Hiv Genome Organization And Structure Essay

Reverse transcriptase is when DNA copies are made of the RNA virus. This allows for the DNA to be integrated with the human cells genome which is later used to make more virus particles by infecting other cells.

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.

CD4 is a glycoprotein found on the surface of immune cells such as T helper cells, monocytes, macrophages, and dendritic cells. HIV infects cells of the immune system called T lymphocytes (T cells) and macrophages. HIV has an envelope and contains two copies of single-stranded RNA as the genome. Within the viral capsid are important viral enzymes called reverse transcriptase, integrase, and protease. The HIV virus has a spike protein that is called gp120, and the host cell receptor is CD4+. HIV belongs to a class of viruses called retroviruses. Retroviruses are RNA viruses, and to replicate or reproduce, they must make a DNA copy of their RNA through transcription and translation. It is the DNA genes that allow the

b. HIV is an incurable disease that relies on coreceptors to initiate host cell interaction and proliferates by utilizing the host cell’s own machinery to reproduce new virus. We will more deeply explore the mechanism in which HIV virions infiltrate and deceive our host cell. In addition, we will discuss current treatment and research that are in the process of finding a highly coveted cure.

* HIV belongs to a group of retroviruses called lentiviruses. The genome of retroviruses is made of RNA, and each virus has two single chains of RNA; for replication, the virus needs a host cell, and the RNA must first be transcribed into DNA, which is done with the enzyme reverse transcriptase.

Riviere, L., Darlix, J., & Cimarelli, A. (2009). Analysis Of The Viral Elements Required In The Nuclear Import Of HIV-1 DNA. Journal of Virology, 729-739. Retrieved October 4, 2014.

The human herpes virus has a diameter of 150 nm. The DNA genome in the core is surrounded by an icosadeltahedral capsid. The capsid contains 162 capsomeres and it is enclosed with an envelope. Several glycoproteins are encoded into the envelope. Between the envelope and the capsid there is a space known as tegument which contains viral proteins and enzymes and it helps in replication

Treatment development focused on limiting the virus' ability to transcribe and replicate copies of itself within the host cell. Reverse transcriptase is an enzyme coded by the virus RNA. Reverse transcriptase (RT) allows the RNA to make a functioning DNA copy that is inserted into the host cell DNA and begin manufacturing copies of new viral RNA identical to the strands in the initial viron. RT is found only in retroviruses and focus on AIDS treatment has been on inhibiting the function of RT in HIV action within a host cell( Furman, P. A. Fyfe, J. A. St.Clair, M. H.; Wenhold, J. Rideout, J. L., Broder, S., Mitsuya, H.; Barry, D. W. 1985).

Retroviruses are a part of a large and diverse family of enveloped RNA viruses. They are defined by common taxonomic denominators that include composition, structure and replicative properties. “The virions are 80–100 nm in diameter, and their outer lipid envelope incorporates and displays the viral glycoprotein’s .The shape and location of the internal protein core are characteristic for various genera of the family. “ (Coffin, John M) The virion RNA is approximately 7–12 kb in size. It is linear, single-stranded, nonsegmented, and of positive polarity. A distinctive feature of this family is its replicative method which involves reverse transcription of the virion RNA into linear double

A virus is a noncellular particle containing a genome that can replicate only inside of a cell (Slonczewski and Foster, 2009). It contains an infective nucleic acid, virion, inside a capsid, which is a protective shell made up of proteins. Some virions have a method of transportation to transfer its genome into the host cell. Most often viral gene transfer mediates the evolution of cell genomes. When a virus infects the host cell, the genome of the virus subverts the host cell to make copies of the virus, which then escape to infect more cells (Slonczewski and Foster, 2009). The bacteriophages T4 and X174 were used because the sizes of them simulates a human pathogen, since a human viral pathogen cannot be used. Bacteriophage T4 is used to mimic a Human Immunodeficiency Virus (HIV) and bacteriophage X174 was used to mimic the Hepatitis C virus.

must take ELISA tests at various intervals after the usual 28 day course of treatment, sometimes

The synthesis of the viral glycoproteins HA & NA starts in the cytoplasm and later these growing polypeptide chains are transported to the endoplasmic reticulum where the proteins are modified and assembled into trimers and tetramers ( Samji T.,2009).These proteins are then transported through the Golgi apparatus and the trans-Golgi network to the plasma membrane of the cell where they inserted finally. The synthesis and folding of viral core proteins occur entirely in the cytoplasm. NP and the RNA polymerase components interact with newly synthesized viral RNA to form RNPs. The M1 protein forms interaction with the C-terminal domains of HA and NA protein on the cell plasma membrane. The newly formed RNPs interact with the M1 protein. This interaction also stops re-entry of RNPs inside the nucleus of the cell. After attachment of RNPs to M1protein where it act as a bridge on the inner half of the cell plasma membranes, in a process of budding, the new virus particles are assembled . The progeny virions bud off from the host cell. (Shi etal.,2014).As soon as budding takes place, the new virions are still attached to the cell surface through interaction of the HA with sialic acid moieties on cellular glycoproteins or glycolipids. The

4,5 The DNA intermediate is integrated into the host chromosome to become a cellular gene. 4,5 This DNA an also serves as a template for viral mRNA and genome RNA synthesis by host cell DNA-dependent RNA polymerase. 4,5,7,8 The retroviral genome consists of three genes that encode polyproteins for Gag (capsid, matrix and nucleic acid binding proteins), Pol (polymerase, protease and integrase) and Env (envelope proteins).

Human immunodeficiency virus is a retrovirus that affects the T cells specifically to the immune system. In spite of, lowering the immunity of humans and claiming the lives of many people around world. H.I.V replication is a multi- stage process and every step is necessary to complete its process. (“T Cell”) In step one, the entry of the virus requires certain receptors from the host cell such as a CD4. In addition, these receptors are composed of two glycoproteins that are embedded in the viral envelope. (“Kestens, P.”) By approaching the target, the cells of a gp120 connects to the CD4 receptors and the transmembrane gp41 is capable of transferring its information into the cell membrane. Uniquely, this process creates a pathway for the virus to fuse with the host cell. When it enters the cell it breaks open and releasing two viral RNA strands and three essential replication enzymes.

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