Firstly, the poliovirus enters the host cells by binding to its receptor that is identified to be CD155, a glycoprotein of the immunoglobin superfamily, Once multiple cirus particles bind to the V-type domains of the receptors, these particles would have a conformational change in which they externalizes proteins VP4 and VP1 that is found on the capsid of the virus.
Proteins are then inserted into the cell membrane and forms a pathway where viral particles are internalized. The RNA genome is quickly released into the cytoplasma through a pore. [0]
RECAP:
As a positive-sense ssRNA, its first step of viral replication is to make early proteins. An RNA-dependent RNA polymerase (RdRp) is a protein that uses the virus present RNA as a template to make more RNA.
The RdRp copies the positive-sense RNA strand to make a double-stranded RNA replicative complex and this complementary negative-sense RNA is used as a guide to make more positive-sense ssRNA.
These positive-sense ssRNA can then be used as mRNA to make structural proteins or packaged into final virions. The final step displays the structural proteins and the positive-sense ssRNA being packaged together to exit the cell as it lyses. [2]
Pathway in the body:
The virus enters through the mouth normally and multiplies in the throat and GIT before moving into the bloodstream and carried to the Central Nervous System where is replicates further and destroys the motor neuron cells. Motor neurons control the muscles for swallowing, circulation, respiration, and the trunk of arms and legs.
References:
[0]Poliomyelitis. (n.d.). Retrieved July 31, 2015, from https://microbewiki.kenyon.edu/index.php/
[2]Viral Replication Strategy in Positive-Sense Single-Stranded RNA Viruses - Library. (2010, August 11). Retrieved July 31, 2015, from http://www.microbelibrary.org/library/virus/2781-viral-replication-strategy-in-positive-sense-single-stranded-rna-viruses
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