Highly activatable and environment-insensitive optical highlighters for selective spatiotemporal imaging of target proteins.
Optical highlighters are photoactivatable fluorescent molecules that exhibit pronounced changes in their spectral properties in response to irradiation with light of a specific wavelength and intensity. Here, we present a novel design strategy for a new class of caged BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) fluorophores, based on the use of photoremovable protecting groups (PRPGs) with high reduction potentials that serve as both a photosensitive unit and a fluorescence quencher via photoinduced electron transfer (PeT). 2,6-Dinitrobenzyl (DNB)-caged BODIPY was efficiently photoactivated, with activation ratios exceeding 600-fold in aqueous solutions. We then combined this photoactivatable fluorophore with a SNAP (mutant of O(6)-alkylguanine DNA alkyltransferase) ligand to obtain a small-molecule-based optical highlighter for visualization of protein dynamics, using the well-established SNAP tag technology. As proof of concept, we demonstrate spatiotemporal imaging of the fusion protein of epidermal growth factor receptor (EGFR) with SNAP tag in living cells. We also demonstrate highlighting of cells of interest in live zebrafish embryos, using the fusion protein of histone 2A with SNAP tag.
Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Tomonori
T
Kobayashi
Toru
T
Komatsu
Mako
M
Kamiya
Cláudia
C
Campos
Marcos
M
González-Gaitán
Takuya
T
Terai
Kenjiro
K
Hanaoka
Tetsuo
T
Nagano
Yasuteru
Y
Urano
D000818:Animals; D001896:Boron Compounds / Q000737:chemistry*; D004625:Embryo, Nonmammalian / Q000648:ultrastructure; D066246:ErbB Receptors / Q000032:analysis* / Q000235:genetics; D005456:Fluorescent Dyes / Q000737:chemistry*; D015870:Gene Expression; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence / Q000379:methods; D009154:Mutation; D019853:O(6)-Methylguanine-DNA Methyltransferase / Q000737:chemistry* / Q000235:genetics; D010084:Oxidation-Reduction; D055668:Photochemical Processes; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000235:genetics; D013050:Spectrometry, Fluorescence / Q000379:methods; D015027:Zebrafish / Q000196:embryology
C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D005456:Fluorescent Dyes; D011993:Recombinant Fusion Proteins; D019853:O(6)-Methylguanine-DNA Methyltransferase; D066246:ErbB Receptors