Native Parainfluenza Virus type 2 protein

Supplementary info

This supplementary information is collated from multiple sources and compiled automatically.

Activity summary

Parainfluenza virus type 2 (PIV-2) is an enveloped negative-sense single-stranded RNA virus. It belongs to the Paramyxoviridae family and specifically targets respiratory epithelial cells. The genome of PIV-2 encodes six structural proteins and two nonstructural proteins with hemagglutinin-neuraminidase (HN) and fusion (F) proteins playing key roles in viral entry and spread. The virus has a genome of approximately 15000 nucleotides. Its structural proteins are synthesized in host cell cytoplasm and incorporated into new virions at the cell surface.

Biological function summary

PIV-2 causes respiratory tract infections. It primarily infects children and can lead to conditions like croup bronchiolitis and pneumonia. The virus's HN and F proteins facilitate attachment to host cells and membrane fusion respectively enabling viral entry. The nonstructural proteins modulate the host immune response enhancing the virus's ability to replicate and persist. PIV-2 does not form a traditional molecular complex but interacts with host cell surface receptors to initiate infection.

Pathways

PIV-2 exploits the cell's endocytotic pathway to gain entry. The HN protein binds sialic acid residues on host cell surfaces an initial step in the infection pathway. Following attachment the F protein mediates fusion between the viral envelope and host cell membrane critical for genomic release into the host cytoplasm. PIV-2 shares pathway relationships with other paramyxoviruses such as respiratory syncytial virus (RSV) due to similar infection mechanisms involving cell surface protein interactions.

Associated diseases and disorders

PIV-2 significantly impacts pediatric respiratory health. It frequently causes croup in young children characterized by a distinctive 'barking' cough and stridor. Severe cases can lead to pneumonia necessitating medical intervention. The F protein's role in triggering host cell syncytia formation contributes to disease pathology and shares functional characteristics with similar proteins in other respiratory viruses including measles virus. Recognizing PIV-2's role in these conditions is important for effective management and therapeutic strategies.