title: mPlum-IFP 1.4 fluorescent fusion protein may display Förster resonance energy transfer associated properties that can be used for near-infrared based reporter gene imaging.
abstract: Bacteriophytochrome infrared fluorescent protein (IFP) has a long emission wavelength that is appropriate for detecting pathophysiological effects via near-infrared (NIR) based imaging. However, the brightness and photostability of IFP are suboptimal, although an exogenous supply of biliverdin (BV) IXα is able to enhance these properties. In this study, we fused a far red mPlum fluorescent protein to IFP 1.4 via a linker deoxyribonucleic acid (DNA) sequence encoding eight amino acids. The brightness of mPlum-IFP 1.4 fusion protein at the IFP emission channel was comparable to that of native IFP 1.4 protein when fusion protein and IFP 1.4 were excited by 543 and 633 nm using confocal microscopy, respectively. Visualization of IFP 1.4 fluorescence by excitation of mPlum in mPlum-IFP 1.4 fusion protein is likely to be associated with Förster resonance energy transfer (FRET). The FRET phenomenon was also predicted by acceptor photobleaching using confocal microscopy. Furthermore, the expression of mPlum-IFP 1.4 fusion protein could be detected in cell culture and in xenograft tumors in the absence of BV using in vivo imaging system, although the BV was still essential for detecting native IFP 1.4. Therefore, this innovative-fluorescent fusion protein would be useful for NIR-based imaging in vitro and in vivo.
authors.affiliation: National Yang-Ming University, Department of Biomedical Imaging and Radiological Sciences, Taipei 112, Taiwan.
authors.forename: Liang-Ting
authors.initials: LT
authors.lastname: Lin
authors.affiliation: National Yang-Ming University, Department of Biomedical Imaging and Radiological Sciences, Taipei 112, Taiwan.
authors.forename: Bo-Sheng
authors.initials: BS
authors.lastname: Wang
authors.affiliation: National Yang-Ming University, Department of Biomedical Imaging and Radiological Sciences, Taipei 112, Taiwan.
authors.forename: Jyh-Cheng
authors.initials: JC
authors.lastname: Chen
authors.affiliation: Chang Gung University, Graduate Institute of Biochemical and Biomedical Engineering, Tao-Yuan 333, Taiwan.
authors.forename: Chi-Hsien
authors.initials: CH
authors.lastname: Liu
authors.affiliation: Chang Gung University, Graduate Institute of Electro-Optical Engineering, Taoyuan 33302, TaiwandChang Gung University, Health Aging Research Center, Taoyuan 33302, Taiwan.
authors.forename: Chien
authors.initials: C
authors.lastname: Chou
authors.affiliation: Tzu Chi University, Department of Life Sciences, Hualien 97004, TaiwanfInstitute of Radiation Sciences, Tzu Chi Technology College, Hualien 97004, Taiwan.
authors.forename: Shu-Jun
authors.initials: SJ
authors.lastname: Chiu
authors.affiliation: National Yang-Ming University, Department of Biomedical Imaging and Radiological Sciences, Taipei 112, Taiwan.
authors.forename: Wen-Yi
authors.initials: WY
authors.lastname: Chang
authors.affiliation: National Yang-Ming University, Department of Biomedical Imaging and Radiological Sciences, Taipei 112, TaiwangNational Yang-Ming University, Biophotonics & Molecular Imaging Research Center, Taipei 112, TaiwanhTaipei Veterans General Hospital, National PET/Cyclotron Center, Department of Nuclear Medicine, Taipei, TaiwaniNRPB/Taiwan Mouse Clinic, Molecular and Genetic Imaging Core, Taipei 112, Taiwan.
authors.forename: Ren-Shyan
authors.initials: RS
authors.lastname: Liu
authors.affiliation: National Yang-Ming University, Department of Biomedical Imaging and Radiological Sciences, Taipei 112, TaiwangNational Yang-Ming University, Biophotonics & Molecular Imaging Research Center, Taipei 112, Taiwan.
authors.forename: C
authors.initials: C
authors.lastname: Allen Chang
authors.affiliation: National Yang-Ming University, Department of Biomedical Imaging and Radiological Sciences, Taipei 112, TaiwangNational Yang-Ming University, Biophotonics & Molecular Imaging Research Center, Taipei 112, Taiwan.
authors.forename: Yi-Jang
authors.initials: YJ
authors.lastname: Lee
mesh_terms: D000818:Animals; D031541:Fluorescence Resonance Energy Transfer; D017930:Genes, Reporter / Q000235:genetics; D057809:HEK293 Cells; D006801:Humans; D008164:Luminescent Proteins / Q000032:analysis / Q000737:chemistry* / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000737:chemistry* / Q000235:genetics; D019265:Spectroscopy, Near-Infrared / Q000379:methods*
chemical_list: D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins