P1 / Hc Pro Of The Potyvirus Targets

The biological significance of this article is due in part to the fact that viruses are being considered as partway-living things. Even though they are only halfway living, per se, they are still an important part of the study of living things because of the unique way in which they “live” and continue to reproduce by taking advantage of host cells. The information in this article relates to biologists in that viruses provide an entirely different element of potential life, as they are a cause for reconsideration when it comes to defining and determining life and non-life forms. This

* Flaviviruses: share a common size (40-60nm), symmetry (enveloped, icosahedral nucleocapsid), nucleic acid (positive-sense, single stranded RNA approximately 10,000-11,000 bases), and appearance in the electron microscope. Therefore, images of West Nile virus are representative for this group of viruses.

Viruses are microscopic particles that invade and take over both eukaryotic and prokaryotic cells. They consist of two structures, which are the nucleic acid and capsid. The nucleic acid contains all genetic material in the form of DNA or RNA, and is enclosed in the capsid, which is the protein coating that helps the virus attach to and penetrate the host cell. In some cases, certain viruses have a membrane surrounding the capsid, called an envelope. This structure allows viruses to become more stealthy and protected. There are two cycles in which a virus can go into: lytic and lysogenic. The lytic cycle consists of the virus attaching to a cell, injecting its DNA, and creating more viruses, which proceed to destroy the host. On the other hand, the lysogenic cycle includes the virus attaching to the cell, injecting its DNA, which combines with the cell’s DNA in order for it to become provirus. Then, the provirus DNA may eventually switch to the lytic cycle and destroy the host.

RNA interference, or RNAi, is a biological process in which RNA molecules reduce the gene expression of an organism. This is done typically by causing the destruction of specific mRNA molecules. RNAs are direct products of genes, these small RNAs can bind to other mRNA molecules to either increase or decrease their activity like in the example of preventing an mRNA from producing a protein. There are two types of RNA molecules that are central to RNAi, these molecules are, micro RNA (miRNA) and small interfering RNA (siRNA).

RSV belongs to the paramyxovirus family of viruses. The virion encompasses a helical nucleocapsid packaged in a lipoprotein envelope attained from the host cell plasma membrane during budding. The external surface of the envelope contains a periphery of surface spikes.

On encountering a host cell, the retrovirus attaches itself to receptors on the surface of the host cell’s membrane. Once inside the cell, the capsid opens, releasing RNA and reverse transcriptase into the cell’s cytoplasm.

The virus fuses with the cell’s plasma membrane. The capsid proteins are removed, releasing the viral proteins and RNA. Reverse transcriptase catalyzes the synthesis of a DNA strand complementary to the viral RNA. Reverse transcriptase catalyzes the synthesis of a second DNA strand complementary to the first. The double-stranded DNA is incorporated as a provirus into the cell’s DNA. Proviral genes are transcribed into RNA molecules, which serve as genomes for the next viral generation and as mRNAs for translation into viral proteins. The viral proteins include capsid proteins and reverse transcriptase (made in the cytosol) and envelope glycoproteins (made in the ER). Vesicles transport the glycoproteins from the ER to the cell’s plasma membrane. Capsids are assembled around viral genomes and reverse transcriptase molecules. New viruses bud off from the host cell.

In the article, we learn the Cache Valley virus is spreading quickly through mosquitos. In this unit we learned that viruses with RNA in their nucleic acid reproduce a lot faster than viruses that have DNA in their nucleic acid, therefore the Cache Valley virus probably has RNA in its nucleic acid. Throughout the unit we learned viruses can spread through many types of mediums such

RSV is caused by TLR3 activation. It initiates infections by binding to a cellular receptor and then the viral envelope fuses with the plasma membrane. The virus attaches the cell through the main protein, the G protein and fuses with the plasma membrane of the host cell through the F protein. After penetration, the nucleocapsid of the virus is released into the cytoplasm where replication occurs (3). The viral RNA is like a template for mRNA (3). The mRNA’s job is to translate the viral proteins and complementary RNA serves as a template for virion RNA

Step 1: How will you identify the “vital” cellular protein that the virus targets for degradation? (Hint: think proteomics). (3 pts.)

Chikungunya is a small spherical enveloped virion that measures up 60 to 70nm in diameter. It contains a single strand positive-sense RNA genome (Solignat, Maxime 2009). The virus has a lipid bilayer containing heterodimeric protein spikes composed of two major surface envelope glycoproteins E1 and E2 (Understanding the alpha virus). The genome extends approximately 12 kb long, and is organized in a 5’ cap -untranslated region (UTR), non-structural proteins (nsP1-4), structural proteins (C-E3-E2-6 K-E1), and a 3’ polyA tail end( Microbes and Infection). The structural proteins of the virus are created by the translation of a messenger RNA (mRNA). The 5’ end cap of the genome has a 7- methyl guanosine cap, whereas the 3’ end is polyadenylated

The protective capsid helps the virus escape detection and destruction during the invasion of the host. When the virus reaches the target cell, biochemical reactions between the capsid and cell wall allow the virus to latch on and inject its genome into the cell’s interior. Once inside, the viral genetic material insinuates itself into the host’s DNA or RNA. In an efficient feat of natural bioengineering, the host cell’s genetic machinery now does the rest of the work for the virus. The cell, which had already been making copies of its own genome, now also replicates that of the virus. Coded within the viral material is the blueprint for making more copies of the viral genome. Further instructions command the production of capsids and directions for assembly of new viruses. After the host cell becomes engorged with viruses, it explodes, sending the new

The HIV-1 virion is approximately 120 nm in diameter, roughly spherical, and is composed of two copies of a single stranded positive sense RNA enclosed by a capsid (24). The HIV-1 genome is less than 10 kb and encodes for more than nine different gene products. It encodes for 3 major structural protein genes: gag (group-specific antigen), pol (DNA polymerase), and env (Envelope), which code for major structural proteins and essential enzymes. Gag generates the mature Gag protein matrix (MA or p17), capsid (CA or p24), nucleocapsid (NC or p7), and p6, which encompass proteins for the basic infrastructure of the virus such as the inner core of the viral particle (25). Pol encodes for reverse transcriptase (RT), which enables the virus to reproduce, integrase (IN), which is necessary to integrate the viral double stranded DNA into the host genome, RNAse H, and HIV protease, which are all encapsulated in the core of the inner particle formed by the viral capsid protein p24 (25). Env encodes for glycoproteins of the outer membrane such as outer gp120 (which enables the virus to attach and fuse to cells of the host), and transmembrane gp41 that anchors the glycoprotein complex to the surface of the virion (25). Between the core and the envelope is the HIV matrix proteins which are composed of the viral protein p17 (23). HIV-1 also encodes for proteins with important regulatory elements (tat (Trans-Activator of Transcription) and rev

The similarity between the poliovirus and already solved plant virus’s led to a better understanding of how the poliovirus can regenerate within a host. Although the virus was similar to other plant viruses. The poliovirus was covered with more elaborate loops that are the site of monoclonal antibody escape mutations (Hogle, Chow and 229: 1358-1365Filman, Science). Individual proteins of the virus particle are produced by proteolytic cleavages from a larger precursor, yet the amino and carboxy-termini produced by proteolysis are very distinct. By noting this, Hogle and his team were able to conclude that proteolysis was not just making a lot of proteins from one gene, it is also controlling the timing of assembly (Hogle, Chow and Filman, Science 229: 1358-1365).

The virus responsible for rhizomania, beet necrotic yellow vein virus (BNYVV) is vectored by an