Many enveloped viruses possess a fusion protein in their envelopes. This confers the ability of the virion to fuse with the host cell membrane and thus allow entry of the infectious genomic material into the cell cytoplasm. During replication of the virus, expression of the fusion protein at the cell membrane can result in the fusion of neighbouring cells, and the formation of multi-nucleate cells or syncytia.
Also we know that viral envelope is originated from membrane (cellular, nuclear and etc.)
Fusion protein usually is exposed after interaction with a receptor on cell membrane. This receptors are not present on virus membrane. Some examples: HIV fusion protein, gp41, is exposed when conformational changes on gp120 are induced by interaction with CD4 and CCR5. Influenza fusion protein is part of the hemagglutinin, which suffer conformational changes intra endosomes under low pH.
The Respiratory syncytial virus (a member of paramyxovirus family) has a functional fusion protein in their envelope (is pH-independent), it does not need be exposed to response to conformational changes. I think that the syncytia formation is not possible because the virus often budding in regions of the plasma membrane where the receptor is absent, then the other viruses can`t bind each other. another posibility is that viral envelope has a limited surface, and maybe is very difficult than fusion proteins can interact with molecules in the surface of the other virus.
Hello all is true what they say, but it is much more complex, geminivirus can have one or two genomes, and this makes it is more specific recognition despite being in the same family. I attached a file that despite being the 2002 has many foundations. I hope to serve you
@Charlotte Hársi : thanks for your help.
@ Lisandro Pacheco : Thanks, limited surface of virus is a good point you mentioned.
@ Diana Medina-Hernandez: hello, thanks for your help, appreciate your kindness
- Badges
- Science topic
- Similar topics
- Biological Science
- Microbiology
- Virology