UniProt functional annotation for P03420



	UniProt functional annotation for P03420

UniProt code: P03420.

Organism: Human respiratory syncytial virus A (strain A2).

Taxonomy: Viruses; Riboviria; Orthornavirae; Negarnaviricota; Haploviricotina; Monjiviricetes; Mononegavirales; Pneumoviridae; Orthopneumovirus.

Function: [Fusion glycoprotein F0]: Inactive precursor that is cleaved at two sites by a furin-like protease to give rise to the mature F1 and F2 fusion glycoproteins. {ECO:0000269|PubMed:23593008}.

Function: [Fusion glycoprotein F1]: Class I viral fusion protein (PubMed:23618766). 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 (PubMed:23618766). During viral and plasma cell membrane fusion, the coiled coil regions assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain (PubMed:23618766, PubMed:19966279). The formation of this structure appears to drive apposition and subsequent fusion of viral and cellular membranes leading to delivery of the nucleocapsid into the cytoplasm (PubMed:23593008, PubMed:23618766). This fusion is pH independent and occurs at the plasma or endosomal membrane (Probable). The trimer of F1-F2 (F protein) also facilitates the attachment to host cell by binding to host heparan sulfate (PubMed:10864656). F protein is involved in the entry into the host cell through the interaction with host IGFR1 (PubMed:32494007). This interaction activates PRKCZ/PKCzeta that recruits host NCL/nucleolin to the apical cell surface where it can bind fusion glycoprotein F1 (PubMed:32494007, PubMed:21841784). Later in infection, F protein expressed at the plasma membrane of infected cells can mediate fusion with adjacent cells to form syncytia, a cytopathic effect that could lead to tissue necrosis (PubMed:10438814). F protein may trigger p53-dependent apoptosis (PubMed:18216092). {ECO:0000269|PubMed:10438814, ECO:0000269|PubMed:10864656, ECO:0000269|PubMed:18216092, ECO:0000269|PubMed:19966279, ECO:0000269|PubMed:21841784, ECO:0000269|PubMed:23593008, ECO:0000269|PubMed:23618766, ECO:0000269|PubMed:32494007, ECO:0000305|PubMed:23593008, ECO:0000305|PubMed:30723301}.

Function: [Fusion glycoprotein F2]: Major determinant of the species specificity of RSV infection (PubMed:12663767). The trimer of F1-F2 (F protein) also facilitates the attachment to host cell by binding to host heparan sulfate (PubMed:10864656). F protein is involved in the entry into the host cell through the interaction with host IGFR1 (PubMed:32494007). This interaction activates PRKCZ/PKCzeta that recruits host NCL/nucleolin to the apical cell surface where it can bind fusion glycoprotein F1 (PubMed:32494007). Later in infection, F protein expressed at the plasma membrane of infected cells can mediate fusion with adjacent cells to form syncytia, a cytopathic effect that could lead to tissue necrosis (PubMed:10438814). F protein seems to trigger p53-dependent apoptosis (PubMed:18216092). {ECO:0000269|PubMed:10438814, ECO:0000269|PubMed:10864656, ECO:0000269|PubMed:12663767, ECO:0000269|PubMed:18216092, ECO:0000269|PubMed:32494007}.

Subunit: [Fusion glycoprotein F1]: Homotrimer (PubMed:23618766, PubMed:26333350). Heterodimer with fusion protein F2; disulfide-linked (PubMed:16723026, PubMed:21613394). Interacts with host NCL; this interaction plays a role in viral entry into the host cell (PubMed:21841784). As a heterodimer with F2, interacts with host heparan sulfate (PubMed:10864656). As a heterodimer with F2, interacts with host IGFR1; this interaction activates PRKCZ/PKCzeta that recruits NCL/nucleolin from the host nucleus to the plasma membrane (PubMed:32494007). Part of a complex composed of F1, F2 and G glycoproteins (PubMed:18036342). As a heterodimer with F2, interacts with host RHOA; this interaction facilitates virus-induced syncytium formation (PubMed:10438814). {ECO:0000269|PubMed:10438814, ECO:0000269|PubMed:10864656, ECO:0000269|PubMed:16723026, ECO:0000269|PubMed:18036342, ECO:0000269|PubMed:21613394, ECO:0000269|PubMed:21841784, ECO:0000269|PubMed:23618766, ECO:0000269|PubMed:26333350, ECO:0000269|PubMed:32494007}.

Subunit: [Fusion glycoprotein F2]: Homotrimer (PubMed:26333350, PubMed:23618766). Heterodimer with fusion protein F1; disulfide-linked (PubMed:26333350, PubMed:16723026, PubMed:21613394). As a heterodimer with F1, interacts with host heparan sulfate (PubMed:10864656). As a heterodimer with F1, interacts with host IGFR1; this interaction activates PRKCZ/PKCzeta that recruits NCL/nucleolin from the host nucleus to the plasma membrane (PubMed:32494007). Part of a complex composed of F1, F2 and G glycoproteins (PubMed:18036342). As a heterodimer with F1, interacts with host RHOA; this interaction facilitates virus-induced syncytium formation (PubMed:10438814). {ECO:0000269|PubMed:10438814, ECO:0000269|PubMed:10864656, ECO:0000269|PubMed:16723026, ECO:0000269|PubMed:18036342, ECO:0000269|PubMed:21613394, ECO:0000269|PubMed:23618766, ECO:0000269|PubMed:26333350, ECO:0000269|PubMed:32494007}.

Subcellular location: [Fusion glycoprotein F0]: Host Golgi apparatus membrane {ECO:0000305|PubMed:16160180}; Single-pass membrane protein {ECO:0000269|PubMed:16160180}.

Subcellular location: [Fusion glycoprotein F1]: Virion membrane {ECO:0000269|PubMed:23776214}; Single-pass type I membrane protein {ECO:0000269|PubMed:16160180}. Host cell membrane {ECO:0000269|PubMed:16160180}; Single-pass membrane protein {ECO:0000269|PubMed:16160180}. Note=Localized at the host apical membrane. {ECO:0000269|PubMed:16160180}.

Subcellular location: [Fusion glycoprotein F2]: Virion membrane {ECO:0000269|PubMed:23776214}. Host cell membrane {ECO:0000305}. Note=Localized at the host apical membrane. {ECO:0000305}.

Domain: [Fusion glycoprotein F0]: The N-terminus is a hydrophobic fusion peptide that inserts into the target host membrane (By similarity). It is buried in the center of the trimer cavity before cleavage by host furin (PubMed:23618766). The coiled coil (heptad repeat) regions are probably involved in homotrimerization, heterodimerization and in the formation of a fusion-active hairpin structure (PubMed:10846072, PubMed:29212939). {ECO:0000250|UniProtKB:P11209, ECO:0000269|PubMed:10846072, ECO:0000269|PubMed:23618766, ECO:0000269|PubMed:29212939}.

Domain: [Fusion glycoprotein F1]: The N-terminus is a hydrophobic fusion peptide that inserts into the target host membrane (By similarity). It is buried in the center of the trimer cavity before cleavage by host furin (PubMed:23618766). The coiled coil (heptad repeat) regions are probably involved in homotrimerization, heterodimerization and in the formation of a fusion-active hairpin structure (PubMed:10846072). {ECO:0000250|UniProtKB:P11209, ECO:0000269|PubMed:10846072, ECO:0000269|PubMed:23618766}.

Ptm: [Fusion glycoprotein F0]: The F glycoprotein is synthesized as a F0 inactive precursor that is heavily N-glycosylated and processed at two sites by a host furin-like protease probably in the Golgi (PubMed:11493675, PubMed:11369882, PubMed:23593008, PubMed:11418598). The cleavage site between p27 and F1 may occur after endocytosis to yield the mature F1 and F2 proteins (Probable). Both cleavages are required for membrane fusion and p27 is released from the processed protein (PubMed:11493675, PubMed:23593008, PubMed:12127793). {ECO:0000269|PubMed:11369882, ECO:0000269|PubMed:11418598, ECO:0000269|PubMed:11493675, ECO:0000269|PubMed:12127793, ECO:0000269|PubMed:23593008, ECO:0000305|PubMed:23593008}.

