Haloalkane dehalogenase (HaloTag) (HaloTag)

HaloTag is a 34 kDa engineered protein tag derived from the bacterial haloalkane dehalogenase (DhaA) of Rhodococcus rhodochrous. It is designed to covalently and irreversibly bind to synthetic ligands containing a primary chloroalkane linker [Promega Corporation. HaloTag Technology]. This technology is widely utilized in molecular biology for protein visualization, purification, and functional analysis in both live cells and in vitro. In drug discovery, HaloTag is a critical component of the Halo-PROTAC system, where it serves as a handle to recruit specific proteins for proteasomal degradation [Neklesa, T. K., et al. (2011). Nature Chemical Biology, 7(8), 538-543]. While not a natural therapeutic target, its ability to facilitate targeted protein degradation makes it a valuable tool in developing novel therapeutic strategies and studying protein function in disease states. The specificity and stability of the HaloTag-ligand bond allow for high-resolution imaging and precise control over protein levels in experimental models. The system's versatility is enhanced by the availability of various ligands, including fluorescent dyes, biotin, and solid supports, making it a cornerstone of modern chemical biology.

Other names

Halo-tagModified haloalkane dehalogenaseDhaA variantHaloTag7

HaloTag is a modified haloalkane dehalogenase that reacts with synthetic chloroalkane ligands to form a highly stable, covalent ester bond. This reaction is rapid and irreversible under physiological conditions, allowing for the specific labeling of HaloTag-fusion proteins with various functional groups, such as fluorophores or degradation-inducing moieties [Los, G. V., et al. (2008). ACS Chemical Biology, 3(6), 373-382].