SARS-CoV-2 (2019-nCoV) Spike Neutralizing

S

Spike glycoprotein

Spike glycoprotein:
Homotrimer; each monomer consists of a S1 and a S2 subunit (PubMed:32155444, PubMed:32075877). The resulting peplomers protrude from the virus surface as spikes (By similarity).
Interacts with the accessory proteins 3a and 7a.
Spike protein S1:
Binds to human ACE2.

Virion membrane ; Single-pass type I membrane protein ; Host endoplasmic reticulum-Golgi intermediate compartment membrane ; Single-pass type I membrane protein ; Host cell membrane ; Single-pass type I membrane protein ;
Note: Accumulates in the endoplasmic reticulum-Golgi intermediate compartment, where it participates in virus particle assembly. Colocalizes with S in the host endoplasmic reticulum-Golgi intermediate compartment. Some S oligomers are transported to the host plasma membrane, where they may mediate cell-cell fusion.

The cytoplasmic Cys-rich domain is palmitoylated. Spike glycoprotein is digested within host endosomes.
Specific enzymatic cleavages in vivo yield mature proteins. The precurssor is processed into S1 and S2 by host cell furin or another cellular protease to yield the mature S1 and S2 proteins (PubMed:32155444). Additionally, a second cleavage leads to the release of a fusion peptide after viral attachment to host cell receptor (By similarity). The presence of a furin polybasic cleavage site sets SARS-CoV-2 S apart from SARS-CoV S that possesses a monobasic S1/S2 cleavage site processed upon entry of target cells (PubMed:32155444).
Highly decorated by heterogeneous N-linked glycans protruding from the trimer surface.

The cytoplasmic Cys-rich domain is palmitoylated. Spike glycoprotein is digested within host endosomes.
Specific enzymatic cleavages in vivo yield mature proteins. The precurssor is processed into S1 and S2 by host cell furin or another cellular protease to yield the mature S1 and S2 proteins (PubMed:32155444). Additionally, a second cleavage leads to the release of a fusion peptide after viral attachment to host cell receptor (By similarity). The presence of a furin polybasic cleavage site sets SARS-CoV-2 S apart from SARS-CoV S that possesses a monobasic S1/S2 cleavage site processed upon entry of target cells (PubMed:32155444).
Highly decorated by heterogeneous N-linked glycans protruding from the trimer surface.

attaches the virion to the cell membrane by interacting with host receptor, initiating the infection (By similarity). Binding to human ACE2 receptor and internalization of the virus into the endosomes of the host cell induces conformational changes in the Spike glycoprotein (PubMed:32142651, PubMed:32075877, PubMed:32155444). Uses also human TMPRSS2 for priming in human lung cells which is an essential step for viral entry (PubMed:32142651). Proteolysis by cathepsin CTSL may unmask the fusion peptide of S2 and activate membranes fusion within endosomes.