organism environments which would otherwise not be possible.
he rhizosphere is the narrow region of soil or substrate that is directly influenced by root secretions and associated soil microorganisms known as the root microbiome.
The phyllosphere is a term used in microbiology to refer to the total above-ground portions of plants as habitat for microorganisms.
Soil organic matter has long been recognized as one of the most important components in maintaining soil fertility, soil quality, and agricultural sustainability. The soil zone strongly influenced by plant roots, the rhizosphere, plays an important role in regulating soil organic matter decomposition and nutrient cycling. Processes that are largely controlled or directly influenced by roots are often referred to as rhizosphere processes. These processes may include exudation of soluble compounds, water uptake, nutrient mobilization by roots and microorganisms, rhizosphere-mediated soil organic matter decomposition, and the subsequent release of CO2 through respiration. Rhizosphere processes are major gateways for nutrients and water. At the global scale, rhizosphere processes utilize approximately 50% of the energy fixed by photosynthesis in terrestrial ecosystems, contribute roughly 50% of the total CO2 emitted from terrestrial ecosystems, and mediate virtually all aspects of nutrient cycling. Therefore, plant roots and their rhizosphere interactions are at the center of many ecosystem processes. However, the linkage between rhizosphere processes and soil organic matter decomposition is not well understood. Because of the lack of appropriate methods, rates of soil organic matter decomposition are commonly assessed by incubating soil samples in the absence of vegetation and live roots with an implicit assumption that rhizosphere processes have little impact on the results. Our recent studies have overwhelmingly proved that this implicit assumption is often invalid, because the rate of soil organic matter decomposition can be accelerated by as much as 380% or inhibited by as much as 50% by the presence of live roots. The rhizosphere effect on soil organic matter decomposition is often large in magnitude and significant in mediating plant-soil interactions.
Bacteriophages & Its classification, cycles, therapy, and applicationsZoqiaTariq
These slides are covering multiple aspects of Bacteriophages including History
Classification
Replication
Plaque Assay
Transduction
Phage Therapy and pahge types.
TOBACCO MOSAIC VIRUS (Genome organization &their replication) TMV is a plant virus which infects a wide range of plants, especially tobacco and other members of the family Solanaceae and cucumbers, and a number of ornamental flowers.
tobacco mosaic virus in tobacco-significance of TMV, Economic loss of TMV, distribution of TMV, disease cycle of TMV, Favourable condition of TMV, Protein synthesis and RNA replication of TMV,infection process and life cycle of TMV, Disease management of TMV in tobacco plants
In this presentation you will be learning about the SPOTTED WILT VIRUSES which is caused in TOMATO crop. And also its mode of establishment into the crop, deficiency symptoms, life cycle, life span of the virus, yield losses in that particular crop and at last its MANAGEMENT PRACTICES.
he rhizosphere is the narrow region of soil or substrate that is directly influenced by root secretions and associated soil microorganisms known as the root microbiome.
The phyllosphere is a term used in microbiology to refer to the total above-ground portions of plants as habitat for microorganisms.
Soil organic matter has long been recognized as one of the most important components in maintaining soil fertility, soil quality, and agricultural sustainability. The soil zone strongly influenced by plant roots, the rhizosphere, plays an important role in regulating soil organic matter decomposition and nutrient cycling. Processes that are largely controlled or directly influenced by roots are often referred to as rhizosphere processes. These processes may include exudation of soluble compounds, water uptake, nutrient mobilization by roots and microorganisms, rhizosphere-mediated soil organic matter decomposition, and the subsequent release of CO2 through respiration. Rhizosphere processes are major gateways for nutrients and water. At the global scale, rhizosphere processes utilize approximately 50% of the energy fixed by photosynthesis in terrestrial ecosystems, contribute roughly 50% of the total CO2 emitted from terrestrial ecosystems, and mediate virtually all aspects of nutrient cycling. Therefore, plant roots and their rhizosphere interactions are at the center of many ecosystem processes. However, the linkage between rhizosphere processes and soil organic matter decomposition is not well understood. Because of the lack of appropriate methods, rates of soil organic matter decomposition are commonly assessed by incubating soil samples in the absence of vegetation and live roots with an implicit assumption that rhizosphere processes have little impact on the results. Our recent studies have overwhelmingly proved that this implicit assumption is often invalid, because the rate of soil organic matter decomposition can be accelerated by as much as 380% or inhibited by as much as 50% by the presence of live roots. The rhizosphere effect on soil organic matter decomposition is often large in magnitude and significant in mediating plant-soil interactions.
