We developed an enhanced green-emitting luciferase (ELuc) to be used as a bioluminescence imaging (BLI) probe. ELuc exhibits a light signal in mammalian cells that is over 10-fold stronger than that of the firefly luciferase (FLuc), which is the most widely used luciferase reporter gene. We showed that ELuc produces a strong light signal in primary cells and tissues and that it enables the visualization of gene expression with high temporal resolution at the single-cell level. Moreover, we successfully imaged the nucleocytoplasmic shuttling of importin α by fusing ELuc at the intracellular level. These results demonstrate that the use of ELuc allows a BLI spatiotemporal resolution far greater than that provided by FLuc.

Reporter assays that use luciferase are widely employed for monitoring cellular events associated with gene expression. In general, firefly luciferase and Renilla luciferase are used for monitoring...

We aimed to develop a far-red luminescence imaging technology for visualization of disease specific antigens on cell surfaces in a living body. First, we conjugated a far-red fluorescent indocyanine derivative to biotinylated Cypridina luciferase. This conjugate produced a bimodal spectrum that has long-wavelength bioluminescence emission in the far-red region as a result of bioluminescence resonance energy transfer. To generate a far-red luminescent probe with targeting and imaging capabilities of tumors, we then linked this conjugate to an anti-human Dlk-1 monoclonal antibody via the biotin-avidin interaction. This far-red luminescent probe enabled us to obtain high-resolution microscopic images of live, Dlk-1-expressing Huh-7 cells without an external light source, and to monitor the accumulation of this probe in tumor-bearing mice. Thus this far-red luminescent probe is a convenient analytical tool for the evaluations of monoclonal antibody localization in a living body.

Dual Reporter Assay Luciferase is widely used as a reporter due to its sensitivity and linear range, and a wide variety of luciferase-based systems are available for monitoring promoter activity in...

The luminescent marine ostracod Vargula hilgendorfii comprises distinct populations around the Japanese islands. Its mitochondrial DNA is unusual, with duplicated control regions (CRs; CR#1 and CR#2). We determined the sequences of ostracod CRs in 7 different populations. The sequences of CR#1 and CR#2 within any population were extremely similar, above 99.7%; moreover, their derived evolutionary tree indicates that the pairs of CRs have evolved in concert within each mitochondrial genome. These results suggest that an exact replication mechanism controls the concerted evolution of CRs.