All Topics  
Paramyxovirus

 

 
   Email Print
   Bookmark   Link
 

 

Paramyxovirus
 
 
  Topics Paramyxovirus Topic Home

Paramyxoviruses are virus
Virus

A virus is a Optical microscope#Limitations of light microscopes infectious agent that is unable to grow or reproduce outside a host cell . Viruses infect all cellular life....
es of the Paramyxoviridae family of the Mononegavirales
Mononegavirales

The Mononegavirales are an order of viruses comprising species that have a non-segmented, Sense RNA genome. The order includes four families:...
 order; they are negative-sense single-stranded RNA
RNA

Ribonucleic acid is a type of molecule that consists of a long chain of nucleotide units. Each nucleotide consists of a nucleobase, a ribose sugar, and a phosphate....
 viruses responsible for a number of human and animal disease
Disease

A disease or medical condition is an abnormal condition of an organism that impairs bodily functions, associated with specific symptoms and Medical signs....
s.


ons are enveloped and can be spherical, filamentous or pleomorphic. Fusion proteins and attachment proteins appear as spikes on the virion surface.






Discussion
Ask a question about 'Paramyxovirus'
Start a new discussion about 'Paramyxovirus'
Answer questions from other users
Full Discussion Forum



Encyclopedia


Paramyxoviruses are virus
Virus

A virus is a Optical microscope#Limitations of light microscopes infectious agent that is unable to grow or reproduce outside a host cell . Viruses infect all cellular life....
es of the Paramyxoviridae family of the Mononegavirales
Mononegavirales

The Mononegavirales are an order of viruses comprising species that have a non-segmented, Sense RNA genome. The order includes four families:...
 order; they are negative-sense single-stranded RNA
RNA

Ribonucleic acid is a type of molecule that consists of a long chain of nucleotide units. Each nucleotide consists of a nucleobase, a ribose sugar, and a phosphate....
 viruses responsible for a number of human and animal disease
Disease

A disease or medical condition is an abnormal condition of an organism that impairs bodily functions, associated with specific symptoms and Medical signs....
s.

Genera

  • Subfamily Paramyxovirinae
    • Genus Avulavirus
      Avulavirus

      The genus Avulavirus is one of eight genera in the family Paramyxoviridae and contains viruses that used to be classified in the genus Rubulavirus, but which infect birds and translate protein V from an edited RNA transcript....
       (type species Newcastle disease virus)
    • Genus Henipavirus
      Henipavirus

      Henipavirus is a genus of the Family Paramyxoviridae, Order Mononegavirales containing two members, Hendravirus and Nipahvirus....
       (type species Hendravirus; others include Nipahvirus)
    • Genus Morbillivirus
      Morbillivirus

      Morbillivirus is a genus belonging to the Paramyxoviridae family of viruses in the order Mononegavirales. Many members of the genus cause diseases, such as rinderpest and measles, and are highly infectious....
       (type species Measles virus; others include Rinderpest virus, Canine distemper virus, phocine distemper virus
      Phocine distemper virus

      Phocine distemper virus is a paramyxovirus of the genus morbillivirus that is pathogenic for pinniped species, particularly seals. Clinical signs include laboured breathing, fever and nervous symptoms....
      , Peste des Petits Ruminants virus (PPR))
    • Genus Respirovirus (type species Sendai virus
      Sendai virus

      Sendai virus , also known as murine parainfluenza virus type 1, is a negative sense, single-stranded RNA virus of the Paramyxoviridae family, a group of viruses featuring, notably, the Morbillivirus and Rubulavirus genera....
      ; others include Human parainfluenza viruses
      Human parainfluenza viruses

      Human parainfluenza viruses are a group of four distinct serotypes of single-stranded RNA viruses belonging to the paramyxovirus family. They are the second most common cause of lower respiratory tract infection in younger children....
       1 and 3, as well some of the viruses of the common cold
      Common cold

      Acute viral rhinopharyngitis, or acute coryza, usually known as the common cold, is a highly contagious, virus infectious disease of the upper respiratory system, primarily caused by picornaviruses or coronaviruses....
      )
    • Genus Rubulavirus
      Rubulavirus

      Rubulavirus is a genus of the Paramyxoviridae family of infectious viruses. The genus includes the mumps virus and parainfluenza type 2, 4a and 4b viruses....
       (type species Mumps virus
      Mumps virus

      Mumps virus is the virus that causes the disease mumps.It is a member of the Paramyxoviridae family.An example of a wild type is 88-1961....
      ; others include Simian parainfluenza virus 5, Menangle virus
      Menangle virus

      Menangle virus is a virus that infects pigs, humans and bats....
      , Tioman virus
      Tioman virus

      Tioman virus is a paramyxovirus first isolated from the urine of island fruit bats on Tioman Island, Malaysia in 2000. The virus was discovered during efforts to identify the natural host of Nipah virus which was responsible for a large outbreak of encephalitic illness in humans and pigs in Malaysia and Singapore in 1998-99....
      )
    • Genus TPMV-like viruses (type species Tupaia paramyxovirus)
  • Subfamily Pneumovirinae
    • Genus Pneumovirus (type species Human respiratory syncytial virus
      Human respiratory syncytial virus