Bacteriophages & Its classification, cycles, therapy, and applicationsZoqiaTariq
These slides are covering multiple aspects of Bacteriophages including History
Classification
Replication
Plaque Assay
Transduction
Phage Therapy and pahge types.
TOBACCO MOSAIC VIRUS (Genome organization &their replication) TMV is a plant virus which infects a wide range of plants, especially tobacco and other members of the family Solanaceae and cucumbers, and a number of ornamental flowers.
tobacco mosaic virus in tobacco-significance of TMV, Economic loss of TMV, distribution of TMV, disease cycle of TMV, Favourable condition of TMV, Protein synthesis and RNA replication of TMV,infection process and life cycle of TMV, Disease management of TMV in tobacco plants
In this presentation you will be learning about the SPOTTED WILT VIRUSES which is caused in TOMATO crop. And also its mode of establishment into the crop, deficiency symptoms, life cycle, life span of the virus, yield losses in that particular crop and at last its MANAGEMENT PRACTICES.
RNA silencing is an ancient eukaryotic pathway in which double stranded RNA (dsRNA) triggers destruction of related RNAs in the cell.This study focuses on the currently known plant virus encoded suppressors of silencing and the functional assays used to identify these proteins. Because they interfere with silencing at different points in the pathway, these viral suppressors are powerful tools to help unravel the mechanism of RNA silencing in plants.
INTERFERENCE means the act of interfering with something, here, with RNA. RNAi is an evolutionarily conserved mechanism triggered by dsRNA molecules, to prevent the expression of specific genes or the translation, causes sequence-specific degradation of the targeted mRNA molecules of that particular gene. It was also known as CO-SUPPRESSION, POST TRANSCRIPTIONAL GENE SILENCING [PTGS] in plants and QUELLING in fungi.
Antisense RNA Technology for crop improvement.pptxSanyamPatel2
Improvement of crops by following genetic engineering techniques:
Gene silencing
Post transcription silencing
Post translation silencing
Antisense RNA
RNA interference
The overall description of major diseases of Rice or Paddy crop is ellustrated in presentation. The students prepairing for Agriculture can feel helpful. Thank You!
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
1. SAM HIGGINGBOTTOM UNIVRSITY OF AGRICULTURE,
TECHNOLOGY & SCIENCES, PRAYAGRAJ.
PRESENTED BY :
DESHMUKH TUSHAR SHIVAJI
ID NO.18MSENT078
M. SC (Ag) ENTOMOLOGY.
PRESENTED TO:
DR. SHASHI TIWARI.
1
3. What is Satellite RNA:
• Satellite RNAs are replicated by the helper virus replicase
complex and encapsidated by helper virus.
• Typically, they share no nucleotide
sequence homology with their helper virus. An
exception to this is the satellite RNA of TCV, which
contains a sequence domain with homology to
TCV RNA.
• This satellite RNA therefore has some
characteristics in common with defective RNAs.
3
4. Why we are concentrating on sat RNA?
• It alters the symptoms .
• They do not encode their own RdRps & depends on helper virus and
plant machineries.
• It provides additional information to study the replication of helper virus. It
act as a Molecular Parasites. So that reduce the accumulation of their
helper viral RNAs .
• They can accumulate to high levels in host plants and thus in some cases
can be developed into high-level expression vectors for foreign genes.
Kaper,j.M et al.. 1977: Mossop,d.W . et al .. 1979 :
4
5. Classification:
Satellite RNA
ssRNA
Large
satRNA
satBaMV, TBRV
satRNA, satGFLV,
satArMV,
Small linear
satRNA
PSV satRNA, TCV
satRNA, CMV satRNA,
TBSV satRNA.
Small circular
satRNA
TobRV satRNA, SNMV
satRNA , CYDV
satRNA ,
dsRNA
Saccharomyces
cerevisiae M virus
satellite,
Trichomonas
vaginalis T1 virus
satellite
NCBI, taxonomy ID :12877
https://en.wikipedia.org/wiki/Satellite_%28biology%29#Classification
5
6. PROTEIN FUCTIONS :
TBRV satRNA are encode Mr 48,000 protein (419-424 AA) - in vivo -
involved in replication.
