Receptor-binding domain of spike glycoprotein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 RBD)

The receptor-binding domain (RBD) is a critical component of the S1 subunit of the SARS-CoV-2 spike glycoprotein, responsible for mediating the virus's entry into host cells [1]. It specifically recognizes and binds to the human Angiotensin-converting enzyme 2 (ACE2) receptor with high affinity, a process that triggers the subsequent fusion of the viral and host cell membranes [2][3]. Because of its essential role in the infection cycle, the RBD is the primary target for the host's neutralizing antibody response and the focus of most therapeutic monoclonal antibodies and vaccine designs [2]. Therapeutic agents targeting the RBD, such as bebtelovimab or sotrovimab, aim to block the RBD-ACE2 interface, effectively neutralizing the virus's ability to infect cells [4]. However, the RBD is also a hotspot for mutations, leading to the emergence of variants of concern that can evade existing treatments and vaccines [3]. Understanding the structural and functional dynamics of the RBD remains vital for developing broad-spectrum countermeasures against evolving coronaviruses [2].

Other names

SARS-CoV-2 S-RBD [1]Spike protein RBD [2]S1-RBD [1]RBD of SARS-CoV-2 spike protein [3]

Neutralizing antibodies bind to the RBD, sterically hindering its interaction with the host Angiotensin-converting enzyme 2 (ACE2) receptor, thereby preventing viral attachment and entry into host cells [2][3].