      Human respiratory syncytial virus is a negative-sense, single-stranded RNA virus of the family Paramyxoviridae, which includes common respiratory viruses such as those causing measles and mumps....
      , others include Bovine respiratory syncytial virus)
    • Genus Metapneumovirus
      Metapneumovirus

      Human metapneumovirus was isolated for the first time in 2001 in the Netherlands by using the RAP-PCR technique for identification of unknown viruses growing in cultured cells....
       (type species Avian pneumovirus, Human metapneumovirus)
  • Unassigned viruses
    • Fer-de-Lance virus
    • Nariva virus
    • Tupaia paramyxovirus
    • Salem virus
    • J virus
    • Mossman virus
    • Beilong virus


Physical structure

Virions are enveloped and can be spherical, filamentous or pleomorphic. Fusion proteins and attachment proteins appear as spikes on the virion surface. Matrix proteins inside the envelope stabilise virus structure. The nucleocapsid core is composed of the genomic RNA, nucleocapsid proteins, phosphoproteins and polymerase proteins.

Genome structure

The genome
Genome

In classical genetics, the genome of a diploid organism including eukarya refers to a full set of chromosomes or genes in a gamete; thereby, a regular somatic cell contains two full sets of genomes....
 consists of a single segment of negative-sense RNA, 15-19 kilobases in length and containing 6-10 genes. Extracistronic (non-coding) regions include:
  • A 3’ leader sequence, 50 nucleotides in length which acts as a transcription
    Transcription (genetics)

    Transcription is the synthesis of RNA under the direction of DNA. RNA synthesis, or transcription, is the process of transcribing DNA nucleotide sequence information into RNA sequence information....
    al promoter.
  • A 5’ trailer sequence, 50-161 nucleotides long
  • Intergenomic regions between each gene
    Gene

    A gene is the basic unit of heredity in a living organism. All living things depend on genes. Genes hold the information to build and maintain their cell and pass genetic trait to offspring....
     which are three nucleotides long for morbillivirus, respirovirus and henipavirus, variable length (1-56 nucleotides) for rubulavirus and pneumovirinae.


Each gene contains transcription start/stop signals at the beginning and end which are transcribed as part of the gene.

Gene sequence within the genome is conserved across the family due to a phenomenon known as transcriptional polarity (see Mononegavirales
Mononegavirales

The Mononegavirales are an order of viruses comprising species that have a non-segmented, Sense RNA genome. The order includes four families:...
) in which genes closest to the 3’ end of the genome are transcribed in greater abundance than those towards the 5’ end. This mechanism acts as a form of transcriptional regulation.

The gene sequence is:
  • Nucleocapsid – Phosphoprotein – Matrix – Fusion – Attachment – Large (polymerase)


Proteins

  • N – the nucleocapsid protein associates with genomic RNA (one molecule per hexamer) and protects the RNA from nuclease digestion
  • P – the phosphoprotein binds to the N and L proteins and forms part of the RNA polymerase complex
  • M – the matrix protein assembles between the envelope and the nucleocapsid core, it organizes and maintains virion structure
  • F – the fusion protein projects from the envelope surface as a trimer, and mediates cell entry
    Viral entry

    Viral entry is the earliest stage of infection in the viral life cycle, as the virus comes into contact with the host cell and introduces viral material into the cell....
     by inducing fusion between the viral envelope and the cell membrane by class I fusion. One of the defining characteristics of members of the paramyxoviridae family is the requirement for a neutral pH for fusogenic activity.
  • H/HN/G – the cell attachment proteins span the viral envelope and project from the surface as spikes. They bind to sialic acid on the cell surface and facilitate cell entry. Note that the receptor for measles virus is unknown. Proteins are designated H for morbilliviruses and henipaviruses as they possess haemagglutination activity, observed as an ability to cause red blood cells to clump. HN attachment proteins occur in respiroviruses and rubulaviruses. These possess both haemagglutination and neuraminidase activity which cleaves sialic acid on the cell surface, preventing viral particles from reattaching to previously infected cells. Attachment proteins with neither haemagglutination nor neuraminidase activity are designated G (glycoprotein
    Glycoprotein

    Not to be confused with peptidoglycan or proteoglycan.Glycoproteins are proteins that contain oligosaccharide chains covalently attached to their Peptide side-chains....
    ). These occur in members of pneumovirinae.
  • L – the large protein is the catalytic subunit of RNA dependent RNA polymerase (RDRP)
  • Accessory proteins – a mechanism known as RNA editing (see Mononegavirales
    Mononegavirales

    The Mononegavirales are an order of viruses comprising species that have a non-segmented, Sense RNA genome. The order includes four families:...
    ) allows multiple proteins to be produced from the P gene. These are not essential for replication but may aid in survival in vitro or may be involved in regulating the switch from mRNA synthesis to antigenome synthesis.