Similarity: Belongs to the paramyxoviruses fusion glycoprotein family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Human respiratory syncytial virus A (strain A2).
Taxonomy:		Viruses; Riboviria; Orthornavirae; Negarnaviricota; Haploviricotina; Monjiviricetes; Mononegavirales; Pneumoviridae; Orthopneumovirus.



Function:		[Fusion glycoprotein F0]: Inactive precursor that is cleaved at two sites by a furin-like protease to give rise to the mature F1 and F2 fusion glycoproteins. {ECO:0000269\|PubMed:23593008}.



Function:		[Fusion glycoprotein F1]: Class I viral fusion protein (PubMed:23618766). 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 (PubMed:23618766). During viral and plasma cell membrane fusion, the coiled coil regions assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain (PubMed:23618766, PubMed:19966279). The formation of this structure appears to drive apposition and subsequent fusion of viral and cellular membranes leading to delivery of the nucleocapsid into the cytoplasm (PubMed:23593008, PubMed:23618766). This fusion is pH independent and occurs at the plasma or endosomal membrane (Probable). The trimer of F1-F2 (F protein) also facilitates the attachment to host cell by binding to host heparan sulfate (PubMed:10864656). F protein is involved in the entry into the host cell through the interaction with host IGFR1 (PubMed:32494007). This interaction activates PRKCZ/PKCzeta that recruits host NCL/nucleolin to the apical cell surface where it can bind fusion glycoprotein F1 (PubMed:32494007, PubMed:21841784). Later in infection, F protein expressed at the plasma membrane of infected cells can mediate fusion with adjacent cells to form syncytia, a cytopathic effect that could lead to tissue necrosis (PubMed:10438814). F protein may trigger p53-dependent apoptosis (PubMed:18216092). {ECO:0000269\|PubMed:10438814, ECO:0000269\|PubMed:10864656, ECO:0000269\|PubMed:18216092, ECO:0000269\|PubMed:19966279, ECO:0000269\|PubMed:21841784, ECO:0000269\|PubMed:23593008, ECO:0000269\|PubMed:23618766, ECO:0000269\|PubMed:32494007, ECO:0000305\|PubMed:23593008, ECO:0000305\|PubMed:30723301}.



Function:		[Fusion glycoprotein F2]: Major determinant of the species specificity of RSV infection (PubMed:12663767). The trimer of F1-F2 (F protein) also facilitates the attachment to host cell by binding to host heparan sulfate (PubMed:10864656). F protein is involved in the entry into the host cell through the interaction with host IGFR1 (PubMed:32494007). This interaction activates PRKCZ/PKCzeta that recruits host NCL/nucleolin to the apical cell surface where it can bind fusion glycoprotein F1 (PubMed:32494007). Later in infection, F protein expressed at the plasma membrane of infected cells can mediate fusion with adjacent cells to form syncytia, a cytopathic effect that could lead to tissue necrosis (PubMed:10438814). F protein seems to trigger p53-dependent apoptosis (PubMed:18216092). {ECO:0000269\|PubMed:10438814, ECO:0000269\|PubMed:10864656, ECO:0000269\|PubMed:12663767, ECO:0000269\|PubMed:18216092, ECO:0000269\|PubMed:32494007}.


Subunit:		[Fusion glycoprotein F1]: Homotrimer (PubMed:23618766, PubMed:26333350). Heterodimer with fusion protein F2; disulfide-linked (PubMed:16723026, PubMed:21613394). Interacts with host NCL; this interaction plays a role in viral entry into the host cell (PubMed:21841784). As a heterodimer with F2, interacts with host heparan sulfate (PubMed:10864656). As a heterodimer with F2, interacts with host IGFR1; this interaction activates PRKCZ/PKCzeta that recruits NCL/nucleolin from the host nucleus to the plasma membrane (PubMed:32494007). Part of a complex composed of F1, F2 and G glycoproteins (PubMed:18036342). As a heterodimer with F2, interacts with host RHOA; this interaction facilitates virus-induced syncytium formation (PubMed:10438814). {ECO:0000269\|PubMed:10438814, ECO:0000269\|PubMed:10864656, ECO:0000269\|PubMed:16723026, ECO:0000269\|PubMed:18036342, ECO:0000269\|PubMed:21613394, ECO:0000269\|PubMed:21841784, ECO:0000269\|PubMed:23618766, ECO:0000269\|PubMed:26333350, ECO:0000269\|PubMed:32494007}.
Subunit:		[Fusion glycoprotein F2]: Homotrimer (PubMed:26333350, PubMed:23618766). Heterodimer with fusion protein F1; disulfide-linked (PubMed:26333350, PubMed:16723026, PubMed:21613394). As a heterodimer with F1, interacts with host heparan sulfate (PubMed:10864656). As a heterodimer with F1, interacts with host IGFR1; this interaction activates PRKCZ/PKCzeta that recruits NCL/nucleolin from the host nucleus to the plasma membrane (PubMed:32494007). Part of a complex composed of F1, F2 and G glycoproteins (PubMed:18036342). As a heterodimer with F1, interacts with host RHOA; this interaction facilitates virus-induced syncytium formation (PubMed:10438814). {ECO:0000269\|PubMed:10438814, ECO:0000269\|PubMed:10864656, ECO:0000269\|PubMed:16723026, ECO:0000269\|PubMed:18036342, ECO:0000269\|PubMed:21613394, ECO:0000269\|PubMed:23618766, ECO:0000269\|PubMed:26333350, ECO:0000269\|PubMed:32494007}.
Subcellular location:		[Fusion glycoprotein F0]: Host Golgi apparatus membrane {ECO:0000305\|PubMed:16160180}; Single-pass membrane protein {ECO:0000269\|PubMed:16160180}.
Subcellular location:		[Fusion glycoprotein F1]: Virion membrane {ECO:0000269\|PubMed:23776214}; Single-pass type I membrane protein {ECO:0000269\|PubMed:16160180}. Host cell membrane {ECO:0000269\|PubMed:16160180}; Single-pass membrane protein {ECO:0000269\|PubMed:16160180}. Note=Localized at the host apical membrane. {ECO:0000269\|PubMed:16160180}.
Subcellular location:		[Fusion glycoprotein F2]: Virion membrane {ECO:0000269\|PubMed:23776214}. Host cell membrane {ECO:0000305}. Note=Localized at the host apical membrane. {ECO:0000305}.
Domain:		[Fusion glycoprotein F0]: The N-terminus is a hydrophobic fusion peptide that inserts into the target host membrane (By similarity). It is buried in the center of the trimer cavity before cleavage by host furin (PubMed:23618766). The coiled coil (heptad repeat) regions are probably involved in homotrimerization, heterodimerization and in the formation of a fusion-active hairpin structure (PubMed:10846072, PubMed:29212939). {ECO:0000250\|UniProtKB:P11209, ECO:0000269\|PubMed:10846072, ECO:0000269\|PubMed:23618766, ECO:0000269\|PubMed:29212939}.
Domain:		[Fusion glycoprotein F1]: The N-terminus is a hydrophobic fusion peptide that inserts into the target host membrane (By similarity). It is buried in the center of the trimer cavity before cleavage by host furin (PubMed:23618766). The coiled coil (heptad repeat) regions are probably involved in homotrimerization, heterodimerization and in the formation of a fusion-active hairpin structure (PubMed:10846072). {ECO:0000250\|UniProtKB:P11209, ECO:0000269\|PubMed:10846072, ECO:0000269\|PubMed:23618766}.
Ptm:		[Fusion glycoprotein F0]: The F glycoprotein is synthesized as a F0 inactive precursor that is heavily N-glycosylated and processed at two sites by a host furin-like protease probably in the Golgi (PubMed:11493675, PubMed:11369882, PubMed:23593008, PubMed:11418598). The cleavage site between p27 and F1 may occur after endocytosis to yield the mature F1 and F2 proteins (Probable). Both cleavages are required for membrane fusion and p27 is released from the processed protein (PubMed:11493675, PubMed:23593008, PubMed:12127793). {ECO:0000269\|PubMed:11369882, ECO:0000269\|PubMed:11418598, ECO:0000269\|PubMed:11493675, ECO:0000269\|PubMed:12127793, ECO:0000269\|PubMed:23593008, ECO:0000305\|PubMed:23593008}.
Similarity:		Belongs to the paramyxoviruses fusion glycoprotein family. {ECO:0000305}.