Search results
Results from the WOW.Com Content Network
A retrovirus is a type of virus that inserts a DNA copy of its RNA genome into the DNA of a host cell that it invades, thus changing the genome of that cell. [2] After invading a host cell's cytoplasm , the virus uses its own reverse transcriptase enzyme to produce DNA from its RNA genome, the reverse of the usual pattern, thus retro (backward).
The general retrovirus genome consists of three genes vital for the invasion, replication, escape, and spreading of its viral genome. These three genes are gag (encodes for structural proteins for the viral core), pol (encodes for reverse transcriptase, integrase, and protease), and env (encodes for coat proteins for the virus's exterior).
Identical LTR sequences at either end of a retrotransposon. A long terminal repeat (LTR) is a pair of identical sequences of DNA, several hundred base pairs long, which occur in eukaryotic genomes on either end of a series of genes or pseudogenes that form a retrotransposon or an endogenous retrovirus or a retroviral provirus.
An endogenous retrovirus is a retrovirus without virus pathogenic effects that has been integrated into the host genome by inserting their inheritable genetic information into cells that can be passed onto the next generation like a retrotransposon. [8] Because of this, they share features with retroviruses and retrotransposons.
The human immunodeficiency viruses (HIV) are two species of Lentivirus (a subgroup of retrovirus) that infect humans.Over time, they cause acquired immunodeficiency syndrome (AIDS), [1] [2] a condition in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. [3]
Bacteriophage vectors are also commonly used in molecular biology. [69] For instance, bacteriophage vectors are used in phage-assisted continuous evolution, promoting rapid mutagenesis of bacteria. [70] Although limited to mycobacteriophages and some phages of gram-negative bacteria, bacteriophages can be used for direct cloning. [71]
The escape hypothesis did not explain the complex capsids and other structures on virus particles. The virus-first hypothesis contravened the definition of viruses in that they require host cells. [27]: 24 Viruses are now recognised as ancient and as having origins that pre-date the divergence of life into the three domains.
Lentivirus is a genus of retroviruses that cause chronic and deadly diseases characterized by long incubation periods, in humans and other mammalian species. [2] The genus includes the human immunodeficiency virus (HIV), which causes AIDS.