title: A novel far-red bimolecular fluorescence complementation system that allows for efficient visualization of protein interactions under physiological conditions.
abstract: Fluorescent protein (FP) has enabled the analysis of biomolecular interactions in living cells, and bimolecular fluorescence complementation (BiFC) represents one of the newly developed imaging technologies to directly visualize protein-protein interactions in living cells. Although 10 different FPs that cover a broad range of spectra have been demonstrated to support BiFC, only Cerulean (cyan FP variant), Citrine and Venus (yellow FP variants)-based BiFC systems can be used under 37 degrees C physiological temperature. The sensitivity of two mRFP-based red BiFC systems to higher temperatures (i.e., 37 degrees C) limits their applications in most mammalian cell-based studies. Here we report that mLumin, a newly isolated far-red fluorescent protein variant of mKate with an emission maximum of 621 nm, enables BiFC analysis of protein-protein interactions at 37 degrees C in living mammalian cells. Furthermore, the combination of mLumin with Cerulean- and Venus-based BiFC systems allows for simultaneous visualization of three pairs of protein-protein interactions in the same cell. The mLumin-based BiFC system will facilitate simultaneous visualization of multiple protein-protein interactions in living cells and offer the potential to visualize protein-protein interactions in living animals.
authors: Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, PR China.
authors: Jun
authors: J
authors: Chu
authors: Zhihong
authors: Z
authors: Zhang
authors: Ying
authors: Y
authors: Zheng
authors: Jie
authors: J
authors: Yang
authors: Lingsong
authors: L
authors: Qin
authors: Jinling
authors: J
authors: Lu
authors: Zhen-Li
authors: ZL
authors: Huang
authors: Shaoqun
authors: S
authors: Zeng
authors: Qingming
authors: Q
authors: Luo
mesh_terms: D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D004926:Escherichia coli / Q000235:genetics; D005453:Fluorescence; D006367:HeLa Cells; D006801:Humans; D008164:Luminescent Proteins / Q000032:analysis* / Q000235:genetics / Q000302:isolation & purification; D008856:Microscopy, Fluorescence; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D025941:Protein Interaction Mapping / Q000379:methods*
chemical_list: D008164:Luminescent Proteins