Nucleotide-binding domain (NBD) (NBD)

The Nucleotide-binding domain (NBD) is a highly conserved structural motif found in a wide variety of proteins, most notably the ATP-binding cassette (ABC) transporters and the Nucleotide-binding oligomerization domain-like receptor (NLR) family. In ABC transporters, the NBD is responsible for binding and hydrolyzing ATP to provide the energy required for the active transport of substrates across cell membranes, a process often implicated in cancer multidrug resistance. In NLR proteins, such as NLRP3, the NBD (specifically the NACHT domain) facilitates ATP-dependent self-oligomerization, which is a critical step in the assembly of the inflammasome and the subsequent release of pro-inflammatory cytokines like IL-1β. Because of its central role in both metabolic transport and innate immunity, the NBD has become a major focus for the development of small-molecule inhibitors and modulators. For example, drugs like MCC950 and Tranilast target the NBD of NLRP3 to treat inflammatory diseases, while CFTR correctors like Lumacaftor target the NBD1 domain to treat cystic fibrosis. However, the high degree of structural similarity between NBDs in different protein families poses a significant challenge for achieving drug selectivity and avoiding off-target toxicity.

Other names

ATP-binding cassetteNACHT domainP-loop NTPase domainABC transporter nucleotide-binding domainNucleotide-binding oligomerization domain

Competitive inhibition of ATP binding, allosteric inhibition of ATP hydrolysis, prevention of ATP-dependent protein oligomerization, and stabilization of domain folding to correct protein trafficking.