The P3 protein encoded by a GFLV-F13 satRNA (1,114 nt) -
replication .
satArMV - in planta - replication .
The P20 protein encoded by BaMV satRNA is not essential for
replication but is involved in the systemic movement of satBaMV
RNA.
Hans,f et.al..1993: Palani.pv et.al..2006,
6
8. REPLICATION
Helper virus specificity :
SNMV does not support the replication of satellite RNA of LTSV,
even though LTSV does support the replication of both satRNAs
Host specificity :
The small satellite RNA of ArMV replicates very efficiently in
Chenopodium quinoa by contrast TBRV replicates poorly in C. quinoa
but replicates very efficiently in Nicotiana clevelandii and Petunia
hybrida .
Enzymology :
A membrane-bound RdRp complex was isolated from tobacco
protoplasts inoculated with RNAs 1 and 2 of CMV; this complex was
capable of synthesizing CMV and satellite ds RNAs in vitro .
Davis, c et al .,1990 :Jones, A. T et al .,1984
8
9. Symptom modulation :
Interaction of SatRNA , Helper Virus , Host..,
Symptom attenuation can attained by reduction in virus titer through
competition for the replicase between the satellite and helper virus
(Strain).
changes in the nucleotides sequence of sat RNA are affect the
pathogenicity in host specific manner.
Example : (CMV sat RNA )
Chlorosis – 135-175 nt.
Necrosis - 290-310 nt.
Masuta c,et al..,1989: Sleat d. et al..,1990:
9
10. Exacerbated symptoms:
The CP of TCV suppresses RNA silencing in N. benthamiana.
TCV CP is a weak suppressor of RNA silencing when assembled into
the intact virions but a strong suppressor when expressed freely in the
cytosol.
The satC associated with TCV can reduce the accumulation of virions,
thereby increasing the level of free CP, which leads to the suppression
of RNA silencing and subsequent exacerbation in symptom severity.
Zhang F et al..,2003: Manfre A.J et al..2008
10
11. That siRNAs derived from a CMV satRNA can induce RNA silencing
against the CMV helper virus.
They showed that an abundant sat-siRNA, derived from the small
region conserved between satRNA and 3′ UTRs of CMV, can target the
homologous 3′ UTR sequence of CMV-inducing RDR6-dependent RNA
silencing against CMV.
Using a green florescent protein (GFP) sensor construct, they
confirmed sat-siRNA-directed cleavage at the CMV 3′ UTR sequence.
Thus, sat-siRNAs can have a direct role in reducing helper virus
accumulation by directing cross silencing against the helper virus
genome.
Zhu et al. 2011
RNA silencing : 11
12. To counter the defense
system of host plants, RNA
encodeviruses usually
proteins that function as
of RNAsuppressors
silencing.
The CP of TCV suppresses
RNA silencing in N.
benthamiana by
the Dicer-like
obstructing
protein
silencingDCL2/DCL4
pathway.
Manfre A.J et al..2008
12
14. References and Notes:
1. Murant AF, Mayo MA. Satellites of plant viruses. Annu Rev
Phytopathol. 1982;20:49–70.
2. Tien P, Wu GS. Satellite RNA for the biocontrol of plant disease. Adv Virus
Res. 1991;39:321–39
3. Roossinck MJ, Sleat D, Palukaitis P. Satellite RNAs of plant viruses:
structures and biological effects. Microbiol Rev. 1992;56:265–79. [PMC free
article] [PubMed] [Google Scholar]
4. Garcia-Arenal F, Palukaitis P. Structure and functional relationships of
satellite RNAs of cucumber mosaic virus. Curr Top Microbiol
Immunol. 1999;239:37–63.
5. Simon AE, Roossinck MJ, Havelda Z. Plant virus satellite and defective
interfering RNAs: new paradigms for a new century. Annu Rev
Phytopathol. 2004;42:415–37.
6. Kaper JM, Waterworth HE. Cucumber mosaic virus associated RNA 5:
causal agent for tomato necrosis. Science. 1977;196:429–
431. [PubMed] [Google Scholar]
14