Phospholipid synthesis fueled by lipid droplets drives the. A world map depicting polioendemic countries, regions of recent outbreak of poliovirus, and countries at high risk of poliovirus outbreak is depicted as figure 1. Poliovirus, the causative agent of polio also known as poliomyelitis, is a member virus of enterovirus c, in the family of picornaviridae. Many individuals acquire infection with polio virus, experience headches, stiff nec and irritability, a form of encephalitis. May 14, 2014 for more information, log on to download the study materials here this.
One way the human immune system protects itself is by producing antibodies that engage the protein covering of the poliovirus, preventing the virus from interacting with another cell. Poliovirus is composed of an rna genome and a protein capsid. Children younger than 5 years old are more likely to contract the virus than. Nonpolio enteroviruses are responsible for significant and frequent illnesses in infants and children and result in protean clinical manifestations. Virus infection as a function of the host cell life cycle. It is initiated by binding of a poliovirion to the cell surface macromolecule cd155, which functions as the receptor 1. Inhibition of pc synthesis restores neutral lipid synthesis in infected cells but does not significantly affect the first cycle of poliovirus replication. Future studies promise to provide detailed insights into the conformational dynamics of the virion during its life cycle. Next, the virus is uncoated within the cytoplasm of the cell when the capsid is removed. Polio also known as poliomyelitis is a highly contagious disease caused by a virus that attacks the nervous system.
The nonpolio enteroviruses are positive strand rna viruses. However, several stages in the virus life cycle are promising targets for therapeutic intervention. World health organization european region was declared polio free of the 3 types of wild poliovirus types 1, 2, and 3 in june 2002. Unlike other rna genome viruses, picornavirus doesnt contain a 7 methyl guanosine cap at the 5end intead they contain vpg a viral protein linked at the 5. Molecular analysis of virulent determinants of enterovirus 71. It is initiated by attachment of the poliovirion to the nterminal vtype immunoglobulinlike domain of its cell surface receptor, the human pv. There are three wild types of poliovirus wpv type 1, type 2, and type 3. All viruses should be going through the same step in the viral replication cycle at the same time figure 31. The negativestrand rna is transiently made during viral genome replication, resulting in doublestrand rna intermediates. These precursors are processed by the 3cpro into mature peptides. This animation describes the structure of the hiv virus, receptormediated attachment to.
Summary the rates of synthesis and final yields of poliovirus rna varied considerably during the four main phases g1, s, g2 and m of the life cycle of. Modlin, in mandell, douglas, and bennetts principles and practice of infectious diseases eighth edition, 2015. Most vaccineassociated cases are due to type 3 or 2. Feb 26, 2019 poliovirus is a member of the picornavirus family, which also includes rhinoviruses, coxsackieviruses, echoviruses, enteroviruses, and hepatitis a virus. We construct a mathematical model of the withincell replication of poliovirus, a prototypic rna virus, and use realistic parameter estimates to describe the. The life cycle of bacteriophages has been a good model for understanding how viruses affect the cells they infect, since similar processes have been observed for eukaryotic viruses, which can cause immediate death of the cell or establish a latent or chronic infection. The genome is a singlestranded positive sense rna genome that is about 7500 nucleotides long. Download this pdf file to color in the life cycle of the poliovirus. Jun 04, 2015 replication cycle of poliovirus, annotated with references to key findings during the past 65 years. Download scientific diagram the cellular life cycle of poliovirus. The growth cycle of type 1 poliovirus in suspended monkey kidney cell populations is characterized.
Schematic diagram of the life cycle of poliovirus within a cell. Poliovirus is a member of the picornaviridae virus family characterized by small isometric particles, 30nm in diameter, containing a single molecule of single stranded rna. One protomer has been moved to show the locations of the attenuating mutation at residue 91 of vp3 pale blue and suppressors white in vp2 residues 215 and 265 and vp3 residues 108, 175 and 178 which lie at the interface between. Enteroviruses are a genus of positivesense singlestranded rna viruses associated with several human and mammalian diseases. The entire poliovirus replication cycle is depicted in fig. The asyn chronous response of hela cells multiply infected with type 1 polio virus. Poliovirus belongs to the family of picornaviruses. Small, icosahedral 2730nm dia nonenveloped particle single stranded rna as genome, 7500 nt serves as messenger rna in infected cells capsid made of 4 proteins. Despite significant progress made in combating poliovirus spread in the u. Figure polio spreads in areas of poor sanitation, such as the community pictured above 21 figure 14. Picornavirus life cycle and processing of proteins. Global polio cases have fallen by 89 since 2005, 66 in 2012 alone. Feb 26, 2019 poliovirus is a member of the family of picornavirus.
