Anatomy of a Retrovirus and RNA
A retrovirus is a type of virus that uses reverse transcription if its genome to
transfer from RNA to DNA.
Ellerman and Bang first discovered leukemia viruses found in chickens in 1908.
The first pathogenic human retrovirus, Human T-lymphotropic virus, was discovered in
1981.
The different genera of retroviruses are Alpharetrovirus, for example Avian leucosis
virus; Betaretrovirus, for example, Mouse mammary tumour virus;
Gammaretrovirus, for example Feline leukemia virus; Deltaretrovirus, for example
Human T-lymphotropic virus; Epsilonretrovirus, for example Walleye dermal sarcoma virus;
Lentivirus, for example Human immunodeficiency virus 1; Spumavirus, for example
Chimpanzee foamy virus.
Below is a picture of the most well known retrovirus that was discovered in 1983,
human immunodeficiency virus, or HIV.
Courtesy of http://en.wikipedia.org/wiki/Image: Aids_virus.jpg
Anatomy of a Retrovirus
Lipid envelope: a lipid bilayer membrane surrounding the retrovirus derived
rom the source’s plasma membrane.
Receptor binding sites: a surface protein that allows the retrovirus to bind
to a specific type of cell.
RTase: the enzyme reverse transcriptase used to transcribe DNA out of RNA.
Viral RNA: the retroviruses strand of RNA; could be two matching molecules.
Capsid: surrounds and protects RNA.
Courtesy of http://www.accessexcellence.org/RC/VL/GG/diagram.html
Anatomy of RNA
RNA stands for ribonucleic acid. It consists of nucleic acids and particular order of cytosine, guanine, adenine, and uracil. It is used as a template for proteins that are made in the cell.
Courtesy of
http://en.wikipedia.org/wiki/Image:NA-comparedto-DNA_thymineAndUracilCorrected.png
There are several types of RNA that do different jobs in the cell.
mRNA - messenger RNA - takes information transcribed from DNA out of the nucleus to a ribosomes where protein synthesis takes place.
Courtesy of
http://en.wikipedia.org/wiki/Image:MRNA-interaction.png
tRNA - transfer RNA - takes a small chain of RNA to a polypeptide at a ribosome
Courtesy of
Courtesy of Courtesy of http://www.emc.maricopa.edu/faculty/farabee/biobk/cendogma.gif
Courtesy of
http://www.emc.maricopa.edu/faculty/farabee/biobk/cendogma.gif
