HaloTag® Platform: From Proteomics to Cellular Analysis and Animal Imaging

From in vitro proteomic protein analysis to in vivo animal models, various protein tagging systems are designed to provide useful functionalities.Commonly used affinity tags for protein purification and capture include GST, c-myc, metal ion affinity tag His6Tag, immuno-affinity FLAG tag, and maltose binding protein (MBP) tag [1][2][3][4].For cellular imaging analysis, fluorescent proteins have served as markers for protein localization, translocation, interactions, and conformational change [5,6].However, in addition to the limited functionality, these protein fusion tags are further limited in that they cannot be used for in vivo animal models.Instead, bioluminescence, near-infrared (NIR) /IR800, Magnetic Resonance Imaging (MRI), positron emission tomography (PET), and single-photon emission tomography (SPECT) are used to detect protein markers in vivo [7,8].Due to limited capabilities for individual tags, studies involving multiple analytical methods often require the use of more than one tag and multiple genetic constructions.