title: Quantification of biological interactions with particle image cross-correlation spectroscopy (PICCS).
abstract: A multitude of biological processes that involve multiple interaction partners are observed by two-color microscopy. Here we describe an analysis method for the robust quantification of correlation between signals in different color channels: particle image cross-correlation spectroscopy (PICCS). The method, which exploits the superior positional accuracy obtained in single-object and single-molecule microscopy, can extract the correlation fraction and length scale. We applied PICCS to correlation measurements in living tissues. The morphogen Decapentaplegic (Dpp) was imaged in wing imaginal disks of fruit fly larvae and we quantified what fraction of early endosomes contained Dpp.
authors.affiliation: Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands.
authors.forename: Stefan
authors.initials: S
authors.lastname: Semrau
authors.forename: Laurent
authors.initials: L
authors.lastname: Holtzer
authors.forename: Marcos
authors.initials: M
authors.lastname: González-Gaitán
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmidt
mesh_terms: D000465:Algorithms; D000818:Animals; D003198:Computer Simulation; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007814:Larva / Q000378:metabolism; D008863:Microspheres; D015203:Reproducibility of Results; D013057:Spectrum Analysis / Q000379:methods*; D014921:Wings, Animal / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D005456:Fluorescent Dyes; C064196:dpp protein, Drosophila