Structural highlights
Function
[ENV_RSVSA] The surface protein (SU) attaches the virus to the host cell by binding to its receptor. This interaction triggers the refolding of the transmembrane protein (TM) and is thought to activate its fusogenic potential by unmasking its fusion peptide. Fusion occurs at the host cell plasma membrane (By similarity). The transmembrane protein (TM) acts as a class I viral fusion protein. Under the current model, the protein has at least 3 conformational states: pre-fusion native state, pre-hairpin intermediate state, and post-fusion hairpin state. During viral and target cell membrane fusion, the coiled coil regions (heptad repeats) assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain. The formation of this structure appears to drive apposition and subsequent fusion of viral and target cell membranes. Membranes fusion leads to delivery of the nucleocapsid into the cytoplasm (By similarity).
Publication Abstract from PubMed
The structure and membrane interaction of the internal fusion peptide (IFP) fragment of the avian sarcoma and leucosis virus (ASLV) envelope glycoprotein was studied by an array of biophysical methods. The peptide was found to induce lipid mixing of vesicles more strongly than the fusion peptide derived from the N-terminal fusion peptide of influenza virus (HA2-FP). It was observed that the helical structure was enhanced in association with the model membranes, particularly in the N-terminal portion of the peptide. According to the infrared study, the peptide inserted into the membrane in an oblique orientation, but less deeply than the influenza HA2-FP. Analysis of NMR data in sodium dodecyl sulfate micelle suspension revealed that Pro13 of the peptide was located near the micelle-water interface. A type II beta-turn was deduced from NMR data for the peptide in aqueous medium, demonstrating a conformational flexibility of the IFP in analogy to the N-terminal FP such as that of gp41. A loose and multimodal self-assembly was deduced from the rhodamine fluorescence self-quenching experiments for the peptide bound to the membrane bilayer. Oligomerization of the peptide and its variants can also be observed in the electrophoretic experiments, suggesting a property in common with other N-terminal FP of class I fusion proteins.
Structure and membrane interaction of the internal fusion peptide of avian sarcoma leukosis virus.,Cheng SF, Wu CW, Kantchev EA, Chang DK Eur J Biochem. 2004 Dec;271(23-24):4725-36. PMID:15606759[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Cheng SF, Wu CW, Kantchev EA, Chang DK. Structure and membrane interaction of the internal fusion peptide of avian sarcoma leukosis virus. Eur J Biochem. 2004 Dec;271(23-24):4725-36. PMID:15606759 doi:http://dx.doi.org/EJB4436
