Premium
Supramolecular Protein Assemblies in the Nucleus of Human Cells
Author(s) -
Bellapadrona Giuliano,
Elbaum Michael
Publication year - 2014
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201309163
Subject(s) - chemistry , fluorescence , biophysics , supramolecular chemistry , hela , nuclear pore , fusion protein , nucleus , green fluorescent protein , crystallography , microbiology and biotechnology , in vitro , biochemistry , gene , biology , cytoplasm , recombinant dna , crystal structure , physics , quantum mechanics
Genetically encoded supramolecular protein assemblies (SMPAs) are induced to form in living cells by combination of distinct self‐assembly properties. A single fusion construct contains genes encoding the heavy chain (H) of human ferritin and the citrine fluorescent protein, the latter exposing a weak dimerization interface, as well as a nuclear localization signal. Upon expression in HeLa cells, in vivo confocal fluorescence and differential interference contrast imaging revealed extended SMPA structures exclusively in the nuclei. Assemblies were typically round and took alveolar, shell‐like, or hybrid structure. Transmission electron microscopy revealed a crystalline packing. Site‐specific mutagenesis of the citrine dimerization interface clarified the mechanism of SMPA formation. The constituent proteins retained their activity in iron binding and fluorescence emission, thus suggesting a general strategy for formation of synthetic cellular bodies with specific biochemical function.