title: Reversible dimerization of Aequorea victoria fluorescent proteins increases the dynamic range of FRET-based indicators.
abstract: Fluorescent protein (FP)-based Forster resonance energy transfer (FRET) technology is useful for development of functional indicators to visualize second messenger molecules and activation of signaling components in living cells. However, the design and construction of the functional indicators require careful optimization of their structure at the atomic level. Therefore, routine procedures for constructing FRET-based indicators currently include the adjustment of the linker length between the FPs and the sensor domain and relative dipole orientation of the FP chromophore. Here we report that, in addition to these techniques, optimization of the dimerization interface of Aequorea FPs is essential to achieve the highest possible dynamic range of signal change by FRET-based indicators. We performed spectroscopic analyses of various indicators (cameleon, TN-XL, and ATeam) and their variants. We chose variants containing mutant FPs with different dimerization properties, i.e., no, weak, or enhanced dimerization of the donor or acceptor FP. Our findings revealed that the FPs that dimerized weakly yielded high-performance FRET-based indicators with the greatest dynamic range.
authors.affiliation: Research Institute for Electronic Science, Hokkaido University, Kita-20 Nishi-10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan.
authors.forename: Ippei
authors.initials: I
authors.lastname: Kotera
authors.forename: Takuya
authors.initials: T
authors.lastname: Iwasaki
authors.forename: Hiromi
authors.initials: H
authors.lastname: Imamura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Noji
authors.forename: Takeharu
authors.initials: T
authors.lastname: Nagai
mesh_terms: D005453:Fluorescence; D031541:Fluorescence Resonance Energy Transfer; D005456:Fluorescent Dyes / Q000737:chemistry*; D049452:Green Fluorescent Proteins / Q000737:chemistry* / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D009154:Mutation; D055503:Protein Multimerization
chemical_list: D005456:Fluorescent Dyes; C485192:green fluorescent protein, Aequorea victoria; D049452:Green Fluorescent Proteins