Pathogenic paramyxoviruses

A number of important human diseases are caused by paramyxoviruses. These include mumps
MUMPS

MUMPS , or alternatively M, is a programming language created in the late 1960s, originally for use in the Health care. It was designed for the production of multi-user database-driven applications....
, measles
Measles

Measles is a infection of the respiratory system caused by a virus, specifically a paramyxovirus of the genus Morbillivirus. Morbilliviruses, like other paramyxoviruses, are enveloped, single-stranded, negative-sense RNA viruses....
, which caused 745,000 deaths in 2001 and respiratory syncytial virus (RSV) which is the major cause of bronchiolitis
Bronchiolitis

Bronchiolitis is inflammation of the bronchioles, the smallest air passages of the lungs. This inflammation is usually caused by viruses. More on this can be found below....
 and pneumonia
Pneumonia

Pneumonia is an Inflammation illness of the lung. Frequently, it is described as lung parenchyma/alveolus inflammation and abnormal alveolar filling with fluid ....
 in infants and children.

The parainfluenza
Human parainfluenza viruses

Human parainfluenza viruses are a group of four distinct serotypes of single-stranded RNA viruses belonging to the paramyxovirus family. They are the second most common cause of lower respiratory tract infection in younger children....
 viruses are the second most common causes of respiratory tract disease in infants and children. They can cause pneumonia, bronchitis
Bronchitis

Bronchitis is an inflammation of the large bronchus in the lungs. It can progress to pneumonia. Acute bronchitis is usually caused by viruses or bacteria and may last several days or weeks....
 and croup
Croup

Croup is a group of respiratory diseases that often affects infants and children under age 6. It is characterized by a barking cough; a whistling, obstructive sound as the child breathes in; and hoarseness due to obstruction in the region of the larynx....
 in children and the elderly.

Human metapneumovirus, initially described in about 2001, is also implicated in bronchitis, especially in children.

Paramyxoviruses are also responsible for a range of diseases in other animal species, for example canine distemper virus (dog
Dog

The dog is a domesticated subspecies of the Gray Wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties....
s), phocine distemper virus
Phocine distemper virus

Phocine distemper virus is a paramyxovirus of the genus morbillivirus that is pathogenic for pinniped species, particularly seals. Clinical signs include laboured breathing, fever and nervous symptoms....
 (seals), cetacean morbillivirus (dolphin
Dolphin

File:Bottlenose_Dolphin_KSC04pd0178.jpgDolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genus....
s and porpoise
Porpoise

Porpoises are small cetaceans of the family Phocoenidae; they are related to whales and dolphins. They are distinct from dolphins, although the word "porpoise" has been used to refer to any small dolphin, especially by sailors and fishermen....
s) Newcastle disease virus (birds) and rinderpest virus (cattle
Cattle

Cattle, colloquially referred to as cows, are domestication ungulates, a member of the subfamily Bovinae of the family Bovidae. They are raised as livestock for meat , dairy products , leather and as draft animals ....
). Some paramyxoviruses such as the henipaviruses are zoonotic
Zoonosis

A zoonosis or zoonose is any infectious disease that is able to be transmitted from other animals, both wild and domestic, to humans or from humans to animals ....
 pathogens, occurring naturally in an animal host, but also able to infect humans.

Hendra virus (HeV) and Nipah virus (NiV) in the genus Henipavirus
Henipavirus

Henipavirus is a genus of the Family Paramyxoviridae, Order Mononegavirales containing two members, Hendravirus and Nipahvirus....
 have emerged in humans and livestock in Australia
Australia

Australia, officially the Commonwealth of Australia, is a country in the southern hemisphere comprising the Australia of the world's smallest continent, the major island of Tasmania, and numerous list of islands of Australia in the Indian Ocean and Pacific Oceans....
 and Southeast Asia
Asia

Asia is the world's largest and most populous continent. It covers 8.6% of the Earth's total surface area and, with over 4 billion people, it contains more than 60% of the world's current human population....
. Both viruses are contagious
Contagious

Contagious may refer to:*Contagious disease*Contagious , a song by the Isley Brothers*Contagious, a 2007 in music song from Avril Lavigne's album "The Best Damn Thing"...
, highly virulent, and capable of infecting a number of mammalian species and causing potentially fatal disease. Due to the lack of a licensed vaccine
Vaccine

A vaccine is a biological preparation that establishes or improves immunity to a particular disease.Vaccines can be prophylaxis , or Medication ....
 or antiviral therapies, HeV and NiV are designated as biosafety level (BSL) 4 agents. The genomic structure of both viruses is that of a typical paramyxovirus.

See also

  • Animal viruses
    Animal virology

    The study of animal viruses is important from a veterinary viewpoint and many of these viruses cause diseases that are economically devastating. Many animal viruses are also important from a human medical perspective....
  • Virology
    Virology

    Virology is the study of virus : their structure, classification and evolution, their ways to infect and exploit cell for virus reproduction, the diseases they cause, the techniques to isolate and culture them, and their use in research and therapy....
  • Henipavirus
    Henipavirus

    Henipavirus is a genus of the Family Paramyxoviridae, Order Mononegavirales containing two members, Hendravirus and Nipahvirus....


External links

  • — morphology, genome, replication, pathogenesis (special access required)
  • CSIRO Paramyxovirus press release
  • Viral Bioinformatics Resource Center