title: Retrieving the intracellular topology from multi-scale protein mobility mapping in living cells.
abstract: In living cells, most proteins diffuse over distances of micrometres within seconds. Protein translocation is constrained due to the cellular organization into subcompartments that impose diffusion barriers and guide enzymatic activities to their targets. Here, we introduce an approach to retrieve structural features from the scale-dependent mobility of green fluorescent protein monomer and multimers in human cells. We measure protein transport simultaneously between hundreds of positions by multi-scale fluorescence cross-correlation spectroscopy using a line-illuminating confocal microscope. From these data we derive a quantitative model of the intracellular architecture that resembles a random obstacle network for diffusing proteins. This topology partitions the cellular content and increases the dwell time of proteins in their local environment. The accessibility of obstacle surfaces depends on protein size. Our method links multi-scale mobility measurements with a quantitative description of intracellular structure that can be applied to evaluate how drug-induced perturbations affect protein transport and interactions.
authors: Deutsches Krebsforschungszentrum (DKFZ) and BioQuant, Research Group Genome Organization and Function, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
authors: Michael
authors: M
authors: Baum
authors: Deutsches Krebsforschungszentrum (DKFZ) and BioQuant, Research Group Genome Organization and Function, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
authors: Fabian
authors: F
authors: Erdel
authors: European Molecular Biology Laboratory, Cell Biology and Biophysics Unit, Meyerhofstr. 1, 69117 Heidelberg, Germany.
authors: Malte
authors: M
authors: Wachsmuth
authors: Deutsches Krebsforschungszentrum (DKFZ) and BioQuant, Research Group Genome Organization and Function, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
authors: Karsten
authors: K
authors: Rippe
mesh_terms: D002460:Cell Line; D002843:Chromatin / Q000378:metabolism; D000090266:Chromobox Protein Homolog 5; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D004058:Diffusion; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021381:Protein Transport; D011506:Proteins / Q000032:analysis* / Q000378:metabolism*; D045663:Quantum Dots; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D050795:STAT2 Transcription Factor / Q000235:genetics / Q000378:metabolism; D013050:Spectrometry, Fluorescence / Q000295:instrumentation / Q000379:methods*
chemical_list: D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D011506:Proteins; D011993:Recombinant Fusion Proteins; D050795:STAT2 Transcription Factor; D000090266:Chromobox Protein Homolog 5; D049452:Green Fluorescent Proteins