SARS-CoV-2 spike receptor-binding domain (RBD)

The SARS-CoV-2 spike receptor-binding domain (RBD) is a distinct structural region of the viral spike (S) glycoprotein, responsible for recognizing and binding to the host cell receptor angiotensin-converting enzyme 2 (ACE2)[2][3][4][5]. Structurally, the RBD comprises two subdomains: a core and the receptor-binding motif (RBM), which directly contacts ACE2, forming a complex network of polar and hydrophobic interactions essential for viral attachment and entry into cells[2][4]. This domain is the principal target for neutralizing antibodies, vaccines, and entry inhibitors, making it the focal point for both diagnostics and therapeutic development. Mutations within the RBD can significantly affect viral binding affinity to ACE2, impact transmission rates, and enable immune evasion, contributing to the emergence of variants of concern such as those with N501Y, K417N, and E484K substitutions[4][7]. The RBD's high mutation rate presents therapeutic challenges, as changes can reduce the efficacy of monoclonal antibodies and vaccines targeting it. Monitoring antibody levels against the RBD is also a key biomarker for evaluating immune protection and vaccine efficacy[8]. Overall, the SARS-CoV-2 spike receptor-binding domain is a central viral determinant for infection, host range, and immune response modulation.

Other names

Receptor-binding domain of SARS-CoV-2 spike proteinSARS-CoV-2 RBDSpike-RBD

Antibodies neutralize virus by binding RBD and blocking ACE2 interaction; Small-molecule inhibitors interfere with RBD-ACE2 binding to inhibit viral entry[7]; Vaccines elicit immune response against RBD to prevent infection[8]