Poliovirus, an enterovirus with antigenic types 1,2,3. These diverse viruses cause a variety of diseases, including nonspecific febrile illness, handfootandmouth disease, neonatal sepsislike disease, encephalitis, paralysis and respiratory diseases. The 3 serotypes of poliovirus carry are antigenically distinct. Doctors give unbiased, trusted information on the relationship of polio and infantile paralysis. The replication cycle of poliovirus is initiated by binding to the cell surface receptor. The life cycle begins with the penetration of the virus into the host cell. Picornaviruses are small, etherinsensitive viruses with an rna genome. Poliomyelitis is an acute communicable disease of humans caused by a human enterovirus of the picornaviridae family. To complete the life cycle of the virus, viral proteins are involved in viral replication and translation, in addition to altering host functions, such as cellular gene expression, protein localization, signal. Picornaviruses are small, about 300 angstroms in diameter, and are comprised of an icosahedral protein coat and a singlestranded positive. Pdf virus infection as a function of the host cell life.
Virus is typically shed in the pharynx for 1 to 3 weeks and in the gut for 4 to 8 weeks after primary infection. It is initiated by attachment of the poliovirion to the nterminal vtype immunoglobulinlike domain of its cell surface receptor, the human pv receptor hpvr or cd155 99, 122, 175. The life cycle of all entero v iruses figure 1 starts wit h binding to one or multiple cell surf ace receptors. Many of these individuals will not go on to experience damage to motor nerve cells in the spinal cord and brain stem. Poliovirus is transmitted primarily by the fecaloral route and replicates in the pharynx and lower intestinal tract table 235. Hela cells preincubated in cholinefree medium for 72h were infected with poliovirus and were incubated after infection either in choline. From these experiments, virologists have determined that there is a general pattern observed during the life cycle of a virus that distinguishes it from the life cycle of a bacterium. Poliovirus is a member of the enterovirus subgroup, family picornaviridae. The life cycle of pv occurs within the confines of the cytoplasm of infected cells fig. Looks like they have embedded this as a flash activity.
Depending on the type of nucleic acid, cellular components are used to replicate the viral genome and synthesize viral. Poliomyelitis is a highly contagious infectious disease which has three strains, poliovirus 1 pv1, pv2 and pv3. The complete sequence of poliovirus genomic rna was reported in 1981 by two different groups 19,20. Figure 4 pentamer of the poliovirus capsid showing vp1 blue, vp2 yellow, vp3 red and vp4 green. However, following introduction of effective vaccines, polio incidence declined rapidly. The genus enterovirus ev of the family picornaviridae includes poliovirus, coxsackieviruses, echoviruses, numbered enteroviruses and rhinoviruses. A picornavirus is a virus belonging to the family picornaviridae. This game is part of the online exhibition, whatever happened to polio. Life cycle of polio virus poliovirus, the causative agent of poliomyelitis, is a human enterovirus and member of the family of picornaviridae. Poliovirus is a member of the picornaviridae virus family characterized by. Pdf the life cycle of nonpolio enteroviruses and how to. Immunology and vaccinepreventable diseases pink book polio. Polio, short for poliomyelitis, or infantile paralysis, is an infectious disease caused by the poliovirus.
There are three poliovirus serotypes p1, p2, and p3. Immunology and vaccinepreventable diseases pink book. The last case of wildvirus polio acquired in the united states was in 1979, and global polio eradication may be achieved within this decade. The early years in 1949, john enders, thomas weller, and frederick robbins performed a landmark study showing that poliovirus could be propagated in cultured, nonneural human cells that did not correspond to the tissues infected.
Picornaviruses are small, ether insensitive viruses with an rna genome. The growth cycle of poliovirus in cultured cells fry. Feb 27, 2015 poliovirus is composed of an rna genome and a protein capsid. Poliovirus infection page 1 poliovirus infection 1. Polio virus is rapid, acidresistant, stable, highly tissue specific and consists of a singlestranded, positive rna. Poliovirus receptor molecule is an integral membrane protein consisting of one variable and two constant domains and this receptor molecule attaches to the host cell to initiate replication process. Poliovirus, the causative agent of polio also known as poliomyelitis, is a serotype of the. The first cleavages in cis by 2apro and 3cpro produce the p1, p2 and p3 precursors. Basic concepts replication cycle producesfunctional rnas and proteinsgenomic rna or dna and structural proteins 100s1,000s new particles produced by each cyclereferred to as burst sizemany are defectiveend of eclipse phase replication may be cytolytic or noncytolytic steps in viral replication.
P3 major cleavage produces 3ab and 3cd, minor cleavage 3a, vpg, 3c and 3dpol. The hpv 16 l1 protein selfassembles into vlps that will be released from the infected cell. Poliovirus is a small, nonenveloped icosahedral virus of about 30 nm in diameter fig. To complete the life cycle of the virus, viral proteins are involved in viral replication and translation, in addition to altering host functions, such as cellular gene expression, protein localization, signal transduction and membrane rearrangement.
In tissue culture, poliovirus enters cells and replicates in six to eight hours, yielding 10,000 to 100,000 virus particles per cell. Oct 05, 2017 life cycle of polio virus poliovirus, the causative agent of poliomyelitis, is a human enterovirus and member of the family of picornaviridae. The viral genomic rna itself is utilized as mrna for translation upon entry. The poliovirus genome is translated from a single orf into a large polyprotein. In 1988, the world health organization who passed a resolution to eradicate polio by the year 2000, and the global polio eradication initiative. The basic biology and transmission of poliomyelitis. Poliovirus capsid enters the cell via receptormediated endocytosis.
Dalakas mc, bartfeld h, kurland lt eds the postpolio syndrome, vol 753. Enteroviruses are transient inhabitants of the gastrointestinal tract, and are stable at acid ph. Viral and host proteins involved in picornavirus life cycle. Poliovirus rna was shown to be more than 7,400 nucleotides long, polyadenylated at the 3 terminus, and composed of an open reading frame orf of 2,207 consecutive triplets, spanning over 89% of the total nucleotide sequence. Poliovirus is composed of a rna genome and a protein capsid. The life cycle of poliovirus on a cellular level 10 video on polio transmission video length. This activity will help students understand how polio affected the lives of americans throughout the 20th century. Nov 28, 2019 the life cycle begins with the penetration of the virus into the host cell. A 21st century perspective of poliovirus replication. Structural studies of the coronavirus life cycle robert.
The life cycle of nonpolio enteroviruses and how to. The life cycle of nonpolio enteroviruses and how to target. Studies towards the potential of poliovirus as a vector for the expression of hpv 16 viruslikeparticles. The weakness most often involves the legs, but may less commonly involve the muscles of the head. For more information, log on to download the study materials here this. Poliovirus, pathogenesis of poliomyelitis, and apoptosis. Studies towards the potential of poliovirus as a vector. The cellular life cycle of poliovirus the life cycle of pv occurs within the confines of the cytoplasm of infected cells fig.
Pdf expanding knowledge of p3 proteins in the poliovirus. Life cycle of the poliovirus animation release of virus into blood stream view animation the animation accompanies the exhibition, whatever happened to poliothis animation is intended to give background information on the infectious nature of the disease and how it affects the body. Polio reached a peak in the united states in 1952, with more than 21,000 paralytic cases. A 21st century perspective of poliovirus replication ncbi. Life cycle of the poliovirus animation smithsonians. The virus is composed of a singlestranded, positivesense rna genome and a protein capsid. Leonmonzon me, dalakas mc 1995 detection of poliovirus antibodies and poliovirus genome in patients with postpolio syndrome pps. Type 1 is most often the etiologic agent in paralytic illnesses, type 3 less so and type 2 least commonly. Only small amounts of infectious virus are needed to cause infection. This site explores the history of polio, the science and philanthropy behind the vaccines, the experiences of people who contracted polio and their influence on american culture, and current global efforts at stopping transmission of the poliovirus. The weakness most often involves the legs, but may less commonly involve the muscles of the head, neck and diaphragm.
The infection of cells by enterovirus is an efficient and productive event. Replication cycle of poliovirus, annotated with references to key. The life cycle of the hiv virus is a multistep process. Polio virus is able to reside in the throat or intestinal tract of humans. Arabic pdf file 92 kb pdf logo bosnian pdf file 64 kb pdf logo burmese pdf file 654 kb pdf logo chinese pdf file 182 kb pdf logo dari pdf. People need to be protected against all three types of the virus in order to prevent polio disease and the polio vaccination is the best protection.
There are two vaccines used to protect against polio disease, oral polio vaccine and inactivated poliovirus vaccine. A combination of structural and genetic studies of poliovirus suggests that the final stages of viral assembly lock the virus in a metastable structure primed to undergo the receptorcatalyzed conformational changes required for cell entry. Poliovirus is a member of the picornavirus family, which also includes rhinoviruses, coxsackieviruses, echoviruses, enteroviruses, and hepatitis a virus. Polio, short for poliomyelitis, is an infectious disease caused by the poliovirus. What a nice video from smithsonian museum on how the poliovirus finds a host and starts the disease process. She has written for a wide variety of trade and consumer publications on life sciences topics, particularly in the area of drug discovery and. By viewing the animated lifecycle of the polio virus, students will learn how the poliovirus begins the infection process. Poliovirus type 1, poliovirus type 2 and poliovirus type 3 family. Replication cycle of poliovirus, annotated with references to key findings during the past 65 years.