SARS-CoV-2 Spike glycoprotein (S protein) (S protein)

The SARS-CoV-2 Spike (S) glycoprotein is a large, homotrimeric class I fusion protein that decorates the surface of the SARS-CoV-2 virus, mediating viral entry into host cells (UniProt P0DTC2) [1]. It consists of two functional subunits: S1, which contains the receptor-binding domain (RBD), and S2, which facilitates the fusion of the viral and host cell membranes (NCBI) [2]. The RBD specifically targets and binds to the human angiotensin-converting enzyme 2 (ACE2) receptor, a process that is essential for the virus to infect respiratory and other tissues (PubMed) [3]. As the primary surface-exposed protein, it is the main target for neutralizing antibodies produced during natural infection or following vaccination (NIH) [4]. Therapeutic monoclonal antibodies, such as Sotrovimab and Bebtelovimab, are designed to bind to the RBD or other epitopes on the Spike protein to block its interaction with ACE2, thereby preventing viral entry (FDA) [5]. However, the Spike protein is subject to significant antigenic drift, with mutations in the RBD frequently leading to the emergence of variants of concern that can evade immune detection and reduce the efficacy of existing treatments (Nature) [6].

Other names

Spike proteinSurface glycoproteinReceptor-binding domainRBDS1 subunitS2 subunitSARS-CoV-2 Spike RBD

Neutralization of viral entry by blocking the interaction between the viral receptor-binding domain (RBD) and the host angiotensin-converting enzyme 2 (ACE2) receptor (PubMed) [3].