Oligomerization of DsRed is required for the generation of a functional red fluorescent chromophore

FEBS Letters

Jovin, Thomas M¹  Subramaniam, Vinod¹  Sacchetti, Andrea²  Alberti, Saverio² 

[1] Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, 37070 Göttingen, Germany;Laboratory of Experimental Oncology, Department of Cell Biology and Oncology, Istituto di Ricerche Farmacologiche Mario Negri – Consorzio Mario Negri Sud, 66030 Santa Maria Imbaro (Chieti), Italy

关键词: Green fluorescent protein;    Red fluorescent protein;    Chromophore;    Protein folding;    Fluorescent energy transfer;    GFP;    green fluorescent protein;    DsRed;    red fluorescent protein;    MBP;    maltose-binding protein;   

DOI  :  10.1016/S0014-5793(02)02874-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The coral red fluorescent protein (DsRed) absorbs and emits light at much higher wavelengths than the structurally homologous green fluorescent protein, raising questions about the properties of its chromophore. We have analyzed the relationship between the aggregation state and fluorescence of native, 6-histidine-tagged, or maltose-binding protein-fused DsRed. In all cases, newly synthesized DsRed molecules were largely monomeric and devoid of covalently closed chromophores. Maturation in vitro induces the expression of red fluorescent chromophores but only in oligomeric forms of the protein, whereas monomers are essentially devoid of fluorescence. NaOH-denatured samples demonstrated a generalized breakdown of the DsRed oligomers to monomers, which refolded after neutralization into weakly green fluorescent and still monomeric species. Red fluorescent chromophores were regenerated only upon oligomerization. These findings demonstrate that ‘red’ chromophores form and are functional only as oligomers, and suggest that the smallest red fluorescent functional unit is a dimer. A comparison of alkali-, acid- and guanidinium-denatured DsRed indicates that stabilization of the DsRed chromophore by concerted steps of folding and oligomerization may play a critical role in its maturation process.

【 授权许可】

